Discovery of a large population of Nitrogen-Enhanced stars in the Magellanic Clouds
José G. Fernández-Trincado, Timothy C. Beers, Dante Minniti, Leticia Carigi, Beatriz Barbuy, Vinicius M. Placco, Christian Moni Bidin, Sandro Villanova, Alexandre Roman-Lopes, Christian Nitschelm
DDraft version October 2, 2020
Typeset using L A TEX twocolumn style in AASTeX62
Discovery of a large population of Nitrogen-Enhanced stars in the Magellanic Clouds
Jos´e G. Fern´andez-Trincado, Timothy C. Beers, Dante Minniti,
3, 4
Leticia Carigi, Beatriz Barbuy, Vinicius M. Placco,
2, 7
Christian Moni Bidin, Sandro Villanova, Alexandre Roman-Lopes, andChristian Nitschelm Instituto de Astronom´ıa y Ciencias Planetarias, Universidad de Atacama, Copayapu 485, Copiap´o, Chile Department of Physics and JINA Center for the Evolution of the Elements, University of Notre Dame, Notre Dame, IN 46556, USA Depto. de Cs. F´ısicas, Facultad de Ciencias Exactas, Universidad Andr´es Bello, Av. Fern´andez Concha 700, Las Condes, Santiago,Chile Vatican Observatory, V00120 Vatican City State, Italy Instituto de Astronom´ıa, Universidad Nacional Aut´onoma de M´exico, A.P. 70-264, 04510, Ciudad de M´exico, Mexico Universidade de S˜ao Paulo, IAG, Rua do Mat˜ao 1226, Cidade Universit´aria, S˜ao Paulo 05508-900, Brazil NSF’s Optical-Infrared Astronomy Research Laboratory, Tucson, AZ 85719, USA Instituto de Astronom´ıa, Universidad Cat´olica del Norte, Av. Angamos 0610, Antofagasta, Chile Departamento de Astronom´ıa, Casilla 160-C, Universidad de Concepci´on, Concepci´on, Chile Departamento de Astronom´ıa, Universidad de La Serena - Av. Juan Cisternas, 1200 North, La Serena, Chile Centro de Astronom´ıa (CITEVA), Universidad de Antofagasta, Avenida Angamos 601, Antofagasta 1270300, Chile
ABSTRACTWe report the APOGEE-2S+ discovery of a unique collection of nitrogen-enhanced mildly metal-poor giant stars, peaking at [Fe/H] ∼ − .
89 with no carbon enrichment, toward the Small and LargeMagellanic Clouds (MCs), with abundances of light- (C, N), odd-Z (Al, K) and α − elements (O, Mg, Si)that are typically found in Galactic globular clusters (GCs). Here we present 44 stars in the MCs thatexhibit significantly enhanced [N/Fe] abundance ratios, well above ([N/Fe] > ∼ + 0 .
6) typical Galacticlevels at similar metallicity, and a star that is very nitrogen-enhanced ([N/Fe] > +2 . Keywords:
Chemically peculiar stars (226) - Large Magellanic Cloud (903) - Small Magellanic Cloud(1468) - Globular star clusters (656) - Asymptotic giant brach stars (2100) - Red giantbranch (1368) - Semi-regular variable stars (1444) - Stellar abundances (1577) INTRODUCTIONIt has been well-established that some metal-poor( − . < [Fe/H] < − .
