Spitzer Photometry of ~1 Million Stars in M31 and 15 Other Galaxies
aa r X i v : . [ a s t r o - ph . GA ] D ec Spitzer
Photometry of ∼ Million Stars in M 31 and 15 Other Galaxies Rubab Khan , ABSTRACT
We present
Spitzer
IRAC 3 . − µ m and MIPS 24 µ m point-source catalogs forM 31 and 15 other mostly large, star forming galaxies at distances ∼ . −
14 Mpcincluding M 51, M 83, M 101 and NGC 6946. These catalogs contain ∼ ∼ ,
000 in M 31 and ∼ ,
000 in the other galaxies. They were createdfollowing the procedures described in Khan et al. (2015b) through a combination ofpoint spread function (PSF) fitting and aperture photometry. These data productsconstitute a resource to improve our understanding of the IR-bright (3 . − µ m) point-source populations in crowded extragalactic stellar fields and to plan observations withthe James Webb Space Telescope. Subject headings: catalogs — surveys — techniques: photometric — infrared: stars —galaxies: individual (M 31, M 51, M 83, M 101, NGC 6946)
1. Introduction
The Infrared Array Camera (IRAC, Fazio et al. 2004) and the Multiband Imaging Photome-ter (MIPS, Rieke et al. 2004) instruments aboard the
Spitzer
Space Telescope (
Spitzer , Werner et al.2004) have collected a vast archive of mid-infrared (mid-IR) imaging data. This resource makes itfeasible to identify and characterize mid-IR luminous stars in the crowded and dusty disks of largestar forming galaxies despite difficulties due to IR emission from interstellar dust, blending andbackground contamination. In Khan et al. (2010) we published the first ever mid-IR point-sourcecatalogs for galaxies significantly beyond the Local Group ( & . ∼ − ∼ , > M ⊙ ) post-main-sequencestars (Khan et al. 2015a). Here we present photometric inventories of the mid-IR point sourcesin the IRAC 3 . µ m, 4 . µ m, 5 . µ m and 8 µ m as well as MIPS 24 µ m images of the Andromeda Based on observations made with the
Spitzer
Space Telescope, which is operated by the Jet Propulsion Laboratory,California Institute of Technology under a contract with NASA. JWST Fellow, NASA Postdoctoral Program, NASA Goddard Space Flight Center, MC 665, 8800 GreenbeltRoad, Greenbelt, MD 20771 Department of Astronomy, Box 351580, University of Washington, Seattle, WA 98195; [email protected] .
14 Mpc) galaxies beyond the Local Group. Our key mo-tivation here is to facilitate targeted follow-up of individual objects and observation planning ofIR-bright extragalactic stellar populations in the upcoming era of the James Webb Space Tele-scope (JWST, Gardner et al. 2006) and the Wide-Field InfrarRed Survey Telescope (WFIRST,Spergel et al. 2015).As the nearest major spiral galaxy to the Milky Way, the Andromeda galaxy (M 31) have beenextensively observed over the years from both ground and space based observatories (e.g., Baade1944; de Vaucouleurs 1958; Massey et al. 2006; Johnson et al. 2012). The Panchromatic HubbleAndromeda Treasury (Dalcanton et al. 2012) mapped roughly a third of M 31’s star forming disk,using 6 filters covering from the ultraviolet through the near-infrared (near-IR) to produce themost detailed picture of resolved extragalactic stellar populations in a galaxy. However, publicavailability of mid-IR stellar catalogs of this galaxy is very limited. Mould et al. (2008) performedmid-IR photometry of point sources on
Spitzer
IRAC and MIPS images of M 31. However, whiletheir paper shows mid-IR color magnitude diagrams containing seemingly many hundred thousandsources, they published only a small fraction ( ∼ −
900 sources at various bands) of the catalog,consisting of the brightest sources in the field. In this paper, we present an extensive mid-IRpoint-source catalog of M 31 consisting of ∼ ,
000 sources, covering the entirety of M 31’s diskincluding the accompanying M 32 and M 110 galaxies.When selecting the other 15 galaxies, we concentrated on those with higher recent star for-mation rate (SFR), as these would have large numbers of short lived, massive, evolved mid-IRbright stars, and we cataloged ∼ ,
000 stars in these galaxies. These catalogs include thehighly star-forming galaxies M 83, NGC 6946, M 101 and M 51 (M 51a and M 51b) which enabledthe first-ever identification of extragalactic candidate analogs of the Galactic stellar behemoth η Carinae (Khan et al. 2015c). We selected these 15 galaxies to span a range of distances and SFRs( ∼ . −
14 Mpc and . . − ∼ M ⊙ / year, see Table 1), and currently there are no public mid-IRstellar catalogs for 13 of these galaxies. Williams et al. (2015) published a mid-IR bright sourcecatalog of M 83 including Spitzer 3 . . µ m band measurements for < ,
000 objects, whilethe M 83 catalog presented here contains Spitzer 3 .
