Heavy metals in intermediate He-rich hot subdwarfs: The chemical composition of HZ44 and HD127493
AAstronomy & Astrophysics manuscript no. HZ44_HD127493 c (cid:13)
ESO 2019July 19, 2019
Heavy metals in intermediate He-rich hot subdwarfs:The chemical composition of HZ 44 and HD 127493
M. Dorsch , M. Latour , and U. Heber Dr. Remeis-Sternwarte & ECAP, Astronomical Institute, University of Erlangen-Nürnberg, Sternwartstr. 7, 96049, Bamberg, Ger-many; e-mail: [email protected] Institut für Astrophysik, Georg-August-Universität, Friedrich-Hund-Platz 1, 37077, Göttingen, GermanyReceived ; accepted
ABSTRACT
Context.
Hot subluminous stars can be spectroscopically classified as subdwarf B (sdB) and O (sdO) stars. While the latter arepredominantly hydrogen deficient, the former are mostly helium deficient. The atmospheres of most sdOs are almost devoid of hydro-gen, whereas a small group of hot subdwarf stars of mixed H / He composition exists, showing extreme metal abundance anomalies.Whether such intermediate helium-rich (iHe) subdwarf stars provide an evolutionary link between the dominant classes is an openquestion.
Aims.
The presence of strong Ge, Sn, and Pb lines in the UV spectrum of HZ 44 suggests a strong enrichment of heavy elements inthis iHe-sdO star and calls for a detailed quantitative spectral analysis focusing on trans-iron elements.
Methods.
Non-LTE model atmospheres and synthetic spectra calculated with
TLUSTY / SYNSPEC are combined with high-quality opti-cal, UV and FUV spectra of HZ 44 and its hotter sibling HD 127493 to determine their atmospheric parameters and metal abundancepatterns.
Results.
By collecting atomic data from literature we succeeded to determine abundances of 29 metals in HZ 44, including the trans-iron elements Ga, Ge, As, Se, Zr, Sn, and Pb and provide upper limits for 10 other metals. This makes it the best described hotsubdwarf in terms of chemical composition. For HD 127493 the abundance of 15 metals, including Ga, Ge, and Pb and upper limitsfor another 16 metals were derived. Heavy elements turn out to be overabundant by one to four orders of magnitude with respect tothe Sun. Zr and Pb are among the most enriched elements.
Conclusions.
The C, N, and O abundance for both stars can be explained by nucleosynthesis of hydrogen burning in the CNO cyclealong with their helium enrichment. On the other hand, the heavy-element anomalies are unlikely to be caused by nucleosynthesis.Instead di ff usion processes are evoked with radiative levitation overcoming gravitational settlement of the heavy elements. Key words. stars: abundances, stars: atmospheres, stars: individual (HZ 44), stars: individual (HD 127493), stars: evolution, stars:subdwarfs
1. Introduction
Hot subdwarf stars of spectral type O and B (sdO and sdB)represent late stages of the evolution of low-mass stars. Theyare characterized by high e ff ective temperatures, ranging from T e ff =
20 000 K to more than 45 000 K while their surface grav-ities are typically between log g = . n (He) / n (H) = − ∼ M (cid:12) ; Dorman et al. 1993; Han et al. 2002; Fontaineet al. 2012). Unlike normal horizontal branch objects, the sdBstars, due to their lack of H-shell burning, evolve directly to thewhite dwarf (WD) cooling sequence without an excursion to theasymptotic giant branch (AGB) (Dorman et al. 1993).The formation and evolutionary history of the sdO stars is not understood very well. Because most sdO stars are hotter andsomewhat more luminous than the sdB stars, they can not beassociated to the EHB. Whether their evolution is linked to theEHB or not remains an open question. It has been suggested thatthe He-deficient sdO stars are the descendants of the sdB stars,because they share the peculiar chemical composition (Heber2016). However, the majority of sdO stars have atmospheresdominated by helium with hydrogen being a trace element only.The formation of these He-sdO stars is unlikely to be linked tothe EHB and two rivaling scenarios have been invoked to explainthe hydrogen deficiency, either via internal mixing (Lanz et al.2004; Miller Bertolami et al. 2008) or via a merger of two heliumwhite dwarfs (Zhang & Je ff ery 2012). A very small number ofhot subluminous stars have atmospheres of mixed H / He compo-sition. Because their metal content is very di ff erent from that ofthe extremely He-rich subdwarfs, Naslim et al. (2013) suggestedto distinguish intermediate H / He composition subdwarfs (iHe-sds) with n (He) / n (H) < Article number, page 1 of 48 a r X i v : . [ a s t r o - ph . S R ] J u l & A proofs: manuscript no. HZ44_HD127493 T eff / K321012 l o g N H e / N H eHe sdi He sdH-rich sdHE2359-2844HE1256-2738LSIV-14°116[CW83]0825+15HZ44HD127493 Fig. 1: Distribution of helium abundance versus T e ff for thesubdwarf population from the SPY sample (Lisker et al. 2005;Stroeer et al. 2007; Hirsch 2009). The dashed lines mark therange of iHe subdwarfs. The two heavy-metal subdwarfs fromSPY (Naslim et al. 2013) and the prototypical heavy-metal subd-warfs LS IV − ◦
116 (Naslim et al. 2011) and [CW83] 0825 + ff ery et al. 2017) are marked by blue triangles, HD 127493and HZ 44 in red. Open symbols represent C-poor, N-rich stars,filled symbols C-rich stars.2009). The latter appear as a transition stage between the coolerH-rich sdB stars and the hotter eHe subdwarf stars (see Fig. 1).As to the carbon and nitrogen abundances a dichotomy exists,both for the eHe and the iHe sds. Stroeer et al. (2007) classifiedthe line spectra of helium-rich hot subdwarfs in three classes:N-, C-, and C&N-strong. Hirsch (2009) showed that, indeed, theN strong-lined stars are enriched in nitrogen with respect to theSun, as are the C strong-lined enriched in carbon and the C&Nstrong-lined in both elements. This dichotomy is most obviousfor the eHe hot subdwarf stars, the N-strong ones being mostlycooler than the C- or C&N- strong ones. For the iHe hot subd-warfs such a separation is less pronounced (see Fig. 1).Naslim et al. (2011) have discovered trans-iron elements, inparticular zirconium and lead, to be strongly overabundant inthe iHe-sdB LS IV − ◦ ff ective temperature between 35 000 K and 40 000 K, have beenfound to be extremely enriched in heavy elements (Naslim et al.2013; Je ff ery et al. 2017). The origin of the extreme enrichmentobserved in iHe hot subdwarfs is not yet understood. Radiativelydriven di ff usion has been proposed, but is poorly constrainedwith only four stars ([CW83] 0825 +
15, LS IV − ◦ a Star Instrument Range (Å) R S / NHD 127493 IUE SWP 1150 − − b − − − − − − b Notes. ( a ) The signal-to-noise ratio is the average over the spectrum. ( b ) The resolution for long-slit spectrographs is given instead as ∆ λ . growth analysis Peterson (1970) derived metal abundances forthe first time, but we know of no contemporary study. HZ 44 isnow a spectrophotometric standard star (Massey et al. 1988; Oke1990; Landolt & Uomoto 2007a), used for the calibration of theHST (Bohlin et al. 1990; Bohlin 1996; Bohlin et al. 2001), aswell as that of Gaia (Marinoni et al. 2016), and therefore hasfrequently been observed. High resolution spectra are availablefrom the far-UV to the red in the FUSE, IUE, and HIRES@Keckdata archives.HD 127493 has been used as secondary spectrophotometric stan-dard star (Spencer Jones 1985; Kilkenny et al. 1998; Bessell1999). Therefore, very accurate photometry is available but spec-troscopic observations are not as extensive as for HZ 44. Startingwith the curve of growth analyses of Peterson (1970) and Tom-ley (1970) abundances of C, N, O, Ne, Mg, and Si were derived.The first NLTE model atmospheres were calculated by Kudritzki(1976), who revised the atmospheric parameters. Abundances ofcarbon (Gruschinske et al. 1980) and C, N, O and Si (Simonet al. 1980) were derived from equivalent widths of ultravioletlines. A NLTE analyis of optical spectra allowed Bauer & Hus-feld (1995) to determine the abundances of C, N, O, Ne, Mg, Al,and Si. The most recent NLTE analysis by Hirsch (2009) revisedthe atmospheric parameters and determined C and N abundancesfrom optical spectra. For completeness we give a comparisonof our results with those of previous analyses in the Appendix.Hence, our knowledge of the chemical composition of both starsis rather limited. The paper is organized as follows. In Sect. 2 we provide a de-scription of the available spectra followed by a presentationof the atmospheric parameters that we derived for our stars inSect. 3. The spectroscopic masses obtained from the spectralenergy distributions and the
Gaia parallaxes are presented inSect. 4. The atomic data used for our abundance analysis are dis-cussed in Sect. 5. In Sect. 6 we provide details on the abundanceanalysis of all considered metallic elements. The abundance pat-terns for HZ 44 and HD 127493 are discussed in Sect. 7 and weconclude in Sect. 8.
2. Spectroscopic observations
For both stars excellent archival data are available in both theoptical and UV ranges. An overview of the spectra we collected The abundance analysis performed in this paper is based on, revises,and extends results for HD 127493 from Dorsch et al. (2018).Article number, page 2 of 48. Dorsch et al.: The chemical composition of HZ 44 and HD 127493 and used is given in Table 1, with additional details on the indi-vidual observations listed in Table A.1.We used optical FEROS spectra to determine the atmosphericparameters of HD 127493 and measure photospheric metal abun-dances. FEROS is an echelle spectrograph mounted on theMPG / ESO-2.20m telescope operated by the European SouthernObservatory (ESO) in La Silla. It features a high resolving powerof R ≈ ∼ ∼ i , He ii , and metal lines. The three available spectraof HD 127493 were co-added to achieve a high signal-to-noiseratio (S / N) of (cid:38)
100 in the 4000 – 6000 Å range. Nevertheless,the S / N decreases drastically toward both ends of the spectralrange and especially below 3800 Å.Both stars have been observed with the International Ultravi-olet Explorer (IUE) satellite with the short-wavelength prime(SWP) camera. We retrieved three archival INES spectra forHD 127493 and two for HZ 44. For each star we co-added theindividual spectra to increase the S / N. They continuously coverthe 1150 – 1980 Å range with a resolution of R ≈ / N drops sharply atboth ends of the spectra. Fewer lines are observed in this wave-length range but the IUE LWR spectrum of HD 127493 has nev-ertheless been useful for the abundance analysis.HD 127493 has also been observed with the Goddard High-Resolution Spectrograph (GHRS) mounted on the Hubble SpaceTelescope (HST). These spectra are publicly available in theMAST archive and cover the 1225 – 1745 Å range with a res-olution of ∆ λ ≈ .
07 Å. The final spectrum is a combina-tion of ten observations spanning 35 Å each and lacks coveragein the following regions: 1450.5 – 1532.5 Å, 1567.7 – 1623.2 Å,and 1658.1 – 1713.0 Å. Since the wavelength calibration was notperfect, we cross-correlated the individual spectra to match thesynthetic spectrum of HD 127493. In addition, they were shiftedto match the flux level of the IUE spectra.HZ 44 has been observed with the Far Ultraviolet SpectroscopicExplorer (FUSE) satellite over the spectral range between 905 Åand 1188 Å. We retrieved three calibrated observations fromMAST, two taken through the LWRS (30” × × / N spectrum taken with the In-termediate dispersion Spectrograph and Imaging System (ISIS)mounted at the Cassegrain focus of the 4.2m William HerschelTelescope on La Palma. The spectrum covers the 3700 − α , as well as He i and ii lines.The spectra of HZ 44 taken with the HIRES echelle spectrographmounted on the Keck I telescope on Mauna Kea were most valu-able for our abundance analysis. A total of 68 extracted HIRES IUE Newly-Extracted Spectra, http://sdc.cab.inta-csic.es/ines/index2.html Mikulski Archive for Space Telescopes, https://archive.stsci.edu/index.html spectra of HZ 44 from several programs covering various wave-length ranges are available in the Keck Observatory Archive(KOA ). We co-added the spectra of four high S / N HIRES ob-servations to produce the spectrum used for our abundance anal-ysis. To access the ranges between 3022 Å and 3128 Å and above5990 Å we considered two additional HIRES spectra that wereused specifically for these regions. Additional spectra were alsoretrieved from the archive and used to measure radial velocities.Unfortunately, the normalization of HIRES spectra is di ffi cultsince the spectral orders are narrower than many broad Balmeror helium lines. This is not a problem for sharp metal lines, butrenders the spectra next to useless for the determination of atmo-spheric parameters of HZ 44.
3. Atmospheric parameters and radial velocities
In order to analyze the spectra of our stars we computed non-LTEmodel atmospheres using the
TLUSTY and
SYNSPEC codes devel-oped by Hubeny (1988) and Lanz & Hubeny (2003). A detaileddescription of
TLUSTY / SYNSPEC has recently been published inHubeny & Lanz (2017a,b,c).We derived atmospheric parameters for both stars using opti-cal spectra (besides HIRES) and a newly constructed model at-mosphere grid that includes e ff ective temperatures from T e ff =
35 000 K to 48 000 K in steps of 1000 K and surface gravitiesfrom log g = n He / n H = − . + . i - ii lines for both stars are re-ported in Table 2. The atmospheric parameters for HD 127493derived by Hirsch (2009) are also listed. They were obtainedwith the same FEROS spectrum but di ff erent model atmospheresand are fully consistent with our results. As shown in Fig. 1 theatmospheric parameters of both stars fit very well the trend ofhelium abundance to increase with increasing e ff ective tempera-tures. We found no indication of rotation or microturbulence ineither star; some optical metal lines are in fact sharper in the ob-servations than in the models.Radial velocities of HZ 44 in 27 HIRES spectra taken between1995 and 2016 were measured by Schork (2018) and are listedin Table A.2. From these values an average radial velocity of v rad = − . ± . − was derived. The measurementsshow that the radial velocity of HZ 44 does not vary on a scaleof a few km s − . Within the radial velocity uncertainties, nei-ther a short- nor a long-period companion is detected. Our ra-dial velocity measurement for HD 127493 is consistent with thevalue derived by Hirsch (2009) using the same FEROS spectrum( − ± − ). Keck Observatory Archive, https://koa.ipac.caltech.edu/cgi-bin/KOA/nph-KOAlogin
Article number, page 3 of 48 & A proofs: manuscript no. HZ44_HD127493
60 40 20 0 20 40 600.50.60.70.80.91.0
H /HeII
60 40 20 0 20 40 600.50.60.70.80.91.0
HeII
40 20 0 20 400.50.60.70.80.91.0
H /HeII
40 20 0 20 400.50.60.70.80.91.0
HeII
40 30 20 10 0 10 20 300.50.60.70.80.91.0
H /HeII
40 20 0 20 400.50.60.70.80.91.0
HeII
40 30 20 10 0 10 20 300.50.60.70.80.91.0
H /HeII + HeI
30 20 10 0 10 200.50.60.70.80.91.0
HeII
20 15 10 5 0 5 10 150.50.60.70.80.91.0
HeI
15 10 5 0 5 10 150.50.60.70.80.91.0
HeI HeI
20 10 0 10 200.50.60.70.80.91.0
HeI
20 15 10 5 0 5 10 150.50.60.70.80.91.0
HeI + NIII
30 20 10 0 10 20 300.50.60.70.80.91.0
HeI
30 20 10 0 10 200.50.60.70.80.91.0
HeI HeI HeI HeI ( Å ) N o r m a li z e d F l u x Fig. 2: Best fit (red) to the Balmer and helium lines selected in the normalized FEROS spectrum of HD 127493 (black).
Article number, page 4 of 48. Dorsch et al.: The chemical composition of HZ 44 and HD 127493
60 40 20 0 20 40 60 80 1000.60.70.80.91.0
H /HeII + HeI
40 20 0 20 40 600.60.70.80.91.0
H /HeII + HeI
60 40 20 0 20 40 60 800.60.70.80.91.0
H /HeII + HeI
40 20 0 20 40 60 80 1000.60.70.80.91.0
HeI + HeII
40 30 20 10 0 10 20 30 400.60.70.80.91.0
HeII + HeI
40 20 0 20 40 60 800.60.70.80.91.0
H /HeII + HeI
20 15 10 5 0 5 10 150.60.70.80.91.0
HeI
10 5 0 5 10 150.60.70.80.91.0
HeI ( Å ) N o r m a li z e d F l u x Fig. 3: Best fit (red) to the Balmer and helium lines selected in the flux-calibrated ISIS spectrum of HZ 44 (black).Table 2: Parameters derived from optical spectroscopy.Name T e ff log g log n He / n H v rot sin i Spectrum Ref[K] [cgs] [km s − ]HZ 44 39100 ±
600 5 . ± .
10 0 . ± . < ±
180 5 . ± .
04 0 . ± . <
10 FEROS 142480 ±
250 5 . ± .
05 0 . ± . <
10 FEROS 2
Notes.
References: ( ) this work ( ) Hirsch (2009) . The uncertainties stated were determined using di ff erent methods. Uncertainties on our resultsare determined using the bootstrapping method. Please to refer Hirsch (2009) for an explanation of their uncertainties.Article number, page 5 of 48 & A proofs: manuscript no. HZ44_HD127493 -0.1 0.050-0.05 U − BB − VV − RR − IV − Im b − yH β f λ ( − er g c m − s − Å ) λ (Å) m x , m o d e l − m x ( m ag ) m x , model − m x (mag) V G RP G BP G boxboxbox W W Y K J H y K J H -0.05 V − I V − R U − BB − VU − B B − Vm c b − yH β U − B B − V f λ ( − er g c m − s − Å ) λ (Å) m x , m o d e l − m x ( m ag ) m x , model − m x (mag) VV G RP G BP G boxboxbox W W y V K J H Fig. 4: Comparison of synthetic spectra with photometric data for HZ 44 (top) and HD 127493 (bottom). The three black data pointslabeled “box” are binned fluxes from a low-dispersion IUE spectrum. Filter-averaged fluxes are shown as colored data points thatwere converted from observed magnitudes (the dashed horizontal lines indicate the respective filter widths), while the gray solid linerepresents a synthetic spectrum using the atmospheric parameters given in Table 2. The residual panels at the bottom and right handside show the di ff erences between synthetic and observed magnitudes / colors. The following color codes are used to identify thephotometric systems: Johnson-Cousins (blue), Strömgren (green), Gaia (cyan), UKIDSS (rose), 2MASS (red), WISE (magenta).
Article number, page 6 of 48. Dorsch et al.: The chemical composition of HZ 44 and HD 127493
Table 3: Parallax and parameters derived from the SED fitting.Results HZ 44 HD 127493 (cid:36) (mas) 2 . ± .
08 5 . ± . d (pc) 403 ±
13 172 ± θ (10 − rad) 2 . ± .
011 4 . ± . E B − V . ± .
004 0 . ± . R / R (cid:12) . ± .
007 0 . ± . M / M (cid:12) . ± .