7) stars within the Milky Waymay produce a [N/Fe] over-abundance (i.e., N-rich stars;Bessell & Norris 1982; Beveridge & Sneden 1994; John-
Corresponding author: Jos´e G. Fern´[email protected] son et al. 2007; Fern´andez-Trincado et al. 2016; Martellet al. 2016; Fern´andez-Trincado et al. 2017; Schiavonet al. 2017; Fern´andez-Trincado et al. 2019a,b,c, 2020)that replicates or exceeds the chemical patterns seenin the so-called second-generation stars in GCs in thebulge and halo of the Milky Way (MW) (Fern´andez- Second-generation is used here to refer to groups of stars inthe halo and star clusters that display altered (i.e., different to a r X i v : . [ a s t r o - ph . GA ] S e p Trincado et al. 2019d; M´esz´aros et al. 2020), and as suchwe would expect to find similar chemical signatures inthe Large Magellanic Cloud (LMC), that also has a halo(Minniti et al. 2003; Borissova et al. 2006). On the con-trary, for metal-poor field stars with metallicities downto [Fe/H]= − .
7, the [N/Fe] ratio is not higher than+0.5.Galactic GCs are expected to lose mass through pro-cesses like evaporation and tidal stripping (e.g., Baum-gardt & Makino 2003), and the favored hypothesis forthe origin of the N-rich stars is that they were once partof a GC. This conjecture appears to be well-supportedby the chemo-kinematics similarity between a numberof nitrogen-enriched MW field stars and its possible GCprogenitors (see, e.g., Martell et al. 2016; Tang et al.2020; Fern´andez-Trincado et al. 2019a,a, 2020). Alter-natively, it has been suggested that such a N-rich popu-lation could include the oldest stars in the MW, whichcould have been born in high-density environments (Chi-appini et al. 2011; Bekki 2019).The N-rich population is often typified by largerN over-abundances, accompanied by decreased abun-dances of carbon ([C/Fe] (cid:46) +0 .
15) and α − elements(O, and Mg). Sometimes they exhibit atmospheresextremely enriched in aluminum ([Al/Fe] > +0 .
5) and s -process elements, suggesting that some of them couldbe objects in the AGB evolutionary stages that haveundergone the hot bottom burning (see e.g., Fern´andez-Trincado et al. 2016; Pereira et al. 2017; Fern´andez-Trincado et al. 2017, 2019a), including a few caseswhich became strongly enriched in phosphorus (see,e.g., Masseron et al. 2020), which could be biased to-wards red giant branch (RGB) stars in previous studies(Schiavon et al. 2017), or could be objects chemicallyenriched by an AGB companion (e.g., Cordero et al.2015; Fern´andez-Trincado et al. 2019c).The existence of N-rich stars in specific environmentshas proven to have important implications in the chem-ical makeup of multiple populations (MPs) in the con-text of GC evolution across a wide range of metallicity(see, e.g., Renzini et al. 2015; Fern´andez-Trincado et al.2019d; M´esz´aros et al. 2020). Establishing whether N-rich stars in the MW and/or nearby Local Group sys-tems formed in a GC could either reveal that MP pop-ulations can also form, to some extent, in lower-densityenvironments (e.g., Savino & Posti 2019), as well as pro-vide important insights on the assembly history of theirhost systems, in particular on the role of GC disruption. those of MW field stars) light- element abundances (He, C, N, O,Na, Al, and Mg). While the abundance properties of N-rich stars havebeen limited to GC stars and the inner/outer (up to (cid:46)
100 kpc) stellar halo (Martell et al. 2016; Fern´andez-Trincado et al. 2017, 2019a,b) and widely explored, littleis known of these stars in nearby dwarf galaxies thatsurround the MW, even though some attempts to searchfor dissolved GCs in these systems via the investigationof chemical anomalies have been tried (e.g., Lardo et al.2016).The Apache Point Observatory Galactic EvolutionEnvironment (APOGEE: Majewski et al. 2017), is cur-rently obtaining near-IR spectra for stars in the Smalland Large Magellanic (SMC/LMC) Clouds (Nideveret al. 2020), providing us with an excellent window toexamine the presence of disrupted GCs in nearby Lo-cal Group galaxies. In this Letter, we report the dis-covery of a large population of N-rich stars likely asso-ciated with GC dissolution and/or evaporation in theSMC/LMC. To our knowledge, none of the large spec-troscopic surveys of the SMC/LMC system have so farincluded measurements