6, 4 .
5, 5 .
8, 8 and 24 µ m band measurements for ∼ ,
000 sources. Likewise, Khan et al. (2010) reported two Spitzer band measurements of < , Spitzer bandmeasurements for ∼ ,
000 sources.For M 31, we used the IRAC 3 . µ m, 4 . µ m, 5 . µ m and 8 µ m mosaics produced by Mould et al.(2008) and the MIPS 24 µ m mosaic produced by Gordon et al. (2006). For the other galaxies,we used the IRAC and MIPS mosaics produced by the Spitzer
Infrared Nearby Galaxies Sur-vey (SINGS, Kennicutt et al. 2003) and the Local Volume Legacy Survey (LVL, Dale et al. 2009).We utilize the full mosaics available for each galaxy. The M 31 mosaics (covering ∼ .
2. Photometry
We obtained the photometric measurements at various wavelengths and combined them toconstruct the point-source catalogs following the procedures established in Khan et al. (2015b).We implement a strict detection criteria by requiring > σ detection of all cataloged sources at3 . µ m and 4 . µ m. We then complement those measurements at the 5 . µ m, 8 . µ m and 24 µ mbands through a combination of point spread function (PSF) fitting photometry and aperturephotometry. For all objects that do not have a > σ detection at these three longer wavelengths,we estimate their 3 σ flux upper limits in those bands.First we select all sources detected through PSF fitting photometry at > σ in both the 3 . µ mand 4 . µ m images within a 1 pixel matching radius as point sources. Next, we search for > σ detections of these point sources in the 5 . µ m and 8 . µ m images within the same matching radius.If no counterpart is found, we attempt to measure the flux at the location of the 3 . / . µ m pointsource through PSF fitting, and failing that, through aperture photometry. For the MIPS 24 µ mimages, we only use aperture photometry due to the much lower resolution and larger PSF sizecompared to the IRAC images , , . Finally, for all objects that do not have a > σ detectionat 5 . µ m, 8 . µ m and 24 µ m, we estimate the 3 σ flux upper limits. The fluxes and upper limitsare transformed to Vega-calibrated magnitudes using the flux zero-points and aperture correctionsprovided in the Spitzer
Data Analysis Cookbook .We used the DAOPHOT/ALLSTAR PSF-fitting and photometry package (Stetson 1992) toconstruct the PSFs, to identify the > σ sources and to measure their flux at all 4 IRAC bands.We used the IRAF ApPhot/Phot tool for performing aperture photometry for all IRAC bandsand the MIPS 24 µ m band. For the four IRAC bands, we use an extraction aperture of 2 . ′′
4, alocal background annulus of 2 . ′′ − . ′′ . . . . µ m band, we use an extraction aperture of 3 . ′′
5, a local background Mean full width half-max (FWHM) of the cryogenic IRAC PSFs are 1 . ′′
66, 1 . ′′
72, 1 . ′′
88 and 1 . ′′
98, and the MIPS24 µ m PSF FWHM is 5 . ′′ http://irsa.ipac.caltech.edu/data/SPITZER/docs/irac/iracinstrumenthandbook/5/ http://irsa.ipac.caltech.edu/data/SPITZER/docs/mips/mipsinstrumenthandbook/50/ http://irsa.ipac.caltech.edu/data/SPITZER/docs/dataanalysistools/ IRAF is distributed by the National Optical Astronomy Observatory, which is operated by the Association ofUniversities for Research in Astronomy (AURA) under cooperative agreement with the National Science Foundation. . ′′ − . ′′ and an aperture correction of 2 .
78. We estimate the local background using a 2 σ outlier rejection procedure in order to exclude sources located in the local sky annulus and correctfor the excluded pixels assuming a Gaussian background distribution. We determine the 3 σ fluxupper limit for each aperture location using the local background estimate.We present the results of our mid-IR photometric survey following the same format as thecatalogs published in Khan et al. (2015b). Tables 2 −
17 list the coordinates (J2000 .
0; RA and Dec)of the point sources followed by their Vega calibrated apparent magnitudes ( m λ ), the associated 1 σ uncertainties ( σ λ ) and (for the 3 . − . µ m bands) the differences between the PSF and aperturephotometry magnitudes ( δ λ ). For the 5 . µ m, 8 . µ m and 24 µ m bands, σ λ = 99 .