14 0 . ± . L / L (cid:12) ± ±
4. Stellar masses, radii, and luminosities
With the release of
Gaia
DR2, high accuracy parallax ( (cid:36) ) andtherefore distance measurements have become available for alarge sample of hot subdwarfs. This allows us to derive moreprecise spectroscopic masses for these stars. We collected pho-tometric measurements from several surveys and converted theminto fluxes (see Tables A.3 and A.4). In addition, we use low-resolution, large-aperture IUE spectra that were averaged inthree regions (1300–1800 Å, 2000–2500 Å, 2500–3000 Å) as“box filters” to cover the UV range. Our photometric fitting pro-cedure is described in detail in Heber et al. (2018). The χ fittingprocedure scales our final synthetic spectra to match the pho-tometric data and has the solid angle θ = R / D and the colorexcess E B − V as free parameters. Reddening is modeled with R V = . ff use ISM) and the corresponding mean extinction law fromFitzpatrick (1999). The resulting solid angle can be combinedwith the Gaia parallax distance to obtain the stellar radius, fromwhich the stellar mass can be computed using the surface gravityderived from spectroscopy. The SED-fits are shown in Fig. 4 andthe derived parameters in Table 3. Considering the non-detectionof radial velocity variations and the evident lack of an IR ex-cess, we can state that there is no indication of binarity in HZ 44.The SED of HD 127493 also shows no IR excess that would hintat a companion. The masses determined from the SED-fits areconsistent with the canonical subdwarf mass, 0.47 M (cid:12) (Fontaineet al. 2012, and references therein).
5. Atomic data
While atomic data and line lists for elements lighter than theiron-group are readily accessible via, for example, the Kuruczcompilations and the NIST database, data for trans-iron ele-ments are much more scarce. Since these elements are of specialinterest for the analysis of our two stars we invested particular ef-fort into searching the literature and collecting data (energy lev-els, line positions, and oscillator strengths) for many trans-ironelements. We list in Table 4 the ions that we took into consid-eration as well as the references for their atomic data. We alsoinclude in this table, for each ion, the number of lines visible(with a predicted equivalent width greater than 5 mÅ) in the fi-nal model spectrum of HZ 44. The basis of our line list is themost recent line list published by Kurucz (2018) and available National Institute of Standards and Technology, https://physics.nist.gov/PhysRefData/ASD/lines_form.html online . The list was further extended with data listed in ALL,the Atomic Line List (v2.05b21) . In the context of their ongoing“Stellar Laboratories” series, Rauch et al. (2015) have publisheda large collection of atomic data for elements with Z ≥
30 onthe TOSS website. While this collection was made for the anal-ysis of hot white dwarfs with T e ff >
60 000 K, it also includesatomic data for ions of stages iv - v that are observed in the sdOsdiscussed here. Thus, additional lines were added from TOSSand other theoretical works listed in Table 4. Finally the list wasmerged with the collection of lines from low-lying energy lev-els by Morton (2000) but preferring more recent data if available.Hyper-fine structure and isotopic line splitting are not consideredbecause of the lack of atomic data. For subordinate lines the ef-fect is expected to be small, but may be significant for resonancelines (e. g. Mashonkina et al. 2003) such as the Pb iv
6. Metal abundance analysis
Model atmospheres were calculated for each star using their at-mospheric parameters as listed in Table 2. All ions for whichmodel atoms are available are included in non-LTE (see Table 5),while the remaining elements are treated with the LTE approxi-mation. The next higher ionization stage of each metal listed inTable 5 is considered as a one-level ion. More information onthe model atoms we use can be found on the
TLUSTY web site and in Lanz & Hubeny (2003, 2007). The Mg iii - v and Ar iv - v model atoms are described in Latour et al. (2013). The Ca iii - iv model atoms were constructed in a similar manner (P. Chayer,priv. comm.) while the Ca ii model atom is described in AllendePrieto et al. (2003). To compute the partition functions of heavyelements (Z >
30) in ionization stages iv – vi we added atomic datafrom NIST to SYNSPEC , as in Chayer et al. (2006). As a start-ing point, abundances in the
TLUSTY model were set to valuesestimated by eye for each element. Based on this preliminarymodel, a series of synthetic spectra with a range of abundancesfor each element were created with
SYNSPEC . The abundance ofthe elements were determined one-by-one using the downhill-simplex fitting program
SPAS developed by Hirsch (2009). Thismethod works well for isolated lines but is not reliable for heav-ily blended lines, in particular in the UV region. The abundancefor these elements was estimated by manually comparing mod-els with the observation. Even with this method, the placementof the continuum (especially in the FUSE range) remains an im-portant source of uncertainty. As noted by Pereira et al. (2006),the true continuum in the FUSE spectral region may be wellabove the highest observed fluxes. This complicates the contin-uum placement since some opacity (photospheric and interstel-lar) is still missing in our final synthetic spectra. Thus for someelements we could only derive upper limits. This includes ele-ments having low abundances but also elements that show linesin the FUSE range only, where the aforementioned problems aremost severe. For some elements in HD 127493 no abundances, Kurucz / Linelists, http://kurucz.harvard.edu/linelists/gfnew/gfall08oct17.dat Atomic Line List (v2.05b21), Tübingen Oscillator Strengths Service, http://dc.g-vo.org/TOSS http://tlusty.oca.eu/Tlusty2002/tlusty-frames-data.html Article number, page 7 of 48 & A proofs: manuscript no. HZ44_HD127493
Table 4: Data for elements not included in the Kurucz line-list ( gfall08oct17.dat ).Ion N UV N VIS
ReferenceGa iii iv − v − iii − iv v − iii − − iv − v − iv ∗ − v ∗ − iv ∗
42 6 3Kr v ∗ − − iv ∗
109 1 3 Ion N UV N VIS
ReferenceSr v ∗ − iii ∗ iv
11 8 3Zr v − − iv ∗ − v ∗ − vi ∗ − iii ∗ − iii − − iv −
4, 12Sb iii ∗ − − iv ∗ − v ∗ − iii ∗ − −
14 Ion N UV N VIS
ReferenceTe v ∗ − vi ∗ − iv ∗ − v ∗ − v ∗ − iii ∗ − − iii −
7, 1(24)Pb iv
17 9 11, 5, 8, 1(24)Pb v − iii ∗ − − iv ∗ − − v ∗ − iv ∗ − Notes.
The number of lines with predicted equivalent width greater than 5 mÅ in the final model of HZ 44 (upper limits marked with ∗ ) and inspectral ranges where observations are available for HZ 44 are listed (UV: 916 − − or upper limits, could be derived (Cl, K, As, Se, Sb, Xe, Bi). Thisis due to insu ffi cient spectral coverage: the elements in questionhave their strongest spectral lines in ranges where no data areavailable for that star (FUSE, UVA).A summary of the photospheric abundances derived for HZ 44and HD 127493 are presented at the end of this section in Fig. 12and in Table A.5. In addition, we include in Sect. A.3 a com-parison between the final synthetic spectrum and the observedspectrum in all wavelength ranges for both stars. We note thatfor some elements, namely Ne, Ar, Cl, Sn, Tl, Pb, and Th,the uncertainty on their solar photospheric abundance (Asplundet al. 2009) contributes significantly to the total uncertaintywhen computing the ratio with solar abundances. The uncer-tainty stated on upper limits and by-eye abundances is definedas follows: at the upper bound the lines are judged to be clearlytoo strong, while they can not be distinguished from noise at thelower bound.In the following subsections, we present in detail the result of ourabundance analysis for each element. Light elements (C, N, O)are discussed in Sect. 6.1, intermediate elements (F, Ne, Na, Mg,Al, Si, P, S, Cl, Ar, K, Ca, Ti) in Sect. 6.2, iron-group elementstreated in non-LTE (Fe, Ni) in Sect. 6.3, iron-group elementstreated in LTE (V, Cr, Mn, Co, Cu, Zn) in Sect. 6.4, detectedtrans-iron elements (Ga, Ge, As, Se, Zr, Sn, Pb) in Sect. 6.5,and trans-iron elements with upper limits (Kr, Sr, Y, Mo, Sb, Te,Xe, Th) in Sect. 6.6. Finally, Sect. 6.7 addresses the elementsfor which we could not even assess an upper limit due to theweakness of their predicted lines (Sc, In, Ba, Tl, Bi). We thendiscuss the chemical portrait obtained for both stars in Sect. 6.8.In the rest of the paper we give our abundances as log n X / n H anduse the shorter notation log X / H. Here, n X is the dimensionlessnumber fraction. To put the abundances in perspective, we addi-tionally state the corresponding number fraction relative to solarvalues n X / n X , (cid:12) . The carbon abundance in HZ 44 was measured using nine op-tical C iii lines. The abundance derived this way, log C / H = − . ± .
13 (8 . × − times solar), is consistent with the strongC iii and C iv lines observed in the UV region. Carbon lines areweaker in the optical spectrum of HD 127493. We use the reso-nance doublet C iv λλ iii sextuplet linesat 1175 Å to derive an abundance of log C / H = − . ± . . × − times solar).The nitrogen abundances measured in HZ 44 from di ff erentionization stages / lines in the optical region are not very con-sistent. Most N iii lines are well reproduced; some are toostrong (e. g. N iii λλ iii iv linein the optical spectrum of HZ 44 (N iv / H = − . ± .
21 (29 times solar) for HZ 44. However, many strongN ii lines are too broad and shallow in the model, even assum-ing a rotation velocity and microturbulence of 0 km s − and weretherefore excluded from the fit (e. g. N ii λλ ii lines are even more pronounced; they appear in emission inthe model and were excluded from the fit. In addition to opticalN iii - iv lines we used UV lines to constrain the abundance, in-cluding the N v λλ . , . iv iii lines. All ionization stages givea consistent abundance of log N / H = − . ± .
17 (26 times so-lar).The abundance of oxygen in HZ 44 was measured using opticalO ii and O iii lines. Although these lines are weak compared tolines from other elements, they could be used to find an abun-dance of log O / H = − . ± .
13 (12 × − times solar). The Article number, page 8 of 48. Dorsch et al.: The chemical composition of HZ 44 and HD 127493
Table 5: Model atoms used for the final model of HZ 44 withtheir number of explicit levels (L) and superlevels (SL).Ion L SLH i − He i − He ii − C ii
34 5C iii
34 12C iv
35 2N ii
32 10N iii
40 9N iv
34 14N v
21 4O ii
36 12O iii
28 13O iv
31 8O v
34 6O vi
15 5Ne ii
23 9Ne iii
22 12Ne iv
10 2Mg ii
21 4Mg iii
37 3Mg iv
29 5Mg v
18 2Al ii
20 9Al iii
19 4 Ion L SLSi ii
36 4Si iii
31 15Si iv
19 4P iv − P v
13 4S ii
23 10S iii
29 12S iv
33 5S v
20 5S vi
13 3Ar ii
42 12Ar iii
27 17Ar iv − Ar v − Ca ii − Ca iii
15 4Ca iv
17 4Fe iii − iv − v − iii − iv − v − iii iv / SWP spectrum) supportthis value. O iv λλ / H ≤ − . × − times solar) and note that the actualabundance is likely not significantly lower. For HZ 44, all elements from fluorine to titanium were analyzed.Due to the lack of UVA and FUSE spectra, P, Cl, Ar, K, and Ticould not be studied in HD 127493.No fluorine lines are observed in HZ 44 which allows us toprovide an upper limit of log F / H ≤ − . ± . ii λλ ii lines are strong enough inHD 127493 set a meaningful limit on the abundance.The neon abundance measurement for HZ 44 is based on sev-eral strong Ne ii lines, which are weaker in HD 127493 due toits higher temperature. Most of them lie between 3300 Å and3800 Å though some strong Ne ii lines exist at longer wave-lengths. Fitting all accessible Ne lines results in log Ne / H = − . ± .
11 (3 . / H = − . ± .
18 (3 . iii lines arereasonably well reproduced with the abundance stated above. Sodium lines are weak, but clearly visible in HZ 44, most no-tably Na ii λλ / H = − . ± .
06 (10 times solar) for HZ 44. Na ii λλ / H ≤ − . ± . magnesium lines are by far the Mg ii triplet at 4481 Å. All other optical lines are too weak to be ob-served in either star. We derive log Mg / H = − . ± . / H = − . ± . ii aluminum abundance in HZ 44 to be log Al / H = − . ± .
11 (2.4 times solar) based on eleven optical Al iii lines.This abundance is consistent with strong Al iii lines observedin the UV range, including the Al iii λλ / H = − . ± .
10 (2.2 times solar), is derived from Al iii λλ silicon lines in their optical and UVspectra. The abundance measurement for HZ 44 is based onten optical Si iii and nine optical Si iv lines. The derived abun-dance of log Si / H = − . ± .
11 (2.0 times solar) is con-sistent with the resonance lines Si iv λλ iv λλ iii iv λλ / H = − . ± .
14 (3.2 times solar).The strongest observed phosphorus lines lie in the FUSE spec-tral range which is only accessible for HZ 44. This includesthe P v λλ iv iv lines, e. g. P iv / UVA range, there are only three observable lines:P iv λλ iv / H = − . ± .
25 (4.1 times solar)for HZ 44. There are only two unambiguously identified P linesin HD 127493: P iv iv / H = − . ± . sulfur iii - iv lines at optical wavelengths,we observed strong S iii - vi lines in the UV spectrum of HZ 44(e. g. S iv λλ / H = − . ± .
37 (4.9 timessolar) based on optical S iii - iv lines is consistent with the UVlines. Several optical S iii lines are too weak and broad inthe model (e. g. S iii λλ / H = − . ± .
35 (2.0 times solar) from UV lines,consistent with optical lines such as S iv λλ Chlorine shows strong lines from low-lying levels in theFUSE spectral region (Cl iv λλ ff ects. In addition,the usual problems with lines in the FUSE spectra apply: theysu ff er from unidentified blends, both of stellar and interstellarorigin. Nevertheless, the abundance of log Cl / H = − . ± . Article number, page 9 of 48 & A proofs: manuscript no. HZ44_HD127493 despite the large uncertainty.
Argon shows many strong lines in the UVA spectrum of HZ 44.We determine an abundance of log Ar / H = − . ± .
11 (31times solar) for HZ 44 based on optical / UVA lines. Some strongAr iii lines (e. g. Ar iii λλ ii lines – they are very narrow in the ob-servation and too broad in the model. Except for a very weakAr iii / H ≤ − . ± . iv λλ iv v potassium lines in the UV spectrum ofHZ 44, but some optical lines were clearly identified. Howeverseveral lines appear to lie at shorter wavelengths than listed inthe Kurucz line list. Since the di ff erence correlates with theirLS-coupling terms, it seemed reasonable to shift them in orderto match their observed position. Their wavelengths and config-urations are listed in Table 6. Other K lines are clearly identifiedat wavelengths very close to their listed value (K iii λλ P lowerterm had to be shifted by approximately − . P lower terms. All identi-fied lines are reproduced reasonably well with an abundance oflog K / H = − . ± .
16 (55 times solar), when shifted to theobserved position.Table 6: K iii lines with deviation between predicted and ob-served wavelengths. λ Kurucz (Å) λ obs (Å) ∆ λ (Å) Configuration3253.973 3253.563 − .
41 4s P / − D ◦ / − .
10 4s P / − P ◦ / − .
25 4s P / − D ◦ / ∗ − . − .
07 4s P / − P ◦ / ∗ − . − .
08 4s P / − P ◦ / − .
62 4s P / − P ◦ / − .
05 4s P / − P ◦ / − .
04 4s P / − P ◦ / Notes.
The configurations are taken from NIST. The term superscript ◦ indicates odd parity. The superscript ∗ marks alternative identifications. While there are no usable calcium lines in the optical spectrumof HD 127493, HZ 44 shows some strong Ca ii and Ca iii lines.The optical resonance lines Ca ii λλ iii lines were excluded fromthe fit (e. g. Ca iii λλ ii and Ca iii in non-LTE. We measure log Ca / H = − . ± .
24 (28 times solar) forHZ 44 and derive an upper limit of log Ca / H ≤ − . ± . iii iv λλ − . − . − . − . . . . . . Wavelength (˚ A ) N o r m a li z e d F l u x + O ff s e t . λ λ λ λ λ λ K III T i III K III K III K III N e II T i III K III A r III N III K III P I V Fig. 5: The strongest K iii lines in the observed spectrum ofHZ 44. The model using the Kurucz wavelengths is shown inred, while a model with shifted lines is shown in blue. Alterna-tive line shifts are shown in violet (marked with ∗ in Table 6). Allmodels have a potassium abundance of log K / H = − titanium iii - iv lines lie in the UVA spectral regionalthough some lines exist at longer wavelengths. We measure astrong enrichment in HZ 44 with log Ti / H = − . ± .
22 (150times solar). This abundance is consistent between strong opti-cal and ultraviolet lines (e. g. Ti iv λλ iii iv λλ iv λλ / H ≤ − . ± .
25 (94 times solar)for HD 127493 based on optical lines. However, Ti iii - iv lines inthe IUE range would favor higher abundances. We determine iron abundances by fitting the IUE spectrum ofHZ 44 and the GHRS spectrum of HD 127493 in ranges thatspan 10 to 20 Å, from 1300 Å onward (at shorter wavelengths,
Article number, page 10 of 48. Dorsch et al.: The chemical composition of HZ 44 and HD 127493
Wavelength (Å) N u m b e r ( E W > m Å ) ZnCuNiCoFeMnCr
Fig. 6: Histogram of iron-peak lines with estimated equivalentwidths larger than 5 mÅ in the final model of HZ44. Bins areevery 50 Å. Elements are listed in the legend in the same orderas they appear in the histogram.the amount of unidentified opacity increases). Since Fe and Niwere fitted separately, blends are not treated exactly which maylead to overestimated abundances. However, since abundances inthe initial model were already close to the best-fit abundances,this e ff ect is partly compensated. Missing opacity from othersources may also introduce a bias toward higher abundances butsince the observed spectrum is well-reproduced in the consid-ered ranges, we are confident that the derived abundances arereliable within their respective uncertainties. The average of theabundances over all ranges yields log Fe / H = − . ± .
25 (1.5times solar) for HZ 44 and log Fe / H = − . ± .
13 (10 timessolar) for HD 127493.The same procedure was applied for nickel , resulting inlog Ni / H = − . ± .
15 (26 times solar) for HZ 44 andlog Ni / H = − . ± .
13 (31 times solar) for HD 127493.
The UV spectral range is dominated by lines from iron-peak el-ements. Although most lines are from iron and nickel, opacitycontributions from other iron-peak elements are also significant.Figure 6 shows the number of lines from iron-peak elements withestimated equivalent width larger than 5 mÅ in the final modelfor HZ 44. While many of these lines are observed in FUSE andIUE spectra, the opacity peak below 900Å is outside of our ob-served spectral range.Our models include only Fe and Ni in non-LTE.Many vanadium lines in the IUE spectrum of HZ 44 wouldfit well with abundances of up to log V / H = − . iv λλ v / H ≤− . ± .
4, e. g. V iv λλ / H ≤ − . ± .
4, e. g. V iv λλ iii / H ≤ − . ± . iv λλ / H ≤− . ± . Chromium shows many strong lines in the ultraviolet spectrumof both stars, e. g. Cr iv λλ / H = − . ± . / H = − . ± . manganese abundance in HZ 44 from FUSEand IUE to be log Mn / H = − . ± . iii λλ iv λλ / H ≤ − . ± . iv λλ Cobalt lines in the FUSE spectrum of HZ 44 (e. g. Co iii λλ / H ≤− . ± .
4. Many Co lines in the IUE region, e. g.Co iv λλ iv λλ / H = − . ± . iv λλ / H = − .
1, whileCo iv λλ / H ≤ − .
3. We therefore adopt an abundanceof log Co / H = − . ± . ff ects.Many strong copper lines lie in the FUV spectral region.Cu iv λλ ff ected by unidentified blends or lie in a re-gion where the continuum placement is not well constrained.Cu lines are weaker in the IUE spectrum, with a few no-table exceptions: Cu iii λλ / H = − . ± . v linessuch as Cu v λλ / H ≤ − . ± . zinc abundances in HZ 44 and HD 127493 are based onstrong Zn iii - iv lines that lie mostly in the IUE spectral range.Zn iv is the dominant ion in HD 127493 while HZ 44 showsabout the same amount of Zn iii and Zn iv lines. We derivelog Zn / H = − . ± . / H = − . ± . Article number, page 11 of 48 & A proofs: manuscript no. HZ44_HD127493 − . − . . . . Wavelength (˚ A ) N o r m a li z e d F l u x + O ff s e t . λ λ N i V F e I V N i V N i V G e I V F e V I N i V S i I V N i V N i V N i V N i V N i V N i V P b I V P b I V P b I V P b I V P b I V N i V N i I V N III
Fig. 7: Ge iv and Pb iv lines in the GHRS spectrum ofHD 127493. In blue: a model with log Ge / H = − .