of nitrogen abundances.This work is organized as follows. In Section 2, wediscuss the data and selection criteria employed to createthe parent stellar sample used throughout the paper. Wepresent our analysis and conclusions in Section 3. DATAIn this work, we manually re-examined the high-resolution ( R ∼ H -band ( λ ∼ µ m) from the APOGEE instrument (Gunn et al.2006; Wilson et al. 2019) that operates on the Ir´en´eeDu Pont 2.5m telescope (Bowen & Vaughan 1973) at LasCampanas Observatory (LCO, APOGEE-2S) as part ofthe incremental 16th data release of SDSS-IV (Blantonet al. 2017; Ahumada et al. 2020). These spectra includeinternal data through March 2020 from the APOGEE-2survey (Majewski et al. 2017, hereafter APOGEE-2S+)toward the Southern Hemisphere. Targeting strategiesfor APOGEE-2+, data reduction of the spectra, deter-mination of radial velocities, and atmospheric parame-ters are fully described in Holtzman et al. (2015), Nide-ver et al. (2015), Garc´ıa P´erez et al. (2016), and Za-sowski et al. (2017). All the spectra analyzed in thiswork are in the following ranges: (i) S/N >
60 pixel − ; (ii) < T eff < − . < log g < . g ; ( iii ) ASPCAPFLAG == 0.We identified potential GC debris over ∼ − . < ∼ [Fe/H] < ∼ − .
7) stars toward theMCs in the [N/Fe]–[Fe/H], plane following the samemethodology as described in Fern´andez-Trincado et al.(2019a). This yielded the serendipitous discovery of 44stars toward the MCs with stellar atmosphere strongly
Figure 1.
Density distribution on the sky of the stars selected as members of the SMC (panel a) and LMC (panel b) fromthe Gaia Collaboration et al. (2018), and the stars in the APOGEE 2S+ footprint are shown in panels (c) and (d). The N-richstars are marked as lime dot symbols. MC clusters from Bica & Schmitt (1995), Palma et al. (2016), and Milone et al. (2020)are marked as gray squares, gray triangles, and orange diamond symbols, respectively. The large blue and green circles markthe tidal radius of NGC 362 and NGC 104, respectively.
Figure 2.
Panels (a) and (d): The proper motion plane (mas/yr) for the selected SMC, NGC 104, and NGC 362 ( top ), andLMC ( bottom ) candidates from Gaia Collaboration et al. (2018). The blue and green concentric ellipses show the 1 σ , 2 σ , 3 σ and 4 σ levels, while the while ellipses are the same defined in Nidever et al. (2020). The lime dots in all the panels refer to theN-rich stars, with black open circles indicating the confirmed semi-regular (SR) variables (Jayasinghe et al. 2020). Panels (b)and (e): Radial velocity-metallicity plot for SMC/LMC candidate stars cross-identified in APOGEE-2S+ (gray dots). The redlines are the same as defined in Nidever et al. (2020). Panels (c) and (f): The density distribution of stars in the Gaia
DR2Color-Magnitude Diagram (CMD). The pink open circles indicate the location of the SR variables, while the pink dashed lineroughly separates the region dominated by Magellanic star clusters and the possible location of evolved AGB stars. enriched in nitrogen, which are typically found amongthe so–called second-generation of stars in Galactic GCs.The newly identified N-rich stars are shown as lime opensymbols in Figure 1.Although a handful of N-rich star candidates havebeen identified in the APOGEE survey toward the in-ner halo (Martell et al. 2016) and Galactic Bulge (Schi-avon et al. 2017), based on the
ASPCAP /APOGEE DR12catalog, the
ASPCAP pipeline (Garc´ıa P´erez et al. 2016)contains some caveats that hamper a profound explo-ration and characterization of the mildly metal-poor N-rich population (for a review, see Fern´andez-Trincadoet al. 2019a). Here, we perform a spectral synthesis analysis, in-dependently of the
ASPCAP pipeline, to disentangle theunderlying C, N, and O abundances from the C O, C N, and OH band strengths. To this purpose,we performed an LTE analysis with a MARCS grid ofspherical models with the
BACCHUS code (Masseron et al.2016), adopting the same methodology as described inFern´andez-Trincado et al. (2016, 2017, 2019a,b,c,d). Itis important to keep in mind that
ASPCAP uses a globalfit to the continuum in three detector chips indepen-dently, while we place the pseudo-continuum in a regionaround the lines of interest. We believe that our manualmethod is more reliable, since it avoids possible shifts
Figure 3.