99 implies thatthe associated photometric measurement is a 3 σ flux upper limit, and m λ = 99 .
99 (as well as σ λ =99 .
99) indicates that no reliable photometric measurement could be obtained for that location. Forthe IRAC bands, δ λ = 99 .
99 implies that one or both of the associated photometric measurementsdid not yield a > σ flux measurement.Large mismatches between the two (PSF-fitting and aperture) measurements, specially when | δ λ | >> σ λ , are a good indicator of when crowding is significantly effecting the photometry and canbe useful as an alternative estimate of photometric uncertainty. While PSF-fitting photometry maybe generally preferable for crowded field photometry where possible, the δ λ values would let onerevert to using the aperture photometry measurements instead. Large δ λ values associated withseemingly bright sources are also indicative of contamination due to saturated foreground objectsbeing resolved into multiple bright sources by the PSF-fitting point source detection procedure(foreground giants would have m .
7, e.g., McQuinn et al. 2007). This is a major source of falsepositives, specially for M 31, as its large field of view contains numerous foreground objects. Indeed,our attempt to identify evolved dust-obscured very high-mass stars ( M ZAMS & M ⊙ ) in M 31following the selection criteria described in Khan et al. (2013) picked up many such spurious sourcesdue to their apparently peculiar spectral energy distributions (SEDs).
3. Discussion
Figure 1 shows the m . vs. m . − m . color magnitude diagram (CMD) for M 31 and Figure 2shows the same for the galaxies M 83, NGC 6946, M 101 and M 51 which have the highest SFR amongall the galaxies surveyed. The 1 σ color and magnitude uncertainties indicate that the horizontalextent of the CMDs are largely a result of color uncertainties. The blue-ward extent of the M 31CMD is consistent with, e.g, the comparable CMDs of M 33 shown on Fig. 14 of McQuinn et al.(2007) and Fig. 4 of Khan et al. (2015b), and it contains a larger fraction of blue sources than the15 galaxies beyond the local group cataloged here. As these galaxies are between factors of ∼ . . ∼
18 (NGC 3184 at 14 . .
78 Mpc), inM 31 we identify intrinsically fainter and lower mass stars with relatively bluer colors. These includeO- and C-rich Asymptotic Giant Branch (AGB) stars (e.g., Bolatto et al. 2007) and possibly someRed Giant Branch (RGB) stars ( m . .
18 in M 31, e.g., Blum et al. 2006; Boyer et al. 2015) as 5 –well as the more evolved and more luminous (massive) stars with warm circumstellar dust whichhave redder mid-IR colors (M 31 is known to have some young massive stars, e.g., Lewis et al. 2015;Massey et al. 2016).All normal stars have the same mid-IR color in the first two IRAC bands, because of theRayleigh-Jeans tails of their spectra, and we see this as a sequence of foreground dwarfs with m . − m . ≃ m . ≃ −
16. This feature is not as prominent on the M 31 CMD when compared to the tight streamof ex-AGB stars visible on the CMD of M 33, which has significantly higher ( & × ) specific starformation rate (e.g., see Lewis et al. 2015, for a detailed discussion of M 31’s recent star formationhistory) and thus a larger number of younger massive stars per unit stellar mass, although it is stilla prominent feature when compared to CMDs of even lower mass/SFR galaxies such as NGC 6822(see Fig. 4 of Khan et al. 2015b for M 33 and NGC 6822 mid-IR CMDs).However, quasars also have this color (e.g., Stern et al. 2005), as do star forming galaxies withstrong PAH emission at 8 . µ m (e.g., the SED models in Assef et al. 2010), and the ex-AGB starsare far less noticeable amid background contaminants on the more distant galaxy CMDs. Althoughthese galaxies have smaller effective survey areas and do not have more background contaminationper unit area than M 31, their greater distance modulus ( µ ) means that stars in those galaxieshave larger apparent magnitudes. As a result, the evolved stellar populations in those galaxiesare effectively buried among background sources on the CMDs. For example, the tip of the AGBbranch that is at m . ≃
13 on the M 31 CMD ( µ ≃ .
5, Figure 2) would be at at m . ≃
17 onthe M 83 CMD ( µ ≃ .