0, log Pb / H = − .
7. In red: the same model without Pb and Ge.
We were able to measure the abundance of Ge, Ga, and Pb basedon their UV lines in both HZ 44 and HD 127493. In HZ 44 wecould additionally derive abundances for As and Sn based on theFUSE spectrum.In the following we will give a brief overview of the atomic dataand lines used for the abundance measurement of each element.The uncertainties on the abundances can be quite large. This canbe the result of strong blending with unidentified lines, of thesparse atomic data available for most of these elements, and po-tential non-LTE e ff ects. Even if atomic data are available, oscil-lator strengths and line wavelengths are not always well tested.We use data from TOSS for gallium iv - v and data from O’Reilly& Dunne (1998) for Ga iii with updates for two lines fromNielsen et al. (2005). Many Ga lines are observed in theUV spectra of HZ 44 and HD 127493. The strongest, isolatedlines in HZ 44 include Ga iv λλ ffi cult since most lines are relativelyweak and blended with lines from other elements. Neverthe-less, we measured an abundance of log Ga / H = − . ± . / H ≤ − . ± . Germanium shows many lines in the FUSE and IUE spectralrange, including the strong resonance lines Ge iv λλ iii iii - v in HZ 44 which can be matched at an abundance oflog Ge / H = − . ± .
3. (140 times solar). For HD 127493, wederive an abundance of log Ge / H = − . ± . iv iv ar-senic iii lines from low-lying levels, as computed by Marcinek & Migdalek (1993). Oscillator strengths for several optical As iv lines are listed in ALL, originally from Churilov & Joshi (1996).The only ultraviolet As iv line listed in Morton (2000) is theresonance line As iv f = . · − ). Atomic datafor the two resonance lines As v v v oscillator strengths have previously beenused for the As abundance measurement in DO white dwarfsby Chayer et al. (2015) and Rauch et al. (2016a). Morton (2000)also lists a third resonance line, As v S / − P / transition line As v v resonanceline at 1001.211 Å, so we decided to exclude it as well. As iii lines are weak in HZ 44 and As iii λλ / H ≤ − . ± . iv / H = − . v v / H = − . ± . iv / H = − . ± . selenium in the pe-culiar DO white dwarf RE 0503 − v and results from Bahr et al. (1982) forSe iv , as listed in Morton (2000). Se iv λλ v / H = − . ± .
6. However, Se iv / H ≤ − . ± .
4. LikeAs v iv energy levelswe found, Pakalka et al. (2018). Therefore, we adopt an abun-dance of log Se / H = − . ± . zirconium in its optical spectrum. We used the atomic datafrom Rauch et al. (2017a) for our analysis. We fitted four dis-tinct Zr iv lines in the HIRES spectrum of HZ 44 (Zr iv λλ / H = − . ± . iv - v lines, and although none of them are strong or isolatedenough to independently measure the abundance, they are con-sistent with abundance derived from the optical lines. The dou-blet Zr iv λλ / H = − . / H ≤ − . ± . Tin is one of the elements that were identified in HZ 44 byO’Toole (2004). We used atomic data from Safronova et al.(2003), supplemented with data from Biswas et al. (2018) forSn iv and results from Haris & Tauheed (2012) for Sn iii . We de-rived the Sn abundance in HZ 44 to be log Sn / H = − . ± . iv Article number, page 12 of 48. Dorsch et al.: The chemical composition of HZ 44 and HD 127493 − . − . − . . . . . Wavelength (˚ A ) N o r m a li z e d F l u x + O ff s e t . λ λ C a I V A s V Z n I V G e V C u I V C u I V A s V C r V C u I V Z n I V C u I V Fig. 8: As v v / H = − .
8; dashedwithout As. In blue: the adopted abundance log As / H = − .
4. Ingreen: log As / H = − . iv λλ iv iv / H ≤− . ± . iv / H ≤ − . ± . lead iii - v from several sources.Pb iii oscillator strengths are from Alonso-Medina et al. (2009),with the exception of the resonance lines Pb iii iii iv ,we use oscillator strengths from Safronova & Johnson (2004)with additional lines from Alonso-Medina et al. (2011) and oneline (Pb iv v is provided by Colón et al. (2014). While this collection is farfrom complete, many Pb lines could be identified, including notonly strong Pb iii - v lines in the ultraviolet spectrum of HZ 44but also five Pb iv lines in its optical spectrum (Pb iv λλ iv / N too low) results in log Pb / H = − . ± .
09 (11000 times solar). This is remarkably consistent with Pblines observed in the UV region, including lines from Pb iii andPb v . As far as we know, this is the first time Pb v lines weremodeled in any star. The strongest Pb lines per ionization stageobserved in the FUSE spectrum of HZ 44 are shown in Fig. 10.The Pb abundance measurement in HD 127493 is based mostlyon Pb iv / H = − . − . − . − .
25 0 .
00 0 .
25 0 .
50 0 .
75 1 . Wavelength (˚ A ) N o r m a li z e d F l u x + O ff s e t . λ λ λ λ λ λ λ λ Z r I V T i I V G a III Z r I V S i I V S i I V Z r I V O II O II N e II Z r I V Z r I V P b I V S III O III P b I V P b I V P b I V N e II Fig. 9: A selection of Zr iv and Pb iv lines in the HIRES spectrumof HZ 44. In blue: a model with log Zr / H = − . / H = − .
9. In red: the same model, but without Zr or Pb. − . ± .
40 (8400 times solar), consistent with Pb v λλ The abundance measurements for Se, Kr, Sr, Y, Mo, Sb, Te, Xe,and Th turned out to be inconclusive because too few lines werefound and / or their relative line strengths were at variance withmodel predictions. Instead we derived upper limits for theseelements. Krypton and strontium belong to the group of elements that
Article number, page 13 of 48 & A proofs: manuscript no. HZ44_HD127493 − . − . − . − . . . . . . Wavelength (˚ A ) N o r m a li z e d F l u x + O ff s e t . λ λ λ λ F e V S n I V N i V Z n V G a I V C u V P b V C r I V Z n V Z n V Z n V Z n V N i V Z n I V P I V M n III C r III C u I V F e III P b I V C u I V C u I V C u I V C u I V M n V C u I V P b III C u I V Fig. 10: Pb iii , Pb iv , Pb v , and Sn iv lines in the FUSE spec-trum of HZ 44. In blue: a model with log Pb / H = − . / H = − .
9. In red: the same model without Pb and Sn.have been studied in white dwarfs by Rauch et al. (2016b,2017b). Despite the large number of Kr iv - v lines in theTOSS line list, none of them are strong enough in the finalsynthetic spectrum of HZ 44 to be identified in the observation.We derive an upper limit of log Kr / H ≤ − . ± . iv lines, the strongestbeing Kr iv iv / H = − iv λλ v / H ≤ − . ± . strontium in HZ 44. The undetected Sr v iv iv / H ≤ − . ± . iv / H = − . iv λλ / H ≤ − . ± . yttrium in the iHe hotsubdwarf LS IV − ◦ − +
15 (Je ff ery et al. 2017).We used their oscillator strengths for Y iii iii / H ≤ − . ± . / N of the FEROS spectrum and the higher temperaturein HD 127493, the upper limit derived from the same lines inthat star is even higher: log Y / H ≤ − . ± . iii lines for which Redfors(1991) computed oscillator strengths are strong enough toimprove on this threshold. Unfortunately, we found no oscillatorstrength measurements for the resonance lines Y iii iii iv which is the dominant ionizationstage at e ff ective temperatures around 40 000 K.Rauch et al. (2016a) have observed molybdenum inRE 0503 − v and atomicdata from the Kurucz line list for Mo iv to search for Mo inHZ 44. Mo iv λλ v λλ / H = − . / H ≤ − . ± . v λλ v λλ / H ≤ − . ± . antimony in two DO white dwarfs: RE 0503 − + / H ≤ − . ± . iv iv ), Sb v v v tel-lurium ii - iii , including UV and optical lines. However, since theTe iii population numbers are low in HZ 44, none of these linesare visible. Rauch et al. (2017b) provided oscillator strengthsfor Te vi lines, including the resonance lines Te vi λλ / H = − . ± . / H = − . ± . v Article number, page 14 of 48. Dorsch et al.: The chemical composition of HZ 44 and HD 127493 − . − . − . . . . . Wavelength (˚ A ) N o r m a li z e d F l u x + O ff s e t . λ λ F e III M n III A r I V A r I V P I V T e V I M n III C u V C r I V C u I V T e V I Z n V F e III C r I V Fig. 11: Te vi resonance lines in the FUSE spectrum of HZ 44.We show a model with log Te / H = − . / H = − . / H = − . / H = − . v v line. We derive an upper limit of log Te / H = − . ± . xenon iv - v from Rauch et al.(2017a) provided on the TOSS website in order to look forXe in HZ 44. Most Xe lines in the FUSE spectrum of HZ 44are blended with unidentified lines. The resonance linesXe iv λλ v λλ / H ≤ − . ± . v Thorium is the heaviest element for which we found atomicdata. It is of particular interest since it is not produced throughthe s-process and can be used for age determination because ofits radioactivity. Safronova & Safronova (2013) have computedatomic properties of 24 low-lying states of the Th iv ion. Atomicdata for Th iii are published in Safronova et al. (2014), but couldnot be used here since all transitions with calculated oscillatorstrengths lie in the infrared region. Even with a relatively lowabundance of log Th / H = − . iv lines with estimated equivalent widths upto 30 mÅ in the UV range. In particular, the non-detection ofTh iv iv iii line), andTh iv / H ≤ − . / H ≤ − . ± . iv λλ We also searched for predicted lines of Sc, In, Ba, Tl, and Bi inthe ultraviolet and optical spectra of HZ 44. However, no linesfrom these elements could be identified and no meaningful up-per limit could be derived either.The strongest scandium lines in the model of HZ 44 are the reso-nance line Sc iii iii − iii , Sn iv , and Sb v .They predict indium iii lines from low-lying levels with high os-cillator strengths in the IUE spectral region. However, the pop-ulation numbers for In iii are too low to set a meaningful upperlimit for both HZ 44 and HD 127493. Barium was observed in RE 0503 −
289 by Rauch et al. (2014)who also provide atomic data for Ba v . The predicted Ba v linesare so weak in the model of HZ 44 that log Ba / H = − v λλ bismuth line in the spectrum of HZ 44is by far Bi v / H ≤ − . iv but also thallium iii . Similar to In iii , the population numberfor Tl iii is too low to set a meaningful upper limit in both HZ 44and HD 127493. Figures 12 and 13 as well as Table A.5 show our final abundancevalues for HZ 44 and HD 127493. The abundance patterns areremarkably similar in both stars despite the ∼ ff erencein their e ff ective temperature. The overall resemblance betweenthe chemistry of both stars is especially visible when comparingtheir abundances in number fractions (Fig 13). In addition, sometrans-iron elements are present in the atmosphere with very sim-ilar abundances. For example, in HZ 44 Cu, Zn, Ga, Ge, Zr, andPb have the same number fraction of ∼ − . , whereas the so-lar abundances show a strong decrease with increasing atomicmass. As and Sn are significantly less abundant than the othertrans-iron elements.Both stars show a strong CNO cycle pattern, most obvious inFig. 13, with nitrogen being enriched while carbon and oxygenare depleted with respect to solar values. Ne is mildly enriched(by a factor of 3) in both stars compared to solar. With the ex-ception of Cl, all elements with 11 ≤ Z ≤
20 are more abundantin HZ 44 than in the Sun. The abundance of Mg, Al, Si, and Sis similar in both stars. With a measured abundance of 148 + − times solar, the Ti iv lines are very strong in the UVA spectrumof HZ 44. In contrast, the Ti lines covered by the FEROS spec-trum of HD 127493 are weak and set an upper limit for Ti to94 + times solar. Co and Ni have very similar abundances inboth stars: they are about 30 times the solar values. Mn and Cucould not be detected in HD 127493, which indicated that they Article number, page 15 of 48 & A proofs: manuscript no. HZ44_HD127493 are less abundant than in HZ 44. As seen in many other hot subd-warf stars, Fe is the least enriched element among the iron groupin HZ 44 ( ∼ ∼
10 times so-lar) in HD 127493. The Zn abundance in both stars is similar tothat of Ni, between 25 and 30 times solar. While the Ge abun-dances in HD 127493 ( ∼
470 times solar) and HZ 44 ( ∼
140 timessolar) are similar considering uncertainties, the Ga abundancein HD 127493 ( (cid:46)
75 times solar) is lower than in HZ 44 ( ∼ iv and Pb iv lines in their opticalspectrum. As far as we know Zr iv has been identified in the op-tical spectrum of only two iHe hot subdwarfs, LS IV − ◦
7. Discussion
The Carnegie Yearbook No. 55, for 1955 /
56 reports the discov-ery of a new sdO star, BD + ◦ ii , N iii , and Ne ii being especially conspicious. The complete absence of lines ofoxygen and carbon, in any stage of ionization, suggests that thesurface material of this kind of star has undergone nuclear pro-cesses which transformed the carbon into nitrogen and the oxy-gen to neon.” The abundance of those elements derived in pre-vious quantitative spectral analyses as well as in ours substanti-ate this statement. The strong overabundances of heavy elementsfound for HZ 44, HD 127493, and a few other iHe hot subdwarfsstars are generally believed to be caused by atmospheric di ff u-sion processes (radiative levitation). However, it is not plausibleto assume that di ff usion creates an abundance pattern of C, N, O,and Ne, that mimics the nucleosynthesis pattern so well. In thefollowing subsections, we first discuss the evidence for di ff usionprocesses and compare the abundance patterns of our two starsto that of other iHe hot subdwarfs. Then we revisit the nuclearsynthesis aspect and discuss implications for the evolutionarystatus. Di ff usion refers to the equilibrium between gravitational settlingand radiative levitation. While heavy elements are pulled down-wards by gravity, their important line opacities in the UV region,where the photospheric flux distribution peaks, lead to opposingforces due to radiation pressure. This force is limited by the satu-ration of spectral lines at high abundances. Once an equilibriumof both forces has been established, the elemental abundancesshould be fixed.Models that account for gravitational settling and radiative lev-itation only fail to reproduce the observed abundances patternof sdB stars (see Heber 2016, for a discussion). Additional pro-cesses have to be taken into account. Stellar winds and turbulentmixing have been suggested. Michaud et al. (2011) have studiedthe e ff ects of non-equilibrium di ff usion and radiative levitationon element abundances up to Ni for sdB stars on the horizon- tal branch (up to T e ff ≈
37 000 K), but not for sdOs. To matchthe iron abundances observed in sdBs by Geier et al. (2010),and later Geier (2013), they required some process to dampenthe e ff ect of radiative levitation. Michaud et al. (2011) adopteda turbulent surface mixing zone during the HB evolution thatincludes the outer ∼ − . M (cid:12) in the envelope. Similarly to thesdOs discussed in this paper, the photospheric iron abundance insdBs is approximately solar. This low Fe enhancement is a re-sult of its high absolute abundance in the photosphere and theconsequent line saturation (see Fig. 12). Since heavy elements,such as Zr and Pb, are initially less abundant in absolute terms, astronger enrichment due to radiative levitation is expected. Themodels for the hottest stars ( T e ff = −
37 kK) in Michaud et al.(2011) predict abundances that are lower than what is observedin HZ 44 and HD 127493. For example, N, Ne, Al, Si, and Mgare predicted to be depleted with respect to the solar values. Thusadditional processes are required to explain the abundance pat-tern of our two sdOs; nucleosynthesis during the formation of thestars, weak stellar winds (Unglaub 2008; Hu et al. 2011) and apossible atmospheric surface convection zone (Groth et al. 1985;Unglaub 2010) might well be involved.The models by Michaud et al. (2011) can not reproduce the He-enrichment and CNO-cycle pattern observed in some sdBs (andthe sdOs discussed here) since they use approximated methodsto evolve their models through the He-flash. Byrne et al. (2018)have preformed similar calculations for post common envelopesdBs from the top of the RGB to the zero age HB with a moreself-consistent treatment of the He-flash. They produced He-richatmospheres in their delayed He-flash models and predict C andN to be enriched and O to be depleted for sdBs on the zero-agehorizontal branch (ZAHB). The abundances of other elementsare similar to those of Michaud et al. (2011) but both models arenot especially well-suited for the hotter stars discussed here. De-tailed sdO evolutionary models (e. g. through the HeWD-mergerchannel) including di ff usion of heavy elements beyond the irongroup would be required to explain the observed abundance pat-tern. Unfortunately, the atomic data required for modeling di ff u-sion of elements heavier than Ni is still lacking. In Fig. 13 we compared the abundance pattern of HZ 44 andHD 127493 with literature abundances of two other iHe subd-warf stars: [CW83] 0825 +
15 and LS IV − ◦ +
15 is the closest match to HZ 44 and HD 127493in terms of of atmospheric properties with T e ff =
38 900 K andlog g = .
97 (Je ff ery et al. 2017). Although being less He-rich(log n He / n H = − . ∼ + − ◦
116 was the first heavy-metal hot subdwarf to be rec-ognized as so and is considered as the prototype of the class,with its extreme enrichment in Sr, Y and Zr (Naslim et al. 2011)With T e ff =
34 950 K, log g = .