Distributions of various elemental-abundance ratios from the APOGEE-2S+ survey, represented by iso-abundancecontours for the MW stars (orange), SMC (black), and LMC (red) stars, and Galactic GCs (blue crosses) from M´esz´aros et al.(2020). Bright N-rich RGB stars in the SMC and LMC are marked as lime circles and squares, respectively, while the greenunfilled circles indicate N-rich AGB stars in the SMC. The SR variables in the SMC and LMC are highlighted with black circlesand squares, respectively. in the continuum location due to imperfections in thespectral subtraction along the full spectral range.In order to provide a consistent chemical analysis, were-determine the chemical abundances by means of acareful line selection, and measure abundances basedon a line-by-line basis with the
BACCHUS code, and byadopting the line selection for the various elements asin Fern´andez-Trincado et al. (2019a). Finally, we re-derived chemical abundances adopting as input the un-calibrated effective temperatures (T unceff ), surface gravi-ties log g unc and the overall metallicity ([M/Fe]) fromthe ASPCAP pipeline. We do not calculate chemical abun-dances based on the photometric atmospheric parame-ters, as they become error dominated for stars towardthe MCs, due the difficulty of calculating accurate red-denings in these regions (see, e.g., Nidever et al. 2020), making them unsuitable to estimate precise chemicalabundances for stars in the inner MCs. RESULTS AND ANALYSISWe find that the newly identified N-rich stars spana wide range of metallicities ( − . < [Fe/H] < − . ∼ − .
89, and that they exhibit nitro-gen abundances well above typical Galactic levels overa range of metallicities, which is (cid:38) σ above the typ-ical MW [N/Fe]. It seems likely that whatever nucle-osynthesis process is responsible for these nitrogen over-abundances in the field of the MCs is similar to thatwhich caused the unusual stellar populations in Galac-tic GCs at similar metallicity.Figures 1a–d reveal the existence of a large number ofN-rich stars toward the MCs. There are 34 out of 44N-rich stars located at the center of the SMC, whereas m )0.40.60.81.01.2 N o r m a li z e d F l u x C NS/N = 156
Semi-regularvariableSMC: 2M01172841 7554103 ("AGB-O")
A(N) = 7.251.5355 1.5360 1.5365 1.5370Wavelength ( m )0.40.60.81.01.2 N o r m a li z e d F l u x C NS/N = 57
SMC: 2M01160427 7304175 (BrtRGB)
A(N) = 9.111.5505 1.5510 1.5515 1.5520Wavelength ( m )0.40.60.81.01.2 N o r m a li z e d F l u x C NS/N = 354
SMC: 2M01122821 7302283
A(N) = 7.491.5280 1.5285 1.5290Wavelength ( m )0.40.60.81.01.2 N o r m a li z e d F l u x C NS/N = 125
SMC: 2M01103557 7326490
A(N) = 7.95 1.5505 1.5510 1.5515 1.5520Wavelength ( m )0.40.60.81.01.2 N o r m a li z e d F l u x C NS/N = 89
Semi-regularvariableLMC: 2M06413441 7003239 (BrtRGB)
A(N) = 7.611.5320 1.5325 1.5330 1.5335Wavelength ( m )0.40.60.81.01.2 N o r m a li z e d F l u x C NS/N = 119
LMC: 2M05445497-7100192 (BrtRGB)
A(N) = 7.841.5505 1.5510 1.5515 1.5520Wavelength ( m )0.40.60.81.01.2 N o r m a li z e d F l u x C NS/N = 94
LMC: 2M04134909 7222201 (FntRGB)
A(N) = 7.611.5455 1.5460 1.5465 1.5470Wavelength ( m )0.40.60.81.01.2 N o r m a li z e d F l u x C NS/N = 93
LMC: 2M06373127 7036477 (FntRGB)
A(N) = 7.55
Figure 4.
High-resolution near-IR H -band spectrum of the newly identified N-rich stars in the Small ( left ) and Large ( right )Magellanic Clouds, covering spectral regions around the C N band (orange squares). Superimposed is the best-fit of aMARCS/
BACCHUS spectral synthesis (black line). The legends in each panel show the absolute abundance, A (N), and thesignal-to-noise (S/N) in the region of the feature, respectively. ten stars in our sample reside on the periphery of theLMC.Figures 2a;d show the proper motions of Gaia
DR2,confirming that the N-rich stars are permanent residentsof the MCs. In the case of N-rich stars in the SMC, it isclearly visible that its proper motion distribution devi-ates by more than 4 σ from the nominal proper motionsof the NGC 104 and NGC 362 GCs. Figures 2b;e also reveal that the radial-velocity distributions differ fromthose of the field GCs, while the Color-Magnitude Dia-gram (CMD) using Gaia bands (see Figures 2c;f) alsorules out the possibility these N-rich stars are stellar de-bris of these two Galactic GCs. This is also supportedby inspection of [Fe/H]; the N-rich stars exhibit a largermetallicity scatter, on average being more metal richthan NGC 362 and more metal poor than NGC 104.Based on these properties, we conclude that these are bona fide
N-rich stars in the MCs, which are chemicallyidentical to those identified toward the bulge and haloof the MW (see, e.g., Fern´andez-Trincado et al. 2017,2019a,c,d).Figure 3 presents some of the light-, odd-Z, and α -element patterns, and demonstrates a very distinct sep-aration in nitrogen, with a star-to-star scatter ∆ [N / Fe] (cid:38) +0 .
28 dex and ∆ [C / Fe] (cid:38) +0 .
25 dex, which is mod-erately anti-correlated with [C/Fe], and runs roughlybetween { [C/Fe], [N/Fe] } = {− .
6, +0 . } and { +0 . . } . We have found mean values for [C/Fe], [N/Fe],[O/Fe], [Mg/Fe], [Al/Fe], [Si/Fe], [K/Fe], [Ce/Fe], and[Nd/Fe] that are compatible with Galactic GC stars(M´esz´aros et al. 2020) at similar metallicity. There isalso a star with [N/Fe] (cid:38) +2 .
42 that exceeds the extremeabundance patterns seen in Galactic GCs, highlightingthe uniqueness of these stars. Overall, we can see clearlyfrom Figure 3 that our sample of stars in the MCs be-have in a similar way as MW GC stars, supporting theidea that most of the newly identified stars could berelated to MC GCs.The newly identified N-rich population is separatedrelatively cleanly from MW stars and MC stars in the[C/Fe] vs. [N/Fe] and [N/Fe] vs. [Al/Fe] planes. In gen-eral, these N-rich stars exhibit slightly higher abundanceratios in Al, Si, Ti, and Ni compared to the SMC andLMC populations, but they exhibit lower abundance ra-tios in O, Mg, Al, Si, K, and C compared to MW fieldstars, with the α − elements (O, Mg, Si, and Ca) at com-parable levels ( ∼ +0 .