93, and log n He / n H = − . Article number, page 16 of 48. Dorsch et al.: The chemical composition of HZ 44 and HD 127493
H He C N O Ne Na Mg Al Si P S Cl Ar K Ca Ti Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Zr Sn Pb N u m b e r f r a c t i o n ( n X ) SunHD127493HZ44
Fig. 12: Abundance patterns of HD 127493 and HZ 44 compared to that of the Sun (by number fraction). Only elements with anabundance measurement in at least one of the star are shown. Upper limits are marked with an arrow and less saturated colors.[CW83] 0825 + ff erent. However, it is di ffi cult todraw firm conclusions when abundances are known only fora much more limited subset of elements in the other stars. Inthe case of LS IV − ◦
116 and [CW83] 0825 +
15, the lack ofUV data strongly restricts their chemical portrait. Along with[CW83] 0825 +
15, our two stars HZ 44 and HD 127493 are theonly known heavy-metal subwarfs to be enriched in nitrogen,but depleted in carbon and oxygen. The three other known heavymetal subdwarfs have higher C-abundances, similarly to thegroup of CN-rich eHe subdwarfs that is observed at higher tem-peratures. Whether the di ff erences in the the abundances of car-bon and nitrogen in iHe subdwarfs are related to stellar evolutionor the e ff ects of di ff usion remains unclear. The formation of hot subdwarfs with intermediate He abun-dances (10%–90% by number) through merging He-WDs withlow-mass MS stars was investigated by Zhang et al. (2017).In these models, subdwarfs with intermediate He-rich atmo-spheres represent a short ( < ff uses downward (gravitational settling) until the atmo-sphere is H-rich when the ZAHB is reached. The same process ispredicted in accretion-based HeWD + HeWD mergers (Zhang &Je ff ery 2012) that can also reproduce the He abundance in iHe-sds.A known problem is that merger calculations predict afast surface rotation. Schwab (2018) has calculated post-HeWD + HeWD merger models with initial conditions takenfrom hydrodynamic merger calculations and found that mergerproducts have v rot (cid:23)
30 km s − once they appear as hot subd- warfs. This rotation is usually not observed in single sdBs (Geier& Heber 2012) and Hirsch (2009) found N-rich He-sdOs (suchas HZ 44 and HD 127493) to have v rot similar to sdBs. For indi-vidual stars, this can be explained by a small inclination i (whichleads to a small v rot sin i ). However, with increasing evidence forslowly rotating (intermediate) He-sdOs, it seems likely that ad-ditional physics is needed to match the observations (Schwab2018). Alternatively, slowly rotating hot subdwarfs may be cre-ated through a di ff erent process altogether.The observation of the CNO cycle pattern in HD 127493 andHZ 44 indicates that the CNO process must have been e ffi cientin a H-burning shell or mixed from a su ffi ciently hot core in thestars’ progenitor. In fact, the slow HeWD + HeWD merger modelby Zhang & Je ff ery (2012) is able to reproduce the CNO patternobserved in HZ 44 and HD 127493 well except for somewhathigher predicted O-abundances. This may be an indication thatO has been processed to Ne through the α capture O( α, γ ) Ne.In HeWD + MS merger models presented by Zhang et al. (2017),temperatures high enough for O( α, γ ) Ne burning are reachedfollowing the first He-flash, even if the processed material is notalways mixed to the surface. That the He, C, N, O, and Ne abun-dances in some He-sdOs, and in the two stars analysed here, canbe explained by nuclear synthesis might indicate that these lightelements are less a ff ected by di ff usion in this type of stars.An alternative explanation to di ff usion for the extreme enrich-ment of heavy element could be that they were created in thestars’ progenitor. Heavy elements like Zr and Pb are producedmainly in the s-process, which is thought to be e ffi cient inasymptotic giant branch (AGB) stars. While most hot subdwarfsdo not evolve through the AGB phase, low-mass post-AGBtracks are crossing the log g − T e ff diagram in the region pop-ulated by luminous hot subdwarfs (Napiwotzki 2008). Thereforesuch an evolutionary channel might be responsible for a smallfraction of the hot subdwarfs. However, di ff usion calculationsfor these elements are required before conclusions on possibleAGB progenitors of heavy-metal enriched iHe-sds can be made. Article number, page 17 of 48 & A proofs: manuscript no. HZ44_HD127493
HH HeHe CC NN OO FF NeNeNaNaMgMg AlAl SiSi PP SS ClCl ArAr KK CaCa TiTi VV CrCrMnMnFeFe CoCo NiNi CuCuZnZnGaGaGeGeAsAs SeSe KrKr SrSr YY ZrZr MoMoSnSn SbSb TeTe XeXe PbPb ThTh n X / n X HD127493
H He C N O F NeNaMg Al Si P S Cl Ar K Ca Ti V CrMnFe Co Ni CuZnGaGeAs Se Kr Sr Y Zr MoSn Sb Te Xe Pb Th n X / n X HZ44
H He C N O F NeNaMg Al Si P S Cl Ar K Ca Ti V CrMnFe Co Ni CuZnGaGeAs Se Kr Sr Y Zr MoSn Sb Te Xe Pb Th n X / n X [CW83]0825+15 H He C N O F NeNaMg Al Si P S Cl Ar K Ca Ti V CrMnFe Co Ni CuZnGaGeAs Se Kr Sr Y Zr MoSn Sb Te Xe Pb Th n X / n X LSIV-14°116
Fig. 13: Abundance pattern of HD 127493 and HZ 44 with respect to solar composition. Results for the heavy-metal subdwarfs[CW83] 0825 +
15 (Je ff ery et al. 2017) and LS IV − ◦
116 (Naslim et al. 2011) are shown for comparison. Light elements (23 ≤ Z)are marked by green symbols, iron-peak elements (24 ≤ Z ≤
30) in purple, and heavier elements (Z ≥
31) in red. Upper limits aremarked with an arrow and less saturated colors.
8. Conclusion
We have performed a detailed spectroscopic analysis of thetwo intermediate He-sdOs HZ 44 and HD 127493. SED-fitscombined with parallax distances for both stars result inmasses that are consistent with the canonical subdwarf mass of0.47 M (cid:12) within 1- σ uncertainty. No indication of binarity wasfound for either star. Our main focus was the determination ofphotospheric metal abundances, including heavy elements. Wefound the abundance pattern in both stars to be very similar.They show a typical CNO-cycle pattern and slight enrichmentof intermediate-mass elements (Z ≤
30, except Cl) comparedto solar values. Heavier elements such as Ga, Ge, and As werefound to be enriched in the order of 100 times solar. Mostinterestingly, the abundances of Zr and Pb were measured from optical lines and confirmed with UV transitions in HZ 44,and turned out to be more than 1000 and 10000 times solar,respectively. HD 127493 shows no optical Zr or Pb lines, butwe derived a Pb enrichment of about 8000 times solar fromPb iv - v lines in its HST / GHRS UV spectrum. Pb v lines weremodeled for the first time in a stellar photosphere and theirpredicted strength reproduced well the observations of bothstars. We also determined upper limits for several additionalheavy elements. Some of them, for example Xe and Te, have amoderate enrichment ( < ∼
500 times solar) in HZ 44.In order to improve the accuracy of abundance measurements,additional atomic data are much-needed, in particular for theheavy elements. Many lines in both the optical and ultra-violetspectra still remain unidentified. This is especially evident in the
Article number, page 18 of 48. Dorsch et al.: The chemical composition of HZ 44 and HD 127493
FUSE spectrum of HZ 44, where not only interstellar but alsomany photospheric lines are missing from our models. Some ofthose lines likely belong to ionized heavy elements for which noatomic data, or only a limited subset, are available.Interestingly, pulsations were observed in three other iHesubdwarfs, namely [CW83] 0825 +
15 (Je ff ery et al. 2017),LS IV − ◦
116 (Ahmad & Je ff ery 2005), and Feige 46 (Latouret al. 2019). This would make it worth looking for photometricvariability in HZ 44 and HD 127493 as well.As of now, we are not able to fully explain the observedabundance pattern in intermediate He-sdOs. Evolutionarysimulations for sdOs including di ff usion for heavy elementsand mixing during hot flasher / merger evolution would berequired to interpret the abundance pattern. Even though weobtained a quite exhaustive chemical portrait for the two starsanalysed here, this is generally not the case for the other iHehot subdwarfs. More complete set of abundances for additionalstars are also necessary to properly investigate these intriguingpatterns.The e ffi ciency of radiative support on heavy elements in hotsubdwarfs might be linked to their helium abundance, given thatthe intermediate helium-rich hot subdwarfs seem to favorablydisplay extreme enhancements. Hydrogen-rich sdB stars werefound to be enriched in some heavy elements as well (O’Toole& Heber 2006; Blanchette et al. 2008), but their enrichmentin Pb for example is significantly lower than that observed inthe heavy-metal iHe subdwarfs. At the other end of the heliumabundance spectrum, abundance analyses of He-sdOs are morelimited, especially concerning heavy metals. The only He-richsdO for which heavy metal abundances have been derived,BD +
39 3226, turned out the be less than 2 dex enhanced in Zrand Pb (Chayer et al. 2014). It would be most interesting todetermine abundances of heavy elements in additional He-richstars. The He-sdOs recently analyzed by Schindewolf et al.(2018) would be well-suited to confirm (or not) this milder en-richment in heavy metals. Their atmospheric parameters, as wellas their abundances of lighter elements are well constrained,and excellent UV data are available. The current set of hotsubdwarfs for which abundances of heavy elements are knowndo not allow us to rule out the possibility that the e ff ectivetemperature also plays a role in favoring the radiative support ofparticular elements. Once again abundances for a larger sampleof stars across the T e ff range where the extreme overabundancesare observed ( ∼ −
43 kK), also including hydrogen-rich starssuch as the two hottest objects from O’Toole & Heber (2006),will be necessary in order to investigate the relation between T e ff and the (over)abundances of particular elements. Acknowledgements.
We thank Andreas Irrgang and Simon Kreuzer for the de-velopment of the SED fitting tool, Monika Schork for measuring the radialvelocities of HZ 44 from HIRES spectra, and Markus Schindewolf for provid-ing preliminary atmospheric parameters of HZ 44. M.L. acknowledges fundingfrom the Deutsche Forschungsgemeinschaft (grant DR 281 / / ESA Hubble Space Telescope, obtained fromthe data archive (prop. ID GO5305) at the Space Telescope Science Institute.STScI is operated by the Association of Universities for Research in Astron-omy, Inc. under NASA contract NAS 5-26555. Support for MAST for non-HSTdata is provided by the NASA O ffi ce of Space Science via grant NNX09AF08Gand by other grants and contracts. Based on INES data from the IUE satel-lite. Based on observations made with ESO Telescopes at the La Silla ParanalObservatory under programme ID 074.B-0455(A). This research has made useof the Keck Observatory Archive (KOA), which is operated by the W. M.Keck Observatory and the NASA Exoplanet Science Institute (NExScI), undercontract with the National Aeronautics and Space Administration. This workhas made use of data from the European Space Agency (ESA) mission Gaia ( ), processed by the Gaia
Data Process- ing and Analysis Consortium (DPAC, ). Funding for the DPAC has been provided by na-tional institutions, in particular the institutions participating in the
Gaia
Mul-tilateral Agreement. The TOSS service ( http://dc.g-vo.org/TOSS ) used forthis paper was constructed as part of the activities of the German Astrophys-ical Virtual Observatory. We acknowledge the use of the Atomic Line List( ). We also thank the referee, C.Moni Bidin, for his helpful comments.
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Appendix A: Additional material
Appendix A.1: Spectroscopic and photometric dataAppendix A.2: Comparison with literature
Figure A.1 shows the comparison of abundances determined inthis paper with literature values for HZ 44 and HD 127493.The only previous metal analysis of HZ 44 was performed byPeterson (1970) using the curve-of-growth method. Their resultsfor C, N, O, Ne, Mg, Al, Si, and S are consistent with the valuespresented in this paper considering 1- σ uncertainties. Only theirH abundance (based on early ATLAS model atmospheres) andFe abundance (based on three weak optical Fe iii lines with atthe time uncertain oscillator strengths) are overestimated com-pared to ours.Peterson (1970) also performed a curve-of-growth analysis ofoptical spectra for HD 127493 (including C, N, Mg, and Si)which agrees well with the abundances derived here. A similaranalysis was performed by Tomley (1970); his abundance resultsfor C and Ne are higher by about 1 dex while the abundances ofN, Mg, and Si match within the respective uncertainties. C andSi abundance determinations from early NLTE models by Bauer& Husfeld (1995) are higher by ∼ Appendix A.3: Abundances and stellar spectra
This section presents our final abundance values (Table A.5) aswell as a comparison between the full observed and final syn-thetic spectra of HZ 44 and HD 127493 (Fig. A.2 to Fig. A.6).In the synthetic spectra, elements with upper limits only are in-cluded at their upper limit. The synthetic spectra are convolvedwith a Gaussian kernel (constant for GHRS, but wavelength-depended for all echelle spectrographs) to match the resolutionof the respective spectrograph. The strongest photospheric metallines are labeled with magenta marks, interstellar lines are la-beled with green marks. At the bottom of each spectral rangewe also show the residual between the observation and our finalmodel. A proper normalization of the HIRES spectrum of HZ 44was only possible using the final synthetic spectrum as a tem-plate. Thus the shape of broad hydrogen and helium lines in theHIRES spectra is adjusted during the normalization procedure tofit the shape of the synthetic spectrum. However, the shape of thesharp metal lines, that are of interest in the HIRES spectra, arenot a ff ected by the normalization procedure. The optical spec-tra of HZ 44 and HD 127493 are shown up to 6710 Å since thenumber of metal lines at longer wavelengths is very limited. Article number, page 21 of 48 & A proofs: manuscript no. HZ44_HD127493
Table A.1: List of spectra used in our analysis.Star Instrument Dataset Range (Å) Exp. (s) RHD 127493 FEROS ADP.2016-09-21T07:07:18.680 3527 . − . . − . . − . . − . . − . . − . . − . . − . . − . . − . . − . . − . . − . . − . . − . . − . . − . . − . . − . . − . . − . − − − − − − . − . . − . . − . . − . . − . Article number, page 22 of 48. Dorsch et al.: The chemical composition of HZ 44 and HD 127493
Table A.2: Radial velocity measurements for HZ 44 and HIRES spectra used.Time (
YYYY-MM-DD hh:mm ) Number of considered lines v rad (km s − )1995-07-02 05:26 10 12 . ± . . ± . . ± . . ± . . ± . . ± . . ± . . ± . . ± . . ± . . ± . . ± . . ± . . ± . . ± . . ± . . ± . . ± . . ± . . ± . . ± . . ± . . ± . . ± . . ± . . ± . . ± . Article number, page 23 of 48 & A proofs: manuscript no. HZ44_HD127493
Table A.3: Photometric data used for the SED-fit of HZ 44.System Passband Magnitude Uncertainty Type Reference2MASS H 12.569 0.023 magnitude (Cutri et al. 2003, 2MASS: II / / out)2MASS J 12.386 0.022 magnitude (Cutri et al. 2003, 2MASS: II / / out)2MASS K 12.672 0.027 magnitude (Cutri et al. 2003, 2MASS: II / / out)Stroemgren H β / A + A / / A23 / catalog)Stroemgren b − y − .
151 color (Paunzen 2015, J / A + A / / A23 / catalog)Stroemgren m1 0.104 0.020 color (Paunzen 2015, J / A + A / / A23 / catalog)Stroemgren y 11.715 0.007 magnitude (Paunzen 2015, J / A + A / / A23 / catalog)UKIDSS H 12.560 0.002 magnitude (Lawrence et al. 2013, UKIDSS DR9: II / / las9)UKIDSS J 12.400 0.001 magnitude (Lawrence et al. 2013, UKIDSS DR9: II / / las9)UKIDSS K 12.687 0.002 magnitude (Lawrence et al. 2013, UKIDSS DR9: II / / las9)UKIDSS Y 12.276 0.001 magnitude (Lawrence et al. 2013, UKIDSS DR9: II / / las9)WISE W1 12.750 0.023 magnitude (Cutri & et al. 2012, AllWISE: II / / allwise)WISE W2 12.830 0.025 magnitude (Cutri & et al. 2012, AllWISE: II / / allwise)IUE box 1300 − / / inescat, SWP03432LL)IUE box 2000 − / / inescat, LWR03017LL)IUE box 2500 − / / inescat, LWR03017LL) Gaia
G 11.6350 0.001 magnitude (Gaia Collaboration 2018, I / / gaia2) Gaia
GBP 11.3913 0.007 magnitude (Gaia Collaboration 2018, I / / gaia2) Gaia
GRP 11.9377 0.001 magnitude (Gaia Collaboration 2018, I / / gaia2)Johnson V − I − .
322 0.002 color (Landolt & Uomoto 2007b, J / AJ / / / table4)Johnson R − I − .
181 0.001 color (Landolt & Uomoto 2007b, J / AJ / / / table4)Johnson V − R − .
141 0.001 color (Landolt & Uomoto 2007b, J / AJ / / / table4)Johnson B − V − .
291 0.001 color (Landolt & Uomoto 2007b, J / AJ / / / table4)Johnson U − B − .
196 0.003 color (Landolt & Uomoto 2007b, J / AJ / / / table4)Johnson V 11.673 0.002 magnitude (Landolt & Uomoto 2007b, J / AJ / / / table4) Article number, page 24 of 48. Dorsch et al.: The chemical composition of HZ 44 and HD 127493
Table A.4: Photometric data used for the SED-fit of HD 127493.System Passband Magnitude Uncertainty Type Reference2MASS H 10.816 0.028 magnitude (Cutri et al. 2003, 2MASS: II / / out)2MASS J 10.641 0.023 magnitude (Cutri et al. 2003, 2MASS: II / / out)2MASS K 10.907 0.025 magnitude (Cutri et al. 2003, 2MASS: II / / out)Johnson B − V -0.234 color (Mermilliod 2006, II / / ubvmeans)Johnson U − B -1.17 color (Mermilliod 2006, II / / ubvmeans)Johnson V 10.05 magnitude (Mermilliod 2006, II / / ubvmeans)Stroemgren H β / A + A / / A23 / catalog)Stroemgren b − y -0.114 0.003 color (Paunzen 2015, J / A + A / / A23 / catalog)Stroemgren c1 -0.214 0.013 color (Paunzen 2015, J / A + A / / A23 / catalog)Stroemgren m1 0.048 0.002 color (Paunzen 2015, J / A + A / / A23 / catalog)Stroemgren y 10.035 0.009 magnitude (Paunzen 2015, J / A + A / / A23 / catalog)WISE W1 10.954 0.023 magnitude (Cutri & et al. 2012, AllWISE: II / / allwise)WISE W2 11.045 0.021 magnitude (Cutri & et al. 2012, AllWISE: II / / allwise)IUE box 1300-1800 6.306 0.02 magnitude (Wamsteker et al. 2000, VI / / inescat, SWP08275LL)IUE box 2000-2500 7.164 0.02 magnitude (Wamsteker et al. 2000, VI / / inescat, LWR07210LL)IUE box 2500-3000 7.547 0.02 magnitude (Wamsteker et al. 2000, VI / / inescat, LWR07210LL) Gaia
G 9.9636 0.0011 Magnitude (Gaia Collaboration 2018, I / / gaia2) Gaia
GBP 9.8227 0.0038 Magnitude (Gaia Collaboration 2018, I / / gaia2) Gaia
GRP 10.2446 0.0015 Magnitude (Gaia Collaboration 2018, I / / gaia2)Johnson B − V -0.258 color Menzies et al. (1990)Johnson U − B -1.165 color Menzies et al. (1990)Johnson V 10.01 magnitude Menzies et al. (1990)Johnson B − V -0.269 color Kilkenny et al. (1998)Johnson U − B -1.184 color Kilkenny et al. (1998)Johnson V − R -0.115 color Kilkenny et al. (1998)Johnson V − I -0.276 color Kilkenny et al. (1998)Johnson V 10.039 magnitude Kilkenny et al. (1998)
Article number, page 25 of 48 & A proofs: manuscript no. HZ44_HD127493
H He C N O F NeNaMgAl Si P S Cl Ar K Ca Ti V CrMnFeCo Ni CuZnGaGeAsSe Kr Sr Y ZrMoSnSbTeXePbTh N u m b e r f r a c t i o n r e l . t o s o l a r ( n X / n X ) HZ44HZ44_Peterson1970
H He C N O Ne Na Mg Al Si P S Ar Ca Ti Cr Mn Fe Co Ni Cu Zn Ga Ge Kr Sr Y Zr Mo Sn Te Pb Th N u m b e r f r a c t i o n r e l . t o s o l a r ( n X / n X ) HD127493HD127493_Peterson1970HD127493_Tomley1970HD127493_Simon1980HD127493_Bauer1995HD127493_Hirsch2009
Fig. A.1: Same as Fig. 13 but for the comparison of abundances derived in this paper with literature values.