1) to low- α halo MW field stars(e.g., Hayes et al. 2018).The star-to-star scatter is between 0.1 – 0.3 dex forthe different chemical species, being slightly lower forthe α − elements. Therefore, the star-to-star scatter iniron and other chemical species could be attributed todifferent progenitors, which could explain the observedchemical anomalies toward the MCs, in a similar manneras observed in and around the MW halo metal-poor starstoday. The mildly metal-poor N-rich stars toward theMCs may have formed following minor merger events inthe early history of the MCs. However, there are otherobservational features in our sample that allow us toinvoke other possible scenarios to explain the observedabundance patterns toward the MCs.Our sample includes five SR variable stars reportedin the ASAS-SN Catalog of Variable Stars (Jayasingheet al. 2020). Four of them are located toward the SMC,with one been selected as a possible O-rich AGB starbased on its position in the (J-Ks, H) diagram (see Nide-ver et al. 2020). We also identified a SR variable inour sample toward the LMC, selected as a bright RGB in Nidever et al. (2020). These SR stars have peri-ods between ∼
85 and 757 days and variability ampli-tudes between 0.17 and 0.51 mag in the V-band. Inconclusion, we find evidence that the SR stars are nei-ther carbon rich nor oxygen rich, but exhibit lower car-bon and oxygen abundance ratios, [C/Fe] < +0 .
15 and[O/Fe] (cid:46) +0 .
23. It is worthing to mention that no bias oruncertainties are introduced in our spectroscopic anal-ysis, as is the case for, e.g., shorter-period Cepheids orRR Lyrae stars (Pancino et al. 2015).Thus, the observed nitrogen over-abundances and themodest enhancements of the s -process elements, coupledwith the apparent variability of these SR stars, sug-gest that some of the evolved objects could be likelyintermediate-mass ( ∼ (cid:12) ) AGB stars (one of thelikely agent that self-enriches the GCs) that have un-dergone hot bottom burning and are becoming N-rich,according to chemical evolution models (Karakas et al.2018), but without production of significant amountsof aluminum, as envisioned by Ventura et al. (2016).These SR N-rich stars have remarkably stronger C Nlines (see Figure 4) compared to other stars with sim-ilar relevant parameters; it can be asserted that thesehave much higher nitrogen abundance. The presence ofsuch young, mildly metal-poor stellar populations in theMCs has important implications. Thus, the interpreta-tion of our results depends crucially on establishing theevolutionary stage of the stars under analysis. It is alsoimportant to note that there are no known MC GCswithin an angular separation of approximately one ar-cmin of these stars.In this context, one can immediately notice that twosub-samples occupy different loci in the CMD displayedin Figure 2c;f. N-rich stars with G (cid:46) . G (cid:46) . G magnitudes roughly oc-cupy the same locus as the bright RGB stars in the MCstellar clusters. These stars are tagged as genuine mi-grants from MC GCs (hereafter N-rich BrRGB stars),and are among the oldest objects in the MCs. The ex-istence of N-rich AGB stars in our sample can be alsofurther assessed by the possible presence of circumstel-lar dust (Habing 1996), as the N-rich AGB stars occupya locus towards colors that are redder than those N-richBrRGB stars in the CMD diagram. In particular, 55%of the N-rich stars in our sample inhabit the AGB partof the diagram, which provides further evidence for animportant contribution of AGB stars to our N-rich sam-ple.Although these stars have elemental abundances con-sistent with each other, we find that in the N-rich AGBstars the oxygen abundance ratios – generally lower thanthe [O/Fe] of N-rich BrRGB stars–this lends further sup-port to the notion that the two populations do not sharethe same origin.It is also interesting to note that all the N-rich