Article number, page 26 of 48. Dorsch et al.: The chemical composition of HZ 44 and HD 127493
Table A.5: Abundances of HZ 44 and HD 127493 as derived from visual / UVA and FUV data.Abundance (log n X / n H ) Mass fraction ( β X ) Number fraction (log n X ) Abundance (log n X / n X , (cid:12) )Element HZ 44 HD 127493 HZ 44 HD 127493 HZ 44 HD 127493 HZ 44 HD 127493
H 0.00 + . − . + . − . -0.79 + . − . -1.26 + . − . -0.36 + . − . -0.71 + . − . -0.32 + . − . -0.68 + . − . He 0.10 + . − . + . − . -0.09 + . − . -0.03 + . − . -0.26 + . − . -0.09 + . − . + . − . + . − . C -4.31 + . − . -4.30 + . − . -4.02 + . − . -4.48 + . − . -4.67 + . − . -5.01 + . − . -1.06 + . − . -1.41 + . − . N -2.39 + . − . -2.08 + . − . -2.03 + . − . -2.19 + . − . -2.74 + . − . -2.80 + . − . + . − . + . − . O -3.90 + . − . < -4.30 + . -3.49 + . − . < -4.35 + . -4.26 + . − . < -5.01 + . -0.91 + . − . < -1.67 + . F < -5.00 + . < -4.51 + . < -5.36 + . < + . Ne -3.23 + . − . -2.90 + . − . -2.72 + . − . -2.85 + . − . -3.59 + . − . -3.61 + . − . + . − . + . − . Na -4.43 + . − . < -3.40 + . -3.86 + . − . < -3.29 + . -4.79 + . − . < -4.11 + . + . − . < + . Mg -3.80 + . − . -3.39 + . − . -3.20 + . − . -3.26 + . − . -4.16 + . − . -4.10 + . − . + . − . + . − . Al -4.86 + . − . -4.53 + . − . -4.21 + . − . -4.35 + . − . -5.21 + . − . -5.24 + . − . + . − . + . − . Si -3.88 + . − . -3.31 + . − . -3.22 + . − . -3.11 + . − . -4.24 + . − . -4.02 + . − . + . − . + . − . P -5.66 + . − . -4.70 + . − . -4.96 + . − . -4.46 + . − . -6.02 + . − . -5.41 + . − . + . − . + . − . S -3.87 + . − . -3.90 + . − . -3.16 + . − . -3.65 + . − . -4.23 + . − . -4.61 + . − . + . − . + . − . Cl -7.50 + . − . -6.74 + . − . -7.86 + . − . -1.32 + . − . Ar -3.79 + . − . < -3.60 + . -2.98 + . − . < -3.25 + . -4.15 + . − . < -4.31 + . + . − . < + . K -4.91 + . − . -4.11 + . − . -5.27 + . − . + . − . Ca -3.90 + . − . < -3.90 + . -3.08 + . − . < -3.55 + . -4.25 + . − . < -4.61 + . + . − . < + . Ti -4.56 + . − . < -4.40 + . -3.67 + . − . < -3.98 + . -4.92 + . − . < -5.11 + . + . − . < + . V < -4.80 + . < -3.88 + . < -5.16 + . < + . Cr -4.40 + . − . -3.90 + . − . -3.47 + . − . -3.44 + . − . -4.76 + . − . -4.61 + . − . + . − . + . − . Mn -4.90 + . − . < -5.50 + . -3.95 + . − . < -5.02 + . -5.26 + . − . < -6.21 + . + . − . < + . Fe -4.00 + . − . -2.82 + . − . -3.04 + . − . -2.33 + . − . -4.36 + . − . -3.53 + . − . + . − . + . − . Co -5.60 + . − . -5.30 + . − . -4.62 + . − . -4.78 + . − . -5.96 + . − . -6.01 + . − . + . − . + . − . Ni -4.05 + . − . -3.61 + . − . -3.07 + . − . -3.10 + . − . -4.41 + . − . -4.33 + . − . + . − . + . − . Cu -5.80 + . − . < -6.10 + . -4.79 + . − . < -5.55 + . -6.16 + . − . < -6.81 + . + . − . < + . Zn -5.70 + . − . -5.30 + . − . -4.67 + . − . -4.74 + . − . -6.06 + . − . -6.01 + . − . + . − . + . − . Ga -6.00 + . − . < -6.40 + . -4.95 + . − . < -5.81 + . -6.36 + . − . < -7.11 + . + . − . < + . Ge -5.90 + . − . -5.00 + . − . -4.83 + . − . -4.39 + . − . -6.26 + . − . -5.71 + . − . + . − . + . − . As -7.40 + . − . -6.31 + . − . -7.76 + . − . + . − . Se -6.30 + . − . -5.19 + . − . -6.66 + . − . + . − . Kr < -5.20 + . < -4.80 + . < -4.07 + . < -4.13 + . < -5.56 + . < -5.51 + . < + . < + . Sr < -5.10 + . < -4.90 + . < -3.95 + . < -4.21 + . < -5.46 + . < -5.61 + . < + . < + . Y < -5.30 + . < -4.70 + . < -4.14 + . < -4.01 + . < -5.66 + . < -5.41 + . < + . < + . Zr -5.92 + . − . < -5.30 + . -4.75 + . − . < -4.60 + . -6.28 + . − . < -6.01 + . + . − . < + . Mo < -6.20 + . < -6.10 + . < -5.01 + . < -5.37 + . < -6.56 + . < -6.81 + . < + . < + . Sn -6.90 + . − . < -6.60 + . -5.61 + . − . < -5.78 + . -7.26 + . − . < -7.31 + . + . − . < + . Sb < -8.00 + . < -6.70 + . < -8.36 + . < + . Te < -7.10 + . < -5.80 + . < -5.78 + . < -4.95 + . < -7.46 + . < -6.51 + . < + . < + . Xe < -7.30 + . < -5.97 + . < -7.66 + . < + . Pb -5.89 + . − . -5.65 + . − . -4.36 + . − . -4.59 + . − . -6.25 + . − . -6.36 + . − . + . − . + . − . Th < -8.00 + . < -7.80 + . < -6.42 + . < -6.69 + . < -8.36 + . < -8.51 + . < + . < + . Notes.
Abundances are given as logarithmic number ratio of element X relative to hydrogen log n X / n H , logarithmic mass fraction β X , logarithmicnumber fraction log n X , and logarithmic number fraction relative to solar values log n X / n X , (cid:12) . Uncertainties are given as standard deviation betweensingle line fits. If an abundance was “fit by eye” the uncertainties are similarly estimated. The He abundance for HD 127493 is from Hirsch (2009).Article number, page 27 of 48 & A proofs: manuscript no. HZ44_HD127493 . . . . . . . . NormalizedFlux D I H I D I H I O I O I D I H I O I O I D I H I O I O I D I H I O I O I D I H I H H O I D I H I O I D I H I O I MnIII PbIV FeIII MnIII PIVNIII PIII MnIII MnIII NIII PbV XeIV MoIV CrIV PIII MoIV NIV PbIV CrIII PbIV NIV CrIII NiIII CrIV NIVMoIV CoIII NIV CrIII NIVMnIII SIVCrIII SVNIV CrIII CrIII CoIII CrIII MnIII MnIII XeIV CrIV CrIII MnIII CrIII CrIV SIVPbIV FeIII SIV FeIII MoIV FeIII NIII FeIII SIVMoIV MoIV CrIV CaIV PbIV CrIV SVI FeIII CaIV XeIV XeV CoIII PbV CrIV MoIV CoIII SII FeIII MnIII MoIV MnIII NIII CoIII MoIV NIII GaIV CaIV CrIV NIII CoIII SiIII MoIV SIVMoIV SIV FeIII CoIII NIII NIII NIII CrIII MnIII MnIII SVI CoIII XeV MnIII FeIII PbV SIV SIVGaIV NIII ArIV ArV CoIII NIII NIV SIVNIV NIV FeIII NIII NIV NIV CaIV SIVNIII MnIII FeIII MnIII ArIV SIV SIV FeIII MnIII ArIV ArIV PIV FeIII TeVI MnIII CaIV − − Residuals . . . . . . NormalizedFlux N I N I N I N I N I N I N I N I N I N I H H O I O I D I H I H I H I O I H O I F e II MnIII GaIV PbV CoIII NiIV PbV NiIII ZnIV NIVMoIV FeIII CaIV MnIII ArIV GaIV NIII NIII GaIV NIII NIII NIII MnIII MoIV MnIII SeIV NIII MoIV CaIV NIII FeIII CaIV SrVOIII FeIII ArV SIVZnIV MnIII CrIII KrIV SIVCuIV CaIV GaIV SIVCrIII FeVMoIV FeV FeIII NiIV ZnIV CrIII CaIV OIII SiIII NIII NIII NiIII CrV FeIII CrIII CaIV PbV NiIII NiIII MoIV GeV SIVMnIII CrIV FeIII MnIII PIII ZnIV GaIV ClIV FeIII NiIII ZnIV NII NII NII ZnIV CaIV NIII NIII NIII ArIV ArIV ZnIV GaIV NIII NIII NIII ZnIV PbV CIII ClIV ZnIV PIII ClIV FeV FeIII ZnIV ZnIV NiIII FeIII NIII NIII NIII MnIII NIII ArIV CaIV ZnIV ArIV PbV FeV FeIII GaIV ArIV ArIV FeV CrV FeV FeV ArIV KrIV ZnIV ZnIV NIII FeV FeIII FeIII FeV ZnIV ClIV ZnIV NIII − − Residuals . . . . . . NormalizedFlux A l II H O I S i II H H H H H H NIII ClIV FeIII FeIII NiIV CrV ArIV ClIV ZnIV FeV FeIII FeIII GaIV AsV ZnIV FeIII FeV ZnIV FeIII FeIII NIII ArIV FeIII ZnIV FeIII CrIV FeIII FeIII NIII NIII FeIII MnIII CrIII ZnIV FeIII ZnIV SiIII FeV FeIII FeIII SiIII FeVMoIV FeIII FeV SeIV FeIII SiIII FeV FeIII PVFeV PIII FeV NIV CrIII FeIII KrIV SIV FeV PVZnIV ZnIV CrIII ZnIV CrIII CaIV FeV SeIV NIII NIII ZnIV ZnIV ArIII NIII NIII CrIII CrIII ZnIV NIII XeIV PIII GeV ZnIV TiIII SiIII NIV NIII NIII SIVPIVNIV SIVVIII FeV FeV NIII NIII OIII ZnIV ZnIV FeV ZnIV GaIV CuIV ZnIV CII ArIV ArIV FeV FeV ZnIV ArIV FeV SIII MnIII ArIV FeV ArIV SIII SIII CrIII SIII ArIV CrIII GeV FeV CrIII FeIII CrIII ZnIV FeV CrIII MnIII FeIII FeV ZnIV FeIII ZnIV CuIV − − Residuals . . . . . . NormalizedFlux S i II D I H I H I H I O I H C II C II F e II H O I H H H A r I H H H H SnIV FeIII CuIV FeV SIV FeV SIII ArIV SIII NIII FeIII ZnIV FeV FeIV SIVCuIV ZnIV PIV CrIII CrIII ArIV SIV FeIII SIVArIV PIV CrIII FeIII PbIV CuIV AsV CrV CuIV ZnIV CrIII PIV PIV ZnIV CrIII FeIII CrV CuIV CuIV PbIV FeIII PIV CuIV FeIII CrIII FeIII CrIII CrV CuIV CrIII CrIII CrIII SiIII NIII FeIII NIII CrIII CrV CrIII PIV CrIII SIV FeIII CrIII CrIII CrIII NIV NIV NIV CuIV NIV NIV CII ArIV CII SiIII ZnIV CrIII CrV ArIV CrIII FeIII GeV NIII CrIII NIII NIII ArIV SVCrIII ArIV OIII CrIII CuIV CrIII CrIII MoIV SbIV CrIV CrV CrV ArIV CrIV CuIV ZnIV MnV CuIV SnIV CuIV NIII CrV CrIII GeV CrV CrV CrV CuIV CrV FeIV CrV CrV CuIV MnV PbIII NIII CuIV GeV NIII CuIV NIII CrV PbV CuIV NIII NIII NIII W a v e l e n g t h ( ˚ A ) − − Residuals
Fig. A.2: FUSE spectrum of HZ 44 (gray) and the final model (red, with heavy metals: blue).
Article number, page 28 of 48. Dorsch et al.: The chemical composition of HZ 44 and HD 127493 . . . . . . . . NormalizedFlux F e II H F e II H F e II F e II H A r I H H H H H F e II F e II N II CuIV CrIV GeV CuIV CrIII NIII MnV NIII NIII ZnIV CuIV CuIV CrV NiV CrIV CrIII CuIV CrIV CrIII CrV CrIV CrIII ZnV CrIV CuIV FeIII SIVCrIII CrIV NII CrIV FeIII FeIV ZnV CuIV CrIII CrIII FeIII PIV PIV CrIV PIV PIV PIV CuIV CII FeIII FeIII FeIII CrIII SiIV SiIV PIV PIV SiIV CrIII OIV OIV FeIII CrIII GeV CrIV CrIV FeIII GeV CuIV CrIV FeV ZnV CrIV NIV NIV CrIV VIV CrIV TeVI FeIII CrIV CrIV CrIV CrIII CrIV GeV SIVCrIV CrV SIVCuIV CuIV CuIV CrIV CrIV ZnV CuIV CrIV CrIV CuIV SIII CrIV CrIV NiIV CuIV NIV CrIV CrIV OIII CrIV NiIV CrIV CrIV CrIV CrIV CrIV SiIV CrIV SiIII NiIV CrIV NII SiIII CrIV MnIII NII NII NIII NIII CrIV NII NII FeIII NIIMnIII MnIII NIV NIII NIII VIV GeV NIV FeIII − − Residuals . . . . . . . NormalizedFlux H H H F e II H H H F e II NIII GeV CrIV SIVGeIII PIV PIV ZnV PbV NIII NIII FeIII GeV CrV FeIII CrIV CrIV NIII NIII CrIV NIII SIVCrIV NIII NIII NIII PIV PIVNIII SIVCrIV SIV SeV NIII NiIV NIII CrIV VIV NIII NIII PbV FeIII CrIV NIII NIII FeIII SIV SIVVIII CrIII SIV SIVCrIII CrIV CrIII CuIV NIII CrIV NIII CrIV NIII NIII SbV CrV NIV PbV CrIV CrIV NIII CrV NIII SIVCIV SIVCIVMnIII SiIII SIVCrIV VIV SIV SiIII SiIII CrIV CrIV CrIV VIV CrIV SIV SIVVIII SIVMnIII SIVVIII VIV VIV CrV CrIV FeV SIVMnIII SiIII MnIII SiIII SIV SIVMnIII SiIII CrIII NiIV CrV VIV NiIV VIV VIII PbIV CrV ZnV GeV PIV SIVCrIII SIVCrV VIV CuV SIVPVCrV CrIII CrIII PIVNIII SnIV NIII NIII SIVCrIV NIII − − Residuals . . . . . . NormalizedFlux F e II F e II F e II F e II N I N I N I C I F e II F e II F e II F e II F e II F e II F e II F e II F e II F e II F e II F e II O I NIII NiIV NiV NiIV NIII CrV VIV CuV NIII SIV SVVIII VIV CrV SIII CrIII SiIV FeIII VIII CrIV KrIV VIV VIII NiIV NiV FeIII VIII CrV NiIV CrIV FeIII SIII CrV VIV PVFeIII NiIV NiIV SiIV SiIV SIII VIII FeIII CuV CrIV FeIII FeIII FeIV CrIV FeIII VIV NIV NIV NIV ZnV NIV CrV NIV ZnV NIV ZnV ZnV NiIV SVSVSVCrV NiV NIV NIII NIII NIV NiIV ZnIV CrIII GaIV PbV CrV CrIV PbIV MoV CrIV SIV SIVOIII VIII BiVNIII NIII NIII CrV SiIII FeIII SiIII SIVCrIV SiIII FeIII VVZnV FeIII NiIV CaIV NiV FeIII SiIII CrIII NiIV NIII NIII PbIV SiIII NIII SiIII SiIII SiIII SiIII SiIII ZnV CrIV NiIV MoV CuV ZnV OIII ZnV VIII OIII CrIV SeV VIII NiV VIII NiV ZnV VIII OIII VIII SiIV SiIV − − Residuals . . . . . . NormalizedFlux C I S I S I C I C I C I C I S I S I N I S I N I S I S II N I N I SiIII SIII CuV NiIV ZnIV SiIII GaIV FeIV SiIII MnV VIII CuV CuV VVPbV CuV SiIII CrIV CuV ZnV CuV NiV NiV VVCuV NIII SiIII CuV VIII MoV CrIII SiIII VIII CrIV CuV GaIV NiV NiV CrIV CIII VIII NiV CuV CuV MoV NIV CuV NIV NiV CIV CIVNIV NIV NIV NIV GaIV CaIV CuV ZnIV CuV CuV CrIV CuV CuV ZnV VIV ZnV NiV ZnV NiIV MoV CrIII CIII CIII CuV MoV CIII CIII FeIII CIII CIII CuV ZnV ZnV FeIV ZnV ZnV ZnV CrIV CrIV ZnIV NiIV CuV VIV SiIII ZnV NiV ZnIV CuV VIV NiV ZnV NiV VIV VIV SiIII ZnIV CuV CuV NiV NIII NIII CrIV TiIV ZrIV FeIV NIII NIII GaIV PbV CrIV ZnV ZnV ZnV ZnV NiVMoV GaIV MoV ZnV NIII NIII CrIII ZnV ZnV ArIV NIV CuV SrIV CuV W a v e l e n g t h ( ˚ A ) − − Residuals
Fig. A.2 (continued): FUSE spectrum of HZ 44 (gray) and the final model (red, with heavy metals: blue).
Article number, page 29 of 48 & A proofs: manuscript no. HZ44_HD127493 . . . . . . . . NormalizedFlux F e II O I C I S I S I C I C I C I C I S I S I N I S I N I S I S II N I N I S i II S i II N I N I N I S i III D I H I H I H I S II S II VIII VIII OIII VIII SiIII SiIII VIII VVPbV SiIII SiIII VIII CrIII SiIII VIII CrIV CrIV CIII NIV CIV CIVNIV NIV GaIV VIV CIII CIII CIII CIII CIII CIII NIII NIII TiIV ZrIV NIII NIII GaIV CrIV NIII NIV GeIV PbV SIII GaIV NiIV NiIV GaIV NIII SIII SIII VIV NIII GaIV TiIV NIII CrIV NIV NIV NIII NIV NIV SIVNIII CrIV SIV SVSIII CrIV GaIV SIII ZrIV NiIV CrIII SiIII SiIII GaIV CrIV SiIII CrIII CrIV CrIV SiIII SiIV CrIII ArIV SiIII CrIV PbV CrIV CrIV NiIV CrIV ZrIV CrIV CrIV CrIV CrIV ZnIV NIV SbV VIV SIV SIV SIV SIVGaIV ZnIV GeIV SiIV CrIII NiIV SiIII CrIII CrIV GaIV NVMnIV NVSrIV NiVMnIV NIII GaIV NiIV CrIV CIII MnIV FeIV SIVCrIV NiV CrIV SIVMnIV VIII CrIII CrIV FeIV VIII − − Residuals . . . . . . NormalizedFlux S II S i II C I O I S i II C II C II C II MnIV SIVGaIV SIVZnIV NIV NIV NII NII NII SiIV SIV SIVTiIII CrIV NIII CrIV NIII NIII CrIV NIII CrIV TiIII SiIII TiIII TiIII SIVGaIV TiIII CIII CIII SIV SIV SiIII CaIII TiIII SiIII SiIII SIVCrIV SiIII SiIII GaIV VIV CrIV CrIV ZnIV CrIV VIV NIV CrIV CrIV NiIV NIII SiIII VIV PbIV PbIV PbIV NIII SnIV NiIV CrIV NIII NIII NIII VIV NiIV NIII NiIV SIVCrIV VIV NiIV NIII NIII NIII NIII NIII NiIV CrIV CrIV SIVTiIII NiIV CrIV NiIV CIII VIV CrIV CrIV VIII CrIV NiIV CrIV CrIV VIV CII VIII CaIII CII CrIV NiIV NiIV CrIV GaIV OIV NiIV NiIV CrIV CrIV NiIV CrIV CrIV SiIII SiIII OIV SiIII OIV PIII NIII NiIV NIII NiIV NIII NIII NIII CrIV CrIV SiIV ZnIV NiIV CrIV CrIV CrIV CrIV VIV CrIV NiIV NiIV − − Residuals . . . . . . NormalizedFlux N i II NiIV SiIII CrIV SIVNiIV SiIII NiIV SiIII SIVNiIV NiIV NiIV CrIV NiIV AlIII CrIV NiIV NiIV AlIII NiIV NIII NIII NIII NIII NIII NiIV SiIV VIV NiIV NiIV NiIV NiIV NiIV NiIV VIV NiIV NiIV NiIV NiIV SiIV VIV SIV SIVNiIV NiIV NIII NIII NiIV NiIV NiIV NiIV NiIV SIVNiIV SiIII NiIV CrIV NiIV NiIV NiIV NiIV NiIV VIV NiIV NiIV TiIII NiIV SIVNiIII FeIV FeIV NiIV NiIV CIII VIV FeIV FeIV NiIV NiIII NiIV VIV NiIV NiIV FeIV NiIV NiIV FeIV NiIV NiIV NiIV NiIII VIV NiIV NiIV NiIV NiIV NiIV SnIV NiIV NiIV NiIV NiIV NiIV NiIV NiIV NiIV NiIV NiIV NiIV NiIV NiIV FeIV NiIV NiIV NiIV NiIV NiIV NiIV NiIV NiIV NiIV NiIV NiIV NiIII TiIV NiIV NiIV FeIV CaIII NiIV NiIV NiIV NiIV TiIII NiIV NiIV NiIV NiIV NiIV FeIV − − Residuals . . . . . . NormalizedFlux S i II C I NiIV NiIV NiIV NiIV CaIII NiIV TiIV NiIV NiIV TiIV NIII NIII NIII NIII NiIV NiIV NiIV NiIV NiIV NiIV NiIV NiIV NiIV NiIV FeIV NiIV CaIII NiIV NIV NiIV NiIV NiIV NiIV NiIV NiIV NiIV NiIV GaIII NiIV NIII NiIV NIII TiIII NiIV NiIV NiIV NiIV NiIV NiIV NiIV SiIII SiIII SiIII SVSiIII CoIV NiIV NiIV NiIV NiIV GaIII NiIV NiIV NiIV NiIV NiIV CoIV FeIV NiIV NiIV FeIV FeIV NiIV NiIV NiIV NiIV FeIV FeIV NiIV FeIV FeIV SiIV SiIV FeIV FeIV FeIV CoIV GaIII NiIV NiIV FeIV NiIV NiIV FeIV NiIV FeIV NiIV NiIV FeIV NiIV NiIV NiIV NiIV NiIV FeIV CaIII NiIV NiIV FeIV NiIV CIVNiIV FeIV NiIV FeIII CIV FeIV FeIV FeIV FeIV NiIV NiIV CaIII FeIV NiIV FeIV NiIV FeIV NiIV FeIV NiIV NiIV NiIV FeIV NiIV NIII FeIV FeIV CaIII FeIV W a v e l e n g t h ( ˚ A ) − − Residuals
Fig. A.3: IUE spectrum of HZ 44 (gray) and the final model (red, with heavy metals: blue).
Article number, page 30 of 48. Dorsch et al.: The chemical composition of HZ 44 and HD 127493 . . . . . . . NormalizedFlux F e II C I FeIV FeIV FeIV FeIV FeIV NiIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV NIII FeIV FeIV CIII FeIV SIII FeIV FeIV ZnIII NiIV NiIV NiIV FeIV FeIV FeIV FeIV FeIV NiIV FeIV FeIV FeIV FeIV FeIV FeIV CoIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV AlIII FeIV NiIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV MnIV FeIV AlIII AlIII NiIV CoIV NiIII NIII FeIV FeIV FeIV FeIV ArIII FeIV FeIV FeIV FeIV FeIV FeIV CIII CIII NiIII FeIV FeIV FeIV FeIV FeIV SIV SIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV SIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV SiIV SiIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV CIII FeIV FeIV NiIII FeIV NiIII FeIV MnIV FeIV NiIII MnIV FeIV FeIV CrIV FeIV FeIV FeIV FeIV FeIV NiIII FeIV FeIV FeIV MnIV MnIV − − Residuals . . . . . . NormalizedFlux A l II N i II MnIV MnIV FeIV ArIII FeIV ArIII MnIV FeIV CrIV FeIV ArIII ArIII FeIV ArIII FeIV NII NII FeIV FeIV FeIV FeIV NiIII SIV SIV FeIV FeIV CrIV NiIII MnIV FeIV FeIV FeIV NIII MnIV MnIV MnIV FeIV NIII MnIV NIII CrIV NIII NIII FeIV FeIV NiIII CrIV NiIII FeIV NiIII NiIII NiIII MnIV FeIV NiIII FeIV NiIII FeIV FeIV NiIII NiIII NiIII NiIII FeIV FeIV FeIV NiIII NIVMnIV NiIII FeIV MnIV MnIV NiIII MnIV NiIII SiIV SiIV FeIV MnIV NiIII FeIV FeIV NiIII MnIV CrIV FeIV CrIV SiIV NIII NIII NIII NIII NiIII NIII NIII CrIV NIII FeIV NiIII CrIV NiIII NiIII NiIII SIVCrIV NII CrIV NiIII MnIV NII CrIV SIVCrIV NiIII CrIV NiIII NIII NIII NIII MnIV NIII NiIII NiIII CrIV CrIV CrIV CrIV MnIV NiIII FeIV CrIV MnIV NIII NiIII NiIII FeIV NIII MnIV NiIII − − Residuals . . . . . . NormalizedFlux S i II NiIII CrIV NiIII NiIII MnIV CrIV MnIV NiIII NiIII MnIV CrIV CrIV CrIV CrIV NiIII FeIV NiIII MnIV NiIII MnIV NiIII MnIV NiIII SIV SIVMnIV NiIII NiIII MnIV NiIII MnIV NiIII CrIV NiIII CrIV FeIV NiIII NiIII MnIV MnIV CrIV FeIV CrIV FeIV NIII CrIV NiIII NIII NIII FeIV NIII CrIV VIV NiIII NIII FeIV CaIII CrIV CrIV FeIV VIV FeIV NiIII CrIV VIV FeIV NiIII CaIII CrIV VIV CrIV VIV CrIV NiIII FeIV FeIV CrIV CrIV NiIII CrIV CrIV VIV CrIV CrIV CrIV FeIV NiIII CrIV CaIII NiIII CrIV FeIV CrIV ArIII CrIV CrIV ArIII CrIV FeIV SiIII CrIV CrIV ArIII FeIV NiIII CrIV NIII NIII NIII NIII NIII NIII NIII NIII NIII NiIII CrIV NiIII NiIII CrIV FeIV CrIV NiIII AlIII CrIV ArIII FeIV NIII NiIII FeIV FeIV VIV CrIV AlIII CrIV CrIV CrIV CrIV FeIV CaIII − − Residuals . . . . . . NormalizedFlux
CaIII FeIV CrIV CrIV FeIV FeIV FeIV CrIV FeIV FeIII ArIII TiIII FeIII CrIV FeIV NIII FeIII NIII NIII FeIII FeIII PIVMnIV FeIII FeIII FeIII FeIII FeIV MnIV FeIII TiIII NiIII CrIV CrIV NIII MnIV NIII FeIII NIII NIII CrIV CaIII MnIV FeIII SIV FeIII ArIII FeIII ArIII SIV FeIII FeIII NIII NIII NIII NIII NIII CrIV NIII NIII NIII FeIII CIII CIII CIII NIII TiIII FeIII FeIII CoIII MoIV TiIII CrIV FeIII NiIII FeIII AlIII AlIII FeIII CrIV ArIII FeIII VIV NiIII CaIII CrIV FeIII CaIII FeIII SIVCrIV FeIII CrIV NIII CaIII TiIII NIII NIII FeIII FeIII VIVMnIII NiIII FeIII FeIII FeIII FeIII CaIII NIII NIII FeIII FeIV FeIII MnIV FeIV FeIII CrIV FeIII FeIV CoIII FeIII CrIV TiIII VIV FeIII MnIV SIVCaIII NiIII FeIII VIV FeIII CrIV CaIII SIVCrIV VIV CrIV CrIV CaIII W a v e l e n g t h ( ˚ A ) − − Residuals
Fig. A.3 (continued): IUE spectrum of HZ 44 (gray) and the final model (red, with heavy metals: blue).
Article number, page 31 of 48 & A proofs: manuscript no. HZ44_HD127493 . . . . . . . . . NormalizedFlux
OIII KIII NII ArIII OIII NeII ArIII CaIII NeII NeII SIVNeII VIV NeII OIII NeII SIVNaII NaII NeII SIVArIV NeII KrIV OIII NeII NeII OIII NeII ArIII KrIV KIII VIV PbIV NaII NaII NeII NeII ArIII VIV NaII NaII KIII NeII OIII KIII NeII NeII ArIII FeIV NeII NeII NaII NaII SIVNeII NII ArIV VIV ArIII NaII NaII NaII NaII KrIV NII NeII NII NII NII SiIII SiIII NII NeII SIV SIVNaII NaII NeII SiIII SiIII NeII SiIII NeII SIV SIVMgII MgII NII ArIII VIV NIII VIV NIII NIII FeIV OIII NIII SIVNeII CaIII SIVVIVOIII NIII NII ArIII NaII NaII OIII NII OII NaII NaII KrIV NeII NaII NaII SiIV NII − − Residuals . . . . . . . . NormalizedFlux
NIII ArIII CaII NaII NaII NeII NeII NeII SiIV SiIV SIVNeII PVNeII NiIV CaII CaII TiIII SiIII SiIII NeII ArIII FeIV NeII NaII NaII NeII VIV SiIV SiIV NeII SiIII VIII NeII NII SiIV SiIV KIII SiIV SiIV VIII NII NeII KIII NeII SiIII CrIII NaII NaII NeII NeII SIVNeII SIVNIII PbIV NIII SIVNeII VIV NIII NeII NeII NeII FeIV NeII SiIII NII NeII NeII NeII CaIII FeIV FeIV SIII PIII SiIII SIII VIV FeIV SIVOIII VIV SiIV SiIII NeII SIVNeII SiIV TiIII SIII NeII NeII NeII ArIII NIII OIII NIII KIII NeII PIVNaII NaII NIII SiIII OIII NeII OIII OIII VIV NIII NeII NeII NIII VIV TiIII KIII OIII OIII VIV − − Residuals . . . . . . NormalizedFlux
NaII NaII ArIII KIII SIVVIV NeII VIVOIII SIV SIVArIII NIII NIII NIII SIV SIVNeII ArIII NeII OIII SIVNII NeII NeII GeIV KIII NeII SIII NII SIII NeII VIV NII NeII NIII NII NIII NII SIVTiIII NII TiIII NIII GeIV NeII VIV NeII SIVArIII TiIII SIVOIII SIVNIII NIII SIV SIVNeII ArIII SIVNeII NeII NeII TiIII SIVPIVOIII NIII NIII TiIII NeII SIVNIII NeII NeII KIII ArIII NIII NeII NIII ArIII NeII NeII NeII SIVKIII PIVNIII SIII NeII NIII CaIII SIII SIV SIII NIII PIVTiIII NeII CaIII NIII NeII NIII NIII NIII NeII NeII SIII NeII ArIII SIVNeII SIV SVNeII NeII NII SIVNeII − − Residuals . . . . . NormalizedFlux
NeII TiIII NeII KIII KIII ArIII PIVOIII SIVOIII NeII OIII SIVVIV NII ArIII NeII OIII NeII SVNIV NeII OIII NIII NIV OIII OIII VIV NIII OIII NIII VIV NeII NIV NeII OIII VIV NeII NeII NeII NeII VIV VIV NIV NIV NIII KIII OII OII ArIII VIV ArIII NIII VIV NIII NIII NIV VIV NeII NIV NeII ArIII NeII KIII NeII NIV NIII NIV NIII SiIII SiIII SiIII VIV VIV VIV VIV ArIII SIII SIVArIII ArIII SIII ArIII ArIII ArIII FIINeII ArIII KrIV FII CIII ArIII ArIII SiIV SiIV ArIII KIII ArIII VIV GaIII VIII NaII NaII FeIV CaIII NeII SIVMgII TiIV NeII NeII SIVNeII VIV NeII W a v e l e n g t h ( ˚ A ) − − Residuals
Fig. A.4: HIRES spectrum of HZ 44 (gray) and the final model (red).
Article number, page 32 of 48. Dorsch et al.: The chemical composition of HZ 44 and HD 127493 . . . . . NormalizedFlux
SIII VIV GeIV NeII NeII NIII ArIV FeIV FeIV ArIV NeII NIII NIII KrIV NeII VIV SIVNeII NIII NeII NIII NeII ZrIV TiIV GaIII SIV FeIV TiIV ArIV TiIV CaIV NeII SiIII SIVNII NeII FeIV AlIII AlIII FeIV CIII CIII CIII NII CIII CIII SIVNeII AlIII NIII NII NII NIII SIII NII NeII NaII NaII ZnIII SIII CrIII NeII NIII SIV FeIV ArIII NeII NeII ZrIV SIII ZrIV NeII SIII NeII NiIV FeIV ArIII TiIV TiIV GeIV SiIV SiIV FeIV SIII NeII − − Residuals . . . . . NormalizedFlux
NiIV TiIV TiIV ZrIV SiIV SiIV ArIII SiIV SiIV CaIII VIV ArIII NeII OIII ArIII NeII OIII NeII AlIII OIII CIII OIII OIII VIV CaII OIII SIII ZrIV NeII SIII OIII OII ArIII NeII AlIII NiIV OIII OIII ArIII SIII ArIII SiIV OIII NeII NIII OIII NIII NeII NeII OII SIVOIII OIII OIII GaIV NeII CaII SIVOII NeII CaIII NeII NIII NIV SIII OII ZrIV SIII NeII NIII NeII NIII OIII ArIII OIII NIII NIII OIII CaIII SiIV SiIV OII NIII NeII ZrIV NiIV NeII NIII NIII NIII SiIV OIII SIII NeII NiIII SIII NIII CaIV NeIII NIII NiIII NIII SIVOIII SiIII NIII NiIV SIII ArIII SiIII SiIII NiIII NeII ArIII NiIV SiIII GaIII SiIII SiIII SrIV − − Residuals . . . . . . . NormalizedFlux C a II NiIII SIVNiIII NeII NiIII NeII CaIII NiIII NiIII NeII NII SIII VIV SIII SIII NII NiIII NeII OIII NII NiIII FIINII OIII FII FIINiIII NII NII ArIII KrIV SnIV SIVNiIII OIII NiIII TiIII OIII ArIII SiIV VIV KrIV TiIII NiIII OII CIII CIII NiIII CIII NII CIII SIV FeIV NII TiIII NiIII TiIII SIVNiIII CaIV NII FII SIII NiIII NiIII ArIII SrIV NiIII SrIV OII NII SrIV TiIII NII TiIII NII NiIII CII NII OII NII SiIV NeIII NeIII NeIII NeIII TiIII TiIII TiIII SiIII NII SiIV SiIV SIII SiIV SiIV CaIII CaII CaII CaII CaII CaII CaII CaII CaII CaII CaII CaII NiIII NIII OIII ArIII NIII NiIII NII NII NII NiIII NIII NiIII − − Residuals . . . . . . . NormalizedFlux C a II OII NII NiIII NII OIII NiIII CaIII NiIII NiIII FeIII OII NII NiIII ArIII SIII OIII PbIV FeIII NiIII MnIV TiIV TiIV CaII CaII CaII CaII CaII CaII CaII CaII CaII FeIII SIV FeIII FeIII NiIII OII PIII PIII FeIII NiIII OII SIII NiIII SIII NiIII NII ArIII NIII SIII NIII ArIII NiIII NIII NIII FeIV FeIII NIII FeIV NIII NIII ArIII NII FII FeIII FIINiIII FIINiIII NII SiIV OII NII NII SiIV CaIII NII YIII YIII NII NII NII NIII NIII PbIV FeIII CIII NII NIV PIII CIII ArIII OII OII OII NeII FeIV MoV CIII CIII CIII CIII OII OII CIII CIII OII CaIII OII NII OIII W a v e l e n g t h ( ˚ A ) − − Residuals
Fig. A.4 (continued): HIRES spectrum of HZ 44 (gray) and the final model (red).
Article number, page 33 of 48 & A proofs: manuscript no. HZ44_HD127493 . . . . . . . . NormalizedFlux
OII NII OIII CaIII NII NII OII OII OII NII SiIV ArIII OII SIII OII OII NII OII OII NIII NII ArIII OII NeII SIII NeII SiIII SiIII SiIII SiIII SiIII OII FIINIII FIIOII OII OII NII NII SiIV OII OII FeIII FeIII CIII FeIII NII TiIV NIII NII NIII NIII OII NII NeII TiIV TiIV NIII CaIII NIII CaIII FeIII FeIII NIII NIII NIII FeIII NII OII NIII ArIII NIII AlIII AlIII NeII NIII CIII OII CaIII NIII NII NII CIII NII NII NII CIII CaIII CaIII FeIII NII SIVNII NII FeIII PbIV CaIII NII NII NII NIII NIII NIII ArIII CaIII OII CIII CIII OII NIII NII ZrIV ArIII NII TiIII NIII NII CaIII TiIII − − Residuals . . . . . . NormalizedFlux
CaIII TiIII CaIII SiIV SiIV SiIV CaIII TiIII TiIII NIII NeII SiIV NeII NeII NeII PIII NeIII SiIV SiIV NII CaIII SiIV SiIV SIVNeIII NeII NeII CaIII NeII NIII NII NII NeII NII NeII CaIII NII NII NII NII TiIII NII TiIII PIVNeII SIII OII OII CaIII NeII NeII NeII SIVCII CII SIVTiIII CaIII CaIII OII OII CaIII CaIII CaIII SIII TiIII TiIII CaIII TiIII NeII NeII OII SIVOII CaIII TiIII FeIII CaIII SIVCaIII CaIII NIII OII TiIII FeIII NIII FeIII SiIV OIII ZrIV OII NIII CaIII OII NaII NIII NIII NeII NeII NeII NIII OII NIII NIII SiIV CaIII NiIII OII SIII OII NIII TiIII CaIII NiIII NiIII NiIII OII NIII NiIII SiIII − − Residuals . . . . . . NormalizedFlux
NeII SIII OII CaIII NeII NiIII OII NiIII NiIII CaIII OII NIII NeII NiIII OII TiIII OII NIII NiIII OII TiIV NiIII NiIII OII NiIII SIII NiIII CaIII SIVNiIII SIII NiIII NiIII SIII NiIII NeII OII OIII CIII OIII NeII FeIII FeIII OIII NeII TiIII NIII NIII NIII NeII OIII CaIII NeII MgII NeII MgII NeII NaII TiIV NeII CaIII TiIV SiIV SiIV NaII CaIII OIII NeII NeII NeII OIII OII NeII OII NII NIII NeII NII NII NeII NeII NeII NeII NeII NeII NeII CaIII NeII NII NeII NII NII TiIII OIII NeII NeII SIII NeII NII NeII NIII ArIV SIVNeII NaII NII OIII ArIII NeIII OIII NaII NeII SIVNeII NeII OIII NeIII NII NeII OII − − Residuals . . . . . . . NormalizedFlux
NeII OIII NII OII SIII NaII NIII NIII CaIII AlIII AlIII TiIII AlIII MgII MgII MgII NaII OIII CaIII CaIII SIV SIVNaII OII PbIV NeII NeII CaIII SiIV SiIV SIVCaIII NII NeII NII NIII NIII NeII NeII AlIII CaIII NIII NeII CIII SrIV CaIII CIII NeII NeII NeII NIII VIV NII NaII NeII NIII NIII TiIV ArIV NIII NIII AlIII AlIII SIVNII NIII TiIII NaII NIII NeII NIII NeII PbIV PbIV SIVNIII PIVTiIII PIV PIV PIVNIII NIII NIII ArIII NIII NIII PIVNIII NIII TiIII NIII NII SiIII NeII CaIII NeII NII NII ArIII SiIII NeII ZrIV ZrIV SIVCaIII SrIV SrIV SiIII NeII NeII NIII OII NIII CIII OII SIVNII NII OII W a v e l e n g t h ( ˚ A ) − − Residuals
Fig. A.4 (continued): HIRES spectrum of HZ 44 (gray) and the final model (red).