AGBstars in our sample were identified toward the SMC sys-tem, while the N-rich BrRGB stars are present in both,and likely could be part of the oldest stars in the MCs.We also conclude that there is significant evidence fora large contribution of possible AGB stars to our sam-ple toward the MCs, suggesting that the detection ofN-rich stars toward the MW has been biased towardsRGB stars (e.g., Schiavon et al. 2017), which should re-sult in a substantial difference in AGB contribution tothe N-rich sample and the rest of the field, as alreadynoted in Fern´andez-Trincado et al. (2019a).Our finding can be understood in terms of differentscenarios. Here, we conjecture that there may be atleast two possible channels for the production of N-richstars in the MCs: ( i ) the N-rich BrRGB stars could beformer members of a population of GCs that was pre-viously dissolved and/or evaporated in the LMC/SMC,and were later incorporated into the field of the MCsthemselves–’smoking gun’ evidence that they have beenaccreted along with their now-disrupted host GCs. Sucha scenario could potentially explain the predominance ofN-rich BrRGB stars that are currently not gravitation-aly bound to any MC clusters. The chemical patternsof these stars are identical or comparable to those seenin old MW GC stars (e.g., M´esz´aros et al. 2020), andpossibly associated with MC GCs, with ages between ∼ (cid:38) ii ) On theother hand, the discovery of a significant population ofN-rich stars in the AGB evolutionary stage (and pos-sibly of intermediate-mass), further supports the ideathat AGB stars are possibly one of the key players inthe pollution of the intracluster medium (e.g., Venturaet al. 2016) proposed to explain the formation of MPsin GCs.The presence of such a significant young and moder-ately metal-poor stellar populations in the MCs would have interesting consequences for the understanding ofthe formation and evolution of GC systems in the Lo-cal Universe, i.e., the presence of star-to-star abundancespreads in this possible ”young” N-rich AGB populationappears to be at odds with the apparent near-exclusivityof this population within old GCs. 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P., Milone, A. P., Marino, A. F., & Dotter, A.2019, ApJ, 871, 140Lardo, C., Battaglia, G., Pancino, E., et al. 2016, A&A,585, A70 T a b l e . B a s i c p a r a m e t e r s a nd A bund a n c e s o f t h e M C N - r i c h s t a r s . A P O G EE − I d T a r g e t C l a ss G - b a nd V i s i t s S / N R V σ R V T e ff l og g ξ t [ M / H ][ C / F e ][ N / F e ][ O / F e ][ M g/ F e ][ A l / F e ][ S i / F e ][ K / F e ][ C a/ F e ][ T i / F e ][ F e / H ][ N i / F e ][ C e / F e ][ N d / F e ][ Y b / F e ] m ag p i x e l − k m s − k m s − K d e xk m s − M − L M C / B rt R G B . . . . . − . − . + . + . + . − . + . + . + . + . − . + . + . + . + .
72 2 M − L M C / B rt R G B . . . . . − . − . + . + . + . − . + . + . + . + . − . + . + . + . + .
69 2 M − L M C / B rt R G B . . . . . − . + . + . + . + . − . + . + . + . + . − . − . + . + . ... M − L M C / F n t R G B . . . . . − . + . + . + . + . − . + . + . + . − . − . + . + . + . + .
57 2 M − L M C / B rt R G B . . . . . − . − . + . + . + . + . + . − . + . + . − . + . + . + . + .
64 2 M − L M C / F n t R G B . . . . . − . + . + . + . + . − . + . − . + . − . − . + . + . + . + .
58 2 M − L M C / B rt R G B . . . . . − . − . + . + . + . − . + . − . + . + . − . − . + . ...... M − L M C / B rt R G B . . . . . − . − . + . + . + . − . + . − . + . + . − . − . + . + . + .
98 2 M − L M C / F n t R G B . . . . . − . − . + . + . + . − . + . + . + . + . − . + . + . + . ... M − L M C / ... . . . . . − . − . + . + . + . − . + . − . + . + . − . − . + . + . + .
05 2 M − S M C / A G B - O . . . . . − . − . + . + . − . − . + . − . + . − . − . − . + . ...... M − S M C / A G B - O . . . − . . − . − . + . + . + . − . + . − . + . + . − . − . + . + . + .