Article number, page 34 of 48. Dorsch et al.: The chemical composition of HZ 44 and HD 127493 . . . . . . NormalizedFlux
NII NIII NIII NIV NII NII OII OII NIII NIII NII NIII NIII NIII NeII NIII NIII TiIV TiIV NIII NII NIII NIII NIII NeII NIII NIII NIII NII SiIV SiIV SiIV CaIII NIII TiIII NeII NIII OII NIII OII NIII NIII NII VIV NIII CIII OII CIII OII CIII CIII CIII TiIII SiIV SiIV SiIV NII TiIV TiIV TiIV SIVOII CIII CIII SiIV SiIV NII SiIV SiIV SIVCIII NII OII SiIV SiIV TiIV TiIV SIII NII NIII SiIV SiIV SiIII SiIII SiIV SiIV NeII SiIV SiIV VIII ArIII SiIV SiIV SiIV SiIV NIII ArIII NII NII NII OII OII NII NII OII NII OII NII ArIII CaIII NII OII NII VIII CaIII SiIII NII NII SIVArIII − − Residuals . . . . . . . NormalizedFlux
CaIII NIII NIII MgII MgII NIII NIII NIII NIII CaIII NIII NIII NIII NIII NIII ArIII ArIII NII NII NII NII NII NII TiIV NII NIII SiIII SiIV SiIV VIV SIII NII NIV NII SiIII SiIII SiIII CaIII SiIII SiIII VIVOII ArIII ArIII TiIII MgII MgII CaIII CaIII NIII VIVOII OII TiIII NIII NIII CaIII NII CIII NII CIII OII NIII GaIII − − Residuals . . . . . . . NormalizedFlux
NIII NIII NIII NIII OII NIII NIII TiIII CaIII NIII SIVNIII NIII CaIII CaIII OII ArIII NII NIII NIII NIII CaIII VIV AlIII AlIII NIII SVVIVOII NIII NIII NIII VIV TiIII SIVVIV CaIII CaIII NiIII OII KIII FeIV TiIII VIV TiIII CaIII TiIII SIVCaIII OII OII TiIII TiIII NII TiIII SiIV SiIV SiIV CaIII CaIII VIV SIVNII NIII CaIII CaIII VIV CaIII NII VIV TiIII CaIII NII GeIV NII VIV NII NII SIVArIII GaIII NII NII NII NII NII − − Residuals . . . . . . NormalizedFlux
NII NII CaII NII NII NII NII CaIII NII CaIII CaIII NII NII NII CaIII CaIII NIII NII PIV CaIII CaII NIII NIII NII NII FeIV VIV NII VIV NII NII CaIII CaIII NIII NIII NIII CaIII VIV CaIII NIII NIII NiIII GeIV NII VIV ZnIII NiIII CaIII CaIII TiIII CaIII SiIII SiIII SiIII SiIII NII NiIII NII NeII NII NIII CaIII SiIII SiIII SiIII CaIII W a v e l e n g t h ( ˚ A ) − − Residuals
Fig. A.4 (continued): HIRES spectrum of HZ 44 (gray) and the final model (red).
Article number, page 35 of 48 & A proofs: manuscript no. HZ44_HD127493 . . . . . . . . NormalizedFlux
CIII VIV CIII CIII CIII NII NIII NIII NIII CaIII CaIII NII VIV TiIII NIII NIII NIII NiIII AlIII AlIII OII SIII AlIII AlIII NII NII NII NII NII NII NiIII NiIII NII NII NII NIII NIII NII VIV NII NII NeII NII NII NII NII NII NII NII NiIII NeII NII NiIII NiIII NII TiIII VIII SiIII NeII NIV CaIII NeII NIII NIII NiIII NIV NiIII NiIII NIII NIII NIII OII NeII NeII SIII SiIV SiIV VIV SIVVIV NiIII CaIII NeII PIV FeIII NiIII NiIII PIV FeIII NiIII NiIII NII CaIII NIII CIII NiIII CIII NiIII NiIII NII NIII − − Residuals . . . . . . . . NormalizedFlux
VIV NIII MgII MgII VIVOIII NIII NIII CaIII CaIII NIII NIII CaIII CIII NIII FeIII VIV FeIII TiIII TiIII NiIII NiIII FeIII NIII FeIII NiIII NiIII TiIII CaIII NIII FeIII NIII FeIII TiIII CaIII FeIII CIII CIII SiIV CIII NII TiIII SiIV CaIII FeIII VIV NiIII NII NIII NII CaIII NII NIII NII CaIII NIII CaIII CaIII NIII NII CaIII NiIII CaIII SIVGaIII NII NII NIII NiIII NiIII CaIII NiIII NII VIV NiIII NIII VIV CaIII GaIII NII SIII NiIII CaIII FeIII NeII NiIII NeII NiIII NeII NeII NII NeII NeII NIII NeII NeII − − Residuals . . . . . . . . NormalizedFlux
NiIII NeII NeII NeII TiIV SiIV SiIVMgII MgII VIV NeII NeII NiIII SiIV SiIV NiIII SiIV SiIV SiIV SiIV NiIII NeII NeII NiIII NiIII NiIII NIII NIII NeII NiIII NiIII NiIII NiIII VIV NiIII NiIII SiIII NiIII NiIII SiIII NII NiIII SiIV SiIV NII CaIII ZrIV NII CaIII NiIII SiIV SiIV SiIV SiIV SiIV SiIV TiIV NiIII NiIII SiIII NiIII NII NII CaIII NII NiIII TiIV NiIII SIVNIII TiIV NiIII NII NiIII SIVCaIII ArIII NiIII NiIII NiIII OIII VIV NiIII TiIV NiIII NiIII CaIII NiIII − − Residuals . . . . . . . . . . NormalizedFlux
NII NiIII NiIII NiIII NiIII NiIII NII NiIII NiIII TiIII NiIII NII NII NII NiIII SIVNiIII NiIII NiIII NII NiIII NII NII NII NiIII NiIII NiIII CaIII NiIII NiIII CaIII NiIII NiIII NiIII NiIII OIII OIII NiIII VIV CaIII NII NiIII NiIII NIII CaIII W a v e l e n g t h ( ˚ A ) − − Residuals
Fig. A.4 (continued): HIRES spectrum of HZ 44 (gray) and the final model (red).
Article number, page 36 of 48. Dorsch et al.: The chemical composition of HZ 44 and HD 127493 . . . . . NormalizedFlux
CaIII NII SiIV ArIII NII NII NII NIII NIII NiIII NiIII CaIII CIII NiIII SiIII AlIII SIV SiIII NiIII VIV NII SIVNIII SiIII ArIII AlIII CrIV NII SiIII NiIII FeIII NII FeIII NII CIII SrIV ZrIV NiIII − − Residuals . . . . . . . NormalizedFlux N a I N a I CIV SiIV CIVNIII NIII FeIII NIII CIII NiIII FeIII FeIII GaIII NIII CaIII FeIII FeIII SiIV SiIV FeIII SIV FeIII SiIV SiIV FeIII SiIV SiIV SiIV SiIV FeIII TiIV NiIII TiIV TiIV CII TiIV FeIII NII NII CIII NII NII FeIII SiIII NII NIII NIII NII NII NII NII CaIII − − Residuals . . . . . NormalizedFlux
FeIII FeIII FeIII NII NII FeIII NII FeIII FeIII VIV NII CrIV NIII NIII NII NII NII NII NII FeIII NII NII NIII FeIII NII NIII FeIII NII TiIV NII NII NII ArIII FeIII SrIV FeIII FeIII FeIII NII FeIII FeIII FeIII GaIII FeIII FeIII FeIII FeIII FeIII FeIII NII FeIII CaIII FeIII − − Residuals . . . . . . . . NormalizedFlux
FeIII FeIII FeIII NII CaIII NiIII NII NII NIII NII NII NIII NIII NeII NII NII CaIII NeII NeIII CaIII NII CaIII SIVNeIII FeIII NII NII FeIII CaIII NII NeII NeII NII FeIII NeII NII FeIII FeIII SiIII NII CaIII NII NII FeIII GeIV W a v e l e n g t h ( ˚ A ) − − Residuals
Fig. A.4 (continued): HIRES spectrum of HZ 44 (gray) and the final model (red).
Article number, page 37 of 48 & A proofs: manuscript no. HZ44_HD127493 . . . . . NormalizedFlux
ArIII FeIII CaIII FeIII GeIV NiIII CaIII NeII CaIII CaIII MnIII TiIV SIVNeII NII NII TiIV TiIV NeII NeII SIVNeII NII NII NII NII NeII NeII NII NII CaIII NII TiIV GeIV CaIII NeII NeII NeII NeII VIII SiIV SiIV SiIII − − Residuals . . . . . . . . . NormalizedFlux
SiIV NeII SIV SrIV NII SiIV NII NII NII NeII MgII NIIMgII NeII NII NII NIII CaIII CaIII NII NIV NII CaIII NIII NII NeI NII SIII GeIV CaIII CaIII CaIII NII NII SIVNIII − − Residuals . . . . . . NormalizedFlux
NIII NIII SIVCaII CaII NIII NIII NIII NIII NIII SiIII SiIII SiIII SiIII SiIII SIVNIII NII CaIII NIII NII OII NII NII OII NII NII NIII NIII OII OII NeII NeII NeII NeII CIII NIII NII NeII NeII SiIII NII SiIII SIV SiIII SIVNeII NeII NIII NIII NII NeII NeII SIV SiIII SiIII SiIII NeII CaIII NeII NeII NeII CaIII SiIV SiIV NII NIIMgII MgII SIVOII NeII NeII SIV SIVNII OII AlIII AlIII SiIV SiIV SiIV SiIV AlIII NeII SiIV SiIV OII NeII NII NII VIII NII OII OII NeII NeII VIII CII − − Residuals . . . . . . . . NormalizedFlux
ArIII CaIII NII CII SIVNII VIII NII CaIII NII NII NII TiIII NII NII SIVOII TiIII SiIV SiIV SiIV TiIII TiIV TiIII CaIII NeI TiIV SIV SiIV SiIV W a v e l e n g t h ( ˚ A ) − − Residuals
Fig. A.4 (continued): HIRES spectrum of HZ 44 (gray) and the final model (red).
Article number, page 38 of 48. Dorsch et al.: The chemical composition of HZ 44 and HD 127493 . . . . . . NormalizedFlux S II S II S II S i II ZnIV ZnIV NiV CrIV NIV SbV SeV SIVGaIV ZnIV FeIV FeIV GeIV SiIV NiVNiVNiVNiVNiVNiV PbV NiVNiVNiV FeV NiIV SiIII FeIV NiV CrIV NiVNiVNiVNVFeIV ZnIV NiVNiVNiVNiVNiVNiVNiVNVNiVNiVNiVNiV SrIV NiVNIII SrIV NiVNiVNiVNiV GaIV NiIV FeIV NiV CrIV CIII NiV FeIV PbV NiVNiV ZnIV NiV CrIV NiVNiV FeV CrIV FeIV SIVNiVNiVNiV FeIV NiVNiVNiIV NiVNiV CrIV FeIV ZnIV FeIV NiVNiVNiVNiIV FeIV CrIV CrIV NiIV FeIV CrIV NiV CrIV NiV FeIV SIVNiV GaIV CrIV NiVNiIV FeIV NiVNiV CrV CrIV FeIV NiVNiVNiV SIVNiV CrIV CrIV FeIV NiV CrV NiIV NiIV NiV FeIV NiVNiV ZnIV NiV SVFeV − − Residuals . . . . . . NormalizedFlux C I O I S i II NiVNiV ZnIV CrIV NiV SVNiIV NiIV NiIV NiIV NIV FeV NiV FeIV NIV ZnIV NIV ZnIV CrIV NiVNIV NIV NiV SVNiVNiV ZnIV SiIV SiIV NiV FeV NiVNiV FeV ZnIV FeIV TeV NiV ZnIV NiIV ZnIV NiIV FeV ZnIV NiV ZnIV CrIV CrIV SIV SIV FeV CrIV NIII FeV CrIV NIII NIII CrIV CrIV ZnIV NIII FeV ZnIV CrIV ZnIV FeV FeV SiIII NiVNeIII NiIV SIVGaIV SIVCrIV NiIV NIV ZnIV SIV SiIII ZnIV CrIV NiIV FeV CrIV NiV SiIII SiIII FeIV AsIV GaIV CrIV NiIV NiIV FeIV CrIV FeV CrIV NiV SiIII ZnIV NiIV NiIV SiIII FeV FeV GaIV CrIV NiV CrIV NiV CrIV FeV ZnIV NiIV NiVNiV ZnIV CrIV CrIV CrIV FeV NiV CrIV CrIV CrIV FeIV NiV CrIV NiIV FeV NIV CrIV NiVNiIV − − Residuals . . . . . . NormalizedFlux C II C II C II NiV CrIV NiIV FeV NiIV NIII PbIV NiVNiIV NIII SnIV NiIV NiIV NiIV CrIV NIII NIII NIII NiV FeV ZnIV FeV NiIV NIII NiVNiIV NiIV CrIV CrIV FeV ZnIV NiIV FeIV ZnIV FeV FeV ZnIV ZnIV NiIV FeV NIII CrIV NiVNIII NIII NIII NIII NiIV CrIV CrIV ZnIV NiIV CrIV NiIV NiIV FeIV ZnIV NiV CrIV FeIV ZnIV ZnIV FeV SrIV FeV CrIV CrIV CrIV NiIV CrIV ZnIV ZnIV CrIV CrIV NiIV FeIV NiV CrIV FeIV NiIV NiIV NiIV CrIV GaIV OIV NiIV NiIV CrIV CrIV NiIV FeV CrIV ZnIV CrIV CrIV NiV ZnIV OIV ZnIV NiIV ZnIV NIII FeV NiIV NIII NiIV NIII NIII CrIV NiIV CrIV CrIV ZnIV NiIV CrIV CrIV SiIV NiIV ZnIV NiIV NiIV NiIV FeV CrIV CrIV NiIV SVNiIV CrIV NiIV CrIV FeV ZnIV CrIV FeV − − Residuals . . . . . . NormalizedFlux N i II NiIV FeV CrIV NiIV ZnIV ZnIV NiIV NiIV FeIV FeV ZnIV FeV FeV NiIV FeIV FeV NiIV ZnIV NiIV FeV FeV FeV CrIV FeV FeV SIV FeV FeV NiIV ZnIV FeV CrIV ZnIV NiIV FeIV FeV FeV FeV NiIV ZnIV NiIV FeV PIVNiIV CrIV CrIV NiIV ZnIV FeV NiIV NiIV FeIV NiIV NiIV NiIV FeV PIV CrIV CrIV FeV FeV NiIV FeV FeV FeV FeV ZnIV CrIV CrIV FeV FeV CrIV ZnIV NiIV CrIV NiIV FeV NiIV FeV FeV CrIV NiIV FeIV NiIV NiIV NiIV CrIV NiIV FeV AlIII NiIV NiIV FeIV FeV FeV FeV NiIV NiIV NiIV NiIV CrIV NiIV NiIV FeV NiIV NIII NIII NIII ZnIV FeV NIII FeV FeIV FeV NIII NiIV FeV NiIV NiIV FeV SiIV FeV FeV FeIV NiIV NiIV NiIV NiIV FeIV NiIV NiIV NiIV NiIV FeV NiIV W a v e l e n g t h ( ˚ A ) − − Residuals
Fig. A.5: GHRS spectrum of HD 127493 (gray) and the final model (red, with heavy metals: blue).
Article number, page 39 of 48 & A proofs: manuscript no. HZ44_HD127493 . . . . . . NormalizedFlux
FeIV NiIV NiIV NiIV NiIV FeV NiIV NiIV NiIV NiIV NiIV CrIV CrIV NiIV FeV NiIV FeV NiIV NiIV CrIV SiIV CrIV FeIV NiIV FeV FeV FeV NiIV FeIV FeV NiIV FeV FeV ArIV FeV FeV NiIV NiIV NIII NIII NiIV NiIV FeIV NiIV FeV NiIV FeIV NiIV NiIV NiIV FeV FeV NiIV NiIV NiIV SiIII NiIV CrIV FeV NiIV NiIV NiIV FeV NiIV NiIV NiIV ArIV NiIV NiIV FeIV FeV NiIV NiIV FeIV FeIV NiIV FeIV FeIV NiIV FeIV NiIV FeIV FeIV NiIV FeIV FeIV NiIV FeIV FeIV NiIV FeIV FeIV FeIV NiIV FeV FeV NiIV NiIV NiIV FeIV FeV NiIV NiIV FeIV NiIV NiIV NiIV CrIV NiIV FeIV NiIV NiIV NiIV NiIV NiIV NiIV NiIV NiIV NiIV NiIV NiIV NiIV NiIV NiIV NiIV CrIV NiIV FeIV NiIV FeV NiIV FeV FeIV FeV NiIV − − Residuals . . . . . . NormalizedFlux
NiIV NiIV NiIV FeV NiIV NiIV NiIV NiIV FeIV FeIV NiIV NiIV NiIV NiIV NiIV NiIV FeIV FeV NiIV NiIV FeIV FeV NiIV FeV NiIV NiIV NiIV NiIV TiIV NiIV NiIV FeIV FeIV NIII FeIV NiIV FeV NiIV NiIV NiIV FeIV FeV NiIV FeV NiIV NiIV FeV NiIV FeIV FeIV NiIV NiIV NiIV FeIV FeIV NiIV FeIV FeV FeV FeIV NiIV NiIV FeV FeIV NiIV NiIV NiIV NiIV NiIV NiIV NiIV FeIV FeV NiIV FeV FeIV FeV FeV CrV NiIV FeV FeIV FeIV NiIV FeIV NiIV TiIV NiIV NiIV FeV NiIV FeV TiIV NiIV FeIV FeIV NiIV FeIV NIII NIII NIII NIII FeV FeV NiIV NiIV FeIV FeIV NiIV NiIV NiIV NiIV NiIV NiIV NiIV NiIV NiIV NiIV NiIV NiIV NiIV FeV NiIV NiIV FeIV NiIV NiIV NiIV FeIV FeIV NiIV NiIV NiIV PIVNiIV − − Residuals . . . . . . NormalizedFlux C I NiIV FeIV FeIV FeIV FeIV FeIV FeIV NiIV FeIV FeIV FeIV FeIV FeIV SiIV SiIV FeIV FeIV FeIV FeIV FeIV CoIV NiIV NiIV FeIV NiIV FeIV FeIV FeIV NiIV NiIV NiIV FeIV FeIV NiIV FeIV FeIV FeIV FeIV NiIV NiIV FeIV NiIV NiIV NiIV NiIV NiIV FeIV FeIV FeIV CaIII NiIV FeIV NiIV FeIV FeIV FeIV NiIV CIVNiIV FeIV NiIV NiIV FeIII NiIV CIV FeV FeIV FeIV FeIV FeIV FeIV FeIV FeIV NiIV NiIV FeV FeIV NiIV FeIV FeIV FeIV NiIV FeIV NiIV FeIV NiIV FeIV FeIV FeIV FeIV FeIV NiIV NiIV NiIV FeIV FeIV NiIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV NiIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV NiIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV NiIV FeIV FeIV FeIV FeIV W a v e l e n g t h ( ˚ A ) − − Residuals
Fig. A.5 (continued): GHRS spectrum of HD 127493 (gray) and the final model (red, with heavy metals: blue).
Article number, page 40 of 48. Dorsch et al.: The chemical composition of HZ 44 and HD 127493 . . . . . . NormalizedFlux C I FeIV FeIV FeIV FeIV FeIV FeIV NiIV FeIV FeIV CoIV FeIV FeIV NiIV FeV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV SIV SIV FeIV NiIV CoIV FeIV FeIV FeV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV SIV FeIV NiIV FeIV FeIV FeIV FeIV FeIV NiIV FeIV FeIV FeIV FeIV FeIV FeIV CoIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV NiIV SiIV SiIV FeIV FeIV NiIV FeIV FeIV FeIV FeIV FeIV CrV CrV FeIV NiIV FeIV FeIV FeIV NiIV FeIV FeIV CoIV FeIV FeIV FeIV CrV FeIV FeIV NiIV FeIV FeIV FeIV FeIV NiIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV NiIV CrV NiIII FeIV FeIV FeIV FeIV FeIV CrV FeIV NiIII FeIV FeIV FeIV FeIV FeIV FeIV FeIV NiIV CrIV FeIV FeIV FeIV FeIV − − Residuals . . . . . . NormalizedFlux N i II FeIV FeIV FeIV CrIV FeIV FeIV FeIV CrV FeIV FeIV FeIV FeIV NiIII NiIII FeIV NiIII FeIV FeIV FeIV NiIII FeIII FeIV FeIV NiIV FeIV FeIV NiIV CrIV FeIV NiIII FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV NiIII FeIV CrIV NIV FeIV NiIII FeIV CrIV FeIV FeIV MnIV MoV FeIV FeIV NiIII SiIV SiIV FeIV CrIV MnIV FeIV NiIV FeIV NiIII FeIV FeIV FeIV NiIV FeIV NiIII FeIV MnIV CrIV NIII FeIV FeIV FeIV FeIV FeIV FeIV CrIV SiIV FeIV FeIV FeIV FeIV NIII NIII NIII NIII FeIV NiIV NIII FeIV CrIV SVNIII CrIV NIII FeIV FeIV FeIV NiIII CrIV FeIV CrIV CrIV FeIV FeIV NiIV FeIV NiIV NiIII FeIV FeIV NiIII NiIII SIV FeIV CrIV FeIV FeIV FeIV FeIV CrIV CrIV FeIV FeIV NiIII MnIV FeIV FeIV CrIV FeIV FeIV SIVCrIV W a v e l e n g t h ( ˚ A ) − − Residuals
Fig. A.5 (continued): GHRS spectrum of HD 127493 (gray) and the final model (red, with heavy metals: blue).
Article number, page 41 of 48 & A proofs: manuscript no. HZ44_HD127493 . . . . . . . NormalizedFlux F e II O I C I S I S I C I C I C I C I S I S I N I S I N I S I S II N I N I S i II S i II N I N I N I S i III D I H I H I H I S II S II OIII FeIV PbV CrIV NIV CIV CIVNIV NIV NIV FeIV CIII CIII CIII CIII CIII CIII FeIV FeIV NIII NIII TiIV ZrIV FeIV NIII NIII PbV NIV GeIV PbV NiIV FeIV CrV TiIV NIV NIV NIV FeV FeV CrIV SVSIII CrIV ZrIV FeV NiIV FeIV SiIII SiIII CrIV SiIII CrIV CrIV SiIII SiIV CrIV PbV FeIV CrIV CrIV CrIV ArV ZrIV CrIV FeIV CrIV CrIV ZnIV ZnIV NIV SbV SeV SIVZnIV FeIV GeIV SiIV PbV FeV NiIV NiV NiV NVNiV NVNiV NIII NiV NiIV FeIV CrIV CIII FeIV NiV CrIV NiV CrIV FeIV SIVNiV NiV FeIV NiV NiIV NiV CrIV FeIV FeIV NiV − − Residuals . . . . . . . NormalizedFlux S II S i II C I O I S i II C II C II C II SIVGaIV NiV ZnIV NIV NIV NIV TeV SIV SIVCrIV CrIV NIII NIII CrIV CrIV SiIII SIVNIV SIV SiIII SiIII SiIII AsIV CrIV SiIII SiIII CrIV CrIV ZnIV CrIV NIV CrIV NiIV PbIV NIII NiIV CrIV NIII NIII NIII ZnIV NiIV NIII NiIV CrIV FeV ZnIV FeIV ZnIV ZnIV NiIV FeV NIII NIII NIII NIII NiIV CrIV NiIV CrIV CrIV FeIV FeV SrIV CrIV CrIV NiIV CrIV CrIV FeIV CrIV NiIV NiIV CrIV OIV NiIV NiIV CrIV CrIV NiIV CrIV CrIV OIV NiIV ZnIV NIII NiIV NIII NiIV NIII CrIV ZnIV CrIV SiIV ZnIV NiIV NiIV CrIV CrIV NiIV CrIV CrIV CrIV NiIV ZnIV NiIV FeIV ZnIV − − Residuals . . . . . . NormalizedFlux N i II NiIV NiIV NiIV FeV FeV NiIV NIII NIII NIII NIII SiIV NiIV NiIV NiIV NiIV NiIV NiIV SiIV FeV NiIV FeV FeV NiIV NIII NiIV NiIV NiIV NiIV NiIV SiIII NiIV NiIV NiIV NiIV NiIV NiIV FeIV FeIV FeIV FeIV NiIV FeIV FeIV NiIV FeIV FeIV NiIV NiIV NiIV FeIV FeV NiIV NiIV FeIV NiIV NiIV FeIV NiIV NiIV NiIV NiIV NiIV NiIV NiIV NiIV NiIV FeV FeIV NiIV NiIV NiIV NiIV NiIV FeIV NiIV NiIV NiIV NiIV FeIV NiIV NiIV FeV NiIV NiIV NiIV TiIV NiIV NiIV FeIV FeIV NiIV NiIV FeIV NiIV FeV NiIV FeV NiIV FeIV FeIV NiIV FeIV NiIV FeIV FeV FeIV NiIV NiIV NiIV − − Residuals . . . . . . NormalizedFlux S i II C I TiIV NiIV NIII NIII NiIV FeIV NiIV NiIV NiIV FeIV PIV FeIV NIV NiIV FeIV NiIV NiIV FeIV NiIV FeIV NIII NIII NiIV NiIV NiIV FeIV SVFeIV FeIV FeIV NiIV NiIV NiIV NiIV NiIV FeIV NiIV FeIV NiIV NiIV FeIV FeIV NiIV NiIV NiIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV NiIV NiIV FeIV NiIV FeIV NiIV FeIV FeIV FeIV NiIV NiIV NiIV FeIV NiIV NiIV FeIV NiIV CIVNiIV FeIV CIV FeIV FeIV FeIV FeIV FeIV NiIV FeIV FeIV FeIV FeIV NiIV FeIV NiIV FeIV NiIV NiIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV W a v e l e n g t h ( ˚ A ) − − Residuals
Fig. A.6: IUE spectrum of HD 127493 (gray) and the final model (red, with heavy metals: blue).
Article number, page 42 of 48. Dorsch et al.: The chemical composition of HZ 44 and HD 127493 . . . . . . NormalizedFlux F e II C I FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV NIII FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV AlIII FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV AlIII FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV SIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV SIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV CrIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV − − Residuals . . . . . . NormalizedFlux A l II N i II FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV CrIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV SIV FeIV FeIV FeIV CrIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV NIII NIII FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV NIV FeIV FeIV FeIV SiIV SiIV FeIV FeIV FeIV FeIV FeIV FeIV CrIV SiIV FeIV FeIV NIII NIII NIII NIII FeIV FeIV NIII CrIV FeIV FeIV CrIV FeIV FeIV CrIV FeIV CrIV FeIV FeIV FeIV CrIV CrIV NIII NIII NIII FeIV FeIV FeIV CrIV CrIV CrIV CrIV FeIV CrIV FeIV CrIV − − Residuals . . . . . . NormalizedFlux S i II CrIV FeIV CrIV FeIV CrIV CrIV CrIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV CrIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV FeIV CrIV FeIV CrIV FeIV NIII NIII FeIV FeIV NIII CrIV NIII FeIV CrIV CrIV FeIV FeIV CrIV FeIV FeIV CrIV FeIV CrIV FeIV FeIV CrIV FeIV FeIV CrIV CrIV CrIV FeIV CrIV CrIV CrIV FeIV CrIV FeIV CrIV FeIV CrIV FeIV CrIV CrV CrIV CrIV FeIV FeIV CrIV CrIV FeIV CrIV NIII NIII NIII NIII NIII NIII NIII NIII CrIV FeIV CrIV FeIV FeIV NiIII AlIII CrIV FeIV FeIV FeIV CrIV AlIII CrIV CrIV CrIV CrIV FeIV FeIV FeIV CrIV CrIV FeIV FeIV FeIV − − Residuals . . . . . . NormalizedFlux
FeIV CrIV FeIV FeIII FeIV FeIV FeIV FeIV CrIV FeIV FeIV NIII FeIII NIII NIII FeIII FeIV PIV FeIV FeIII FeIV FeIII FeIII FeIII FeIV FeIV FeIII CrIV CrIV NIII FeIII NIII NIII FeIV NIII FeIV CrIV FeIII SIV FeIII FeIII SIV FeIII NIII NIII NIII CrIV NIII NIII NIII FeIII FeIV NIII FeIII FeIV FeIV CrIV FeIII FeIII FeIV AlIII FeIII CrIV FeIII VIV CrIV FeIV FeIII FeIII SIVCrIV FeIII CrIV NIII NIII NIII FeIII FeIII FeIII FeIV FeIII FeIII FeIII NIII NIII FeIII FeIV FeIV FeIII FeIV FeIV FeIII CrIV FeIII FeIV FeIII FeIV CrIV FeIV FeIII SIV FeIV FeIII CrIV CrIV CrIV FeIV FeIV FeIV W a v e l e n g t h ( ˚ A ) − − Residuals
Fig. A.6 (continued): IUE spectrum of HD 127493 (gray) and the final model (red, with heavy metals: blue).
Article number, page 43 of 48 & A proofs: manuscript no. HZ44_HD127493 . . . . . . . NormalizedFlux
NIII NIII NeII SIVNeII NeII NIII NIV NeII NIII NeII NIII OIII OIII NIII OIII CaIII SiIV SiIV NIII ZrIV NeII NIII NIII SiIV OIII NeII NIII NeIII NeIII NIII SIVOIII SiIII NIII NiIV ArIII SiIII SiIII NeII SiIII SiIII SIVNeII NeII NII NII NeII NII FeIV NII NII NII ArIII SIV − − Residuals . . . . . . . NormalizedFlux C a II C a II SiIV CIII CIII FeIV SIVCaIV NiIII SrIV NII NII SiIV NeIII NeIII NeIII NeIII SiIII SiIV SiIV SiIV SiIV CaII CaII CaII CaII CaII CaII CaII CaII CaII CaII CaII NIII NIII NII NII NII NIII FeIII NII ArIII OIII NeIII PbIV NiIII FeIII FeIII NII NIII NIII NIII FeIV NIII FeIV NIII NIII − − Residuals . . . . . . . . NormalizedFlux
ArIII NII SiIV NII SiIV YIII YIII NII NII NII NIII NII NIV FeIV CIII CIII CIII NII NII NII SiIV ArIII FeIV NII NIII NII NeII NIII SiIV FeIII TiIV NIII NII NII NeII TiIV TiIV NIII CaIII NIII FeIII NIII NIII NIII NII NIII NIII AlIII AlIII NeII NIII NIII NII CaIII FeIII − − Residuals . . . . . NormalizedFlux
SIVNII NII NII NIII NIII ArIII CaIII CIII NIII NII ZrIV NII NIII CaIII SiIV SiIV SiIV NIII NeII NeII NeII NeIII NII CaIII NeIII NeII NeII CaIII NeII NII NII NeII CaIII NII NII PIVNeII SIV SIVCaIII CaIII CaIII CaIII NeII NeII CaIII CaIII NIII FeIII NIII NaII FeIII SiIV ZrIV W a v e l e n g t h ( ˚ A ) − − Residuals
Fig. A.6 (continued): FEROS spectrum of HD 127493 (gray) and the final model (red).
Article number, page 44 of 48. Dorsch et al.: The chemical composition of HZ 44 and HD 127493 . . . . . . NormalizedFlux
NIII NaII NIII NIII NIII NIII NIII SiIV CaIII NIII CaIII NIII NIII NIII NeII NIII NIII NIII NeII NeII NaII TiIV NeII CaIII TiIV SiIV SiIV NaII CaIII NeII NeII NIII NeII NII NII NeII NeII NeII NeII CaIII NeII NII NII NII ArIV NaII NII NeIII NeIII NeIII NaII NeII NeIII NeIII NeIII − − Residuals . . . . . . . NormalizedFlux
NaII NIII AlIII AlIII MgII MgII MgII NaII SIVNaII CaIII SIVNIII NIII NeII NeII AlIII NIII CaIII NIII NIII NIII NIII AlIII NII NIII NIII NIII NIII PIV PIV PIV PIVNIII NIII NIII NIII PIVNII SiIII SiIII CaIII NIII NIII NII NIII NIV NIV NII NIII NIII NII NIII NIII NIII − − Residuals . . . . . . NormalizedFlux
TiIV TiIV NIII NII NIII NIII NIII NIII NII NIII SiIV SiIV SiIV NIII NIII NIII NIII NII NIII CIII CIII CIII SiIV SiIV SiIV NII TiIV SIV SiIV SiIV SiIV SiIV SiIV TiIV NII NIII SiIV SiIV SiIV SiIV SiIV SiIV SiIV SiIV SiIV SiIV NII NIV NIV NIV NIII SiIII PIVNIII NIII − − Residuals . . . . . . NormalizedFlux
NII NIV NII NII SiIV SiIV NII NIV NII SiIII SiIII SiIII MgII MgII CaIII NIII NIII NIII CaIII NII CIII NIII NIII NIII NIII NIII NIII NIII NIII SIVNIII NIII CaIII ArIII NII NIII NIII NIII NIII SVSVNIII NIII NIII W a v e l e n g t h ( ˚ A ) − − Residuals
Fig. A.6 (continued): FEROS spectrum of HD 127493 (gray) and the final model (red).
Article number, page 45 of 48 & A proofs: manuscript no. HZ44_HD127493 . . . . . . . . . NormalizedFlux
SIVCaIII FeIV CaIII CaIII PVPVSiIV SiIV CaIII NII GeIV NII FeV NII NII ArIII NII NII NII FeIV NII NII NII NII NII CaIII NII NII NII NIII NII PIV PIVNIII NIII NII NII FeIV NII CaIII CaIII NIII NIII NIII CaIII − − Residuals . . . . . . . . . NormalizedFlux
NIII GeIV NII NII NIII PVNIII NIII NIII CaIII NIII NIII NIII AlIII PVSIII PIV AlIII AlIII NII NII NII NII NII NII NII NIII NIII NII NII NII NII NII NII NII NII FeIV NeII NIV CaIII NIII NIII NIV NIV NIII NIII − − Residuals . . . . . . . . . NormalizedFlux
SIII SiIV SiIV NIV CaIII PIV FeIII PIV FeIII NIV CaIII NIII NII NIII NIII MgII MgII NIII NIII CaIII NIII NIII CaIII NIII FeIII FeIII FeIII NIII FeIII NIII FeIII NIII FeIII CaIII FeIII SiIV NII SiIV FeIII NIII NII NIII NII CaIII NIII NIII CaIII NiIII NII NII NIII NII NIII CaIII − − Residuals . . . . . NormalizedFlux
FeIII NiIII NIII TiIV SiIV SiIVMgII MgII NeII NeII NiIII SiIV SiIV SiIV SiIV SiIV SiIV NeII NeII NIII NIII NiIII NiIII NII SiIV SiIV NII ZrIV NII SiIV SiIV SiIV SiIV SiIV SiIV TiIV NiIII SiIII NII NII CaIII NII NiIII TiIV NiIII SIVTiIV NII SIVNiIII W a v e l e n g t h ( ˚ A ) − − Residuals
Fig. A.6 (continued): FEROS spectrum of HD 127493 (gray) and the final model (red).
Article number, page 46 of 48. Dorsch et al.: The chemical composition of HZ 44 and HD 127493 . . . . . . . . . NormalizedFlux
TiIV NiIII NII NiIII NiIII NII NII NII NII SIVNiIII NII NII NII NiIII CaIII NiIII CaIII NiIII OIII NIII FeIII CaIII − − Residuals . . . . . . . . . NormalizedFlux
NII SiIV NII NII NII NIII NIII CIII AlIII NII SIVNIII AlIII NIV SiIII FeIII NII FeIII NII CIII SrIV ZrIV CIV SiIV CIV − − Residuals . . . . . . . NormalizedFlux N a I N a I NIII NIII FeIII NIII CIII FeIII FeIII NIII FeIII FeIII SiIV SiIV FeIII SIV SVSiIV SiIV SiIV SiIV SiIV SiIV FeIII TiIV TiIV TiIV TiIV FeIII NII NII NII FeIII SiIII NII NIII NIII SVFeIII FeIII NII NII FeIII NII FeIII FeIII NII CrIV NIII NII NII NII NIII FeIII NII NIII FeIII − − Residuals . . . . . . . . NormalizedFlux
NII FeIII FeIII FeIII NII FeIII FeIII PIV FeIII FeIII FeIII FeIII FeIII FeIII FeIII NII FeIII FeIII FeIII CaIII NIII NII NIII NIII W a v e l e n g t h ( ˚ A ) − − Residuals
Fig. A.6 (continued): FEROS spectrum of HD 127493 (gray) and the final model (red).
Article number, page 47 of 48 & A proofs: manuscript no. HZ44_HD127493 . . . . . . . . . NormalizedFlux
NeII NeIII NII NeIII NeIII NeIII SIVNeIII NeIII PIV FeIII NII FeIII NeII NII NII FeIII FeIII NII PIV CaIII NII NII FeIII GeIV FeIII FeIII GeIV NeIII CaIII NIV NIV NeII TiIV SIVNII TiIV NeII NaII SIVNeII NII NaII − − Residuals . . . . . . NormalizedFlux
NeII NeII NaII NeIII NeIII NII NeIII TiIV GeIV CaIII SiIV SiIV SiIV SIVNII SiIV NIIMgII NIIMgII NII NII NaII NIII CaIII NII NIV CaIII NIII − − Residuals . . . . . . . . . . NormalizedFlux
NII GeIV CaIII NIII NIII NIII NIII NIII NIII NIII NIII NII CaIII NIII NII NII NIII NIII NeII NeII NIII NeII NeII SIVNeII NIII NIII NaII NaII NII NeII NeII NeII NeII NeII CaIII SiIV SiIV NaII MgII MgII SIVNeII NeII SIV SIV SiIV SiIV SiIV SiIV NeII SiIV SiIV NeII NII − − Residuals . . . . . . . NormalizedFlux
NII NaII NaII NII NeII NII SIVNII CaIII NII NII NII NII SiIV SiIV SiIV TiIV SIV SiIV SiIV W a v e l e n g t h ( ˚ A ) − − Residuals