65 2 M − S M C / B rt R G B . . . . . − . − . + . + . + . − . + . + . + . + . − . + . + . + . + .
65 2 M − S M C / F n t R G B . . . . . − . − . + . + . + . − . + . − . + . + . − . + . + . + . + .
97 2 M − S M C / F n t R G B . . . . . − . − . + . + . − . − . + . − . − . + . − . − . + . + . ... M − S M C / B rt R G B . . . . . − . + . + . − . ...... − . ...... − . − . ... + . + . ... M − S M C / F n t R G B . . . . . − . − . + . + . + . − . + . − . + . ... − . + . ......... M − S M C / F n t R G B . . . . . − . − . + . + . + . − . + . − . + . + . − . + . + . + . + .
04 2 M − S M C / F n t R G B . . . . . − . − . + . + . + . − . + . − . + . + . − . − . ...... + .
88 2 M − S M C / A G B - O . . . − . . − . − . + . + . + . − . + . − . + . − . − . − . + . + . ... M − S M C / A G B - O . . . . . − . − . + . + . + . − . + . − . + . − . − . − . + . + . ... M − S M C / F n t R G B . . . . . − . − . + . + . − . − . + . − . − . − . − . − . + . ... + .
91 2 M − S M C / B rt R G B . . . − . . − . + . + . + . − . − . + . + . + . ... − . − . + . ...... M − S M C / F n t R G B . . . . . − . − . + . + . − . − . + . − . + . + . − . + . ... + . ... M − S M C / ... . . ... − . . − . − . + . + . + . ... + . − . + . + . − . + . + . + . ... M − S M C / ... . . ... − . . − . − . + . + . + . ... + . − . + . − . − . − . + . + . ... M − S M C / ... . . ... − . . − . − . + . + . + . − . + . − . + . + . − . − . + . + . ... M − S M C / ... . . ... − . . − . − . + . + . + . − . + . − . + . + . − . − . + . + . + .
58 2 M − S M C / ... . . ... . . − . − . + . + . + . − . + . − . + . + . − . − . + . + . ... M − S M C / ... . . ... . . − . − . + . + . + . − . + . − . + . + . − . − . + . ... + .
72 2 M − S M C / ... . . ... . . − . − . + . + . + . − . + . − . + . + . − . − . + . + . + .
61 2 M − S M C / ... . . . . . − . − . + . + . + . − . − . − . + . + . − . − . + . + . ... M − S M C / ... . . ... . . − . − . + . + . + . − . + . − . + . + . − . − . + . + . ... M − S M C / ... . . ... . . − . − . + . + . + . − . + . − . + . + . − . − . + . ... + .
65 2 M − S M C / ... . . ... . . − . − . + . − . + . − . + . − . + . − . − . − . + . + . ... M − S M C / ... . . ... . . − . − . + . + . + . − . + . − . + . − . − . − . + . + . + .
88 2 M − S M C / ... . . . . . − . − . + . + . + . − . + . − . + . + . − . − . + . + . + .
75 2 M − S M C / ... . . . . . − . − . + . + . + . − . + . − . + . + . − . − . ... + . + .
53 2 M − S M C / ... . . ... . . − . − . + . + . − . − . + . − . + . + . − . − . + . + . + .
76 2 M − S M C / ... . . ... . . − . − . + . + . + . − . + . − . + . + . − . − . + . + . + .
38 2 M − S M C / ... . . ... . . − . − . + . − . − . − . + . − . + . + . − . − . + . ...... M − S M C / ... . . . . . − . − . + . + . + . − . + . − . + . + . − . − . ... + . + .
84 2 M − S M C / ... . . ... . . − . − . + . + . + . − . + . − . + . − . − . − . ... + . + .
96 2 M − S M C / ... . . ... . . − . − . + . + . − . − . + . − . − . + . − . − . + . + . + .1