3, Figure 2). Given the rarity of ex-AGB stars (e.g., Thompson et al. 2009;Khan et al. 2010; Boyer et al. 2015) it is very likely that most of the very red ( m . − m . & region of the NOAO Bootes Field producedfrom the Spitzer
Deep Wide Field Survey (SDWFS, Ashby et al. 2009) data (dotted line). TheSDWFS catalog can be largely considered “empty” as in most sources being background galaxiesand quasars, with only a small fraction being foreground stars (e.g., see Koz lowski 2016). Figures 3shows that our catalogs are & m . & m . & m . &
17 and m . & . . µ m bands at least at a 3 σ level by PSF fitting. Any meaningfulstatistical test in this context therefore would also need to account for stellar SED variations in themid-IR to test multi-band catalog completeness for a particular region of interest.Figure 4 shows the mid-IR color histograms of all sources in the catalogs with 1 σ uncertaintyin color . .
2, following the same representation as Figure 3. As discussed earlier in this section,the m . − m . color distribution of M 31 is skewed blue-ward compared to the other galaxies. The m . − m . and m . − m . color distributions (middle row of Figure 4) of these more distant galaxiespeak at > . µ m flux maybe dominated by PAH emissions, which is a common feature of massive star-forming regions and starclusters (e.g., Churchwell et al. 2006) created by strong stochastic emission from PAH molecules(e.g., Whelan et al. 2011) excited by UV radiation from O- and B-type stars (see Wood et al. 2008for a detailed treatment of this topic). Their m . − m . , m . − m . and m . − m . colordistributions generally match those of the Bootes field but are redder than M 31 (bottom row ofFigure 4), consistent with significant extragalactic contamination (see Fig. 5 of Khan et al. 2015bfor mid-IR CMDs of the SDWFS sources).It is important to highlight here that the color histograms do not include sources for whichwe could only measure a flux upper-limits at the 5 . . µ m bands. Since the catalogslist sources that have > σ detections at the 3 . . µ m, the middle and bottom rows ofFigure 4 are inherently biased toward redder sources, i.e., those with > σ detections at the twolonger wavelength bands as well as the two shorter ones. This can exclude relatively bluer sourcessuch as foreground dwarfs as well as O- and C-rich AGB stars in the targeted galaxies that areintrinsically less luminous at the longer wavelengths. A more rigorous pursuit of this topic requiresstudying near-IR to mid-IR color separations of the cataloged sources, e.g., as done for the LMC 7 –by Blum et al. (2006) utilizing 2MASS data. However, 2MASS is not deep enough to study stellarpopulations in other galaxies (even M 31’s distance modulus is ∼ . − µ m bright point-source populations in crowded extragalactic fields and they are also an archive for studying futuremid-IR transients. The JWST’s Near-IR Spectrograph (NIRSpec, Dorner et al. 2016) and Mid-IR Instrument (MIRI, Rieke et al. 2015) will cover the ∼ − µ m and ∼ − µ m wavelengthranges respectively, but the JWST’s small field of view and anticipated over-subscription practicallymeans that these catalogs will continue to be the most detailed listing of mid-IR source propertiesin nearby galaxies in the near future. These 3 . − µ m point-source catalogs can be very useful toidentify scientifically interesting sources for photometric and spectroscopic follow-up with NIRSpecand MIRI in general. They create a pathway for the exploration of extragalactic evolved stellarpopulations as well as other mid-IR bright sources with the JWST and WFIRST, making optimaland efficient use of these flagship observatories.We thank the referee for helpful suggestions, Krzysztof Stanek, Christopher Kochanek andGeorge Sonneborn for productive discussions, and Martha Boyer and Karl Gordon for providingthe M 31 image mosaics. This work is based on observations made with the Spitzer
Space Telescope,which is operated by the Jet Propulsion Laboratory, California Institute of Technology under a con-tract with the National Aeronautics and Space Administration (NASA). We extend our gratitudeto the SINGS Legacy Survey and the LVL Survey for making their data publicly available. Thisresearch has made use of NED, which is operated by the JPL and Caltech, under contract withNASA and the HEASARC Online Service, provided by NASA’s GSFC. RK is supported througha JWST Fellowship hosted by the Goddard Space Flight Center and awarded as part of the NASAPostdoctoral Program operated by the Oak Ridge Associated Universities on behalf of NASA.
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This preprint was prepared with the AAS L A TEX macros v5.2.
10 –Table 1: Catalog Statistics
Galaxy Galactic coor. Distance Data SFR a Number longitude latitude (Mpc) reference
Source M ⊙ / year of SourcesM 31 121 . − .
573 0 .
78 Stanek & Garnavich (1998)
Note b . c , .
899 41 .
659 3 . d .
076 3 , . − .
643 4 . d .
316 6 , .
584 31 .
973 4 .
61 Saha et al. (2006) LVL d .
411 23 , .
363 76 .
007 4 .
66 Jacobs et al. (2009) SINGS e .
224 10 , .
680 84 .
423 4 .
66 Jacobs et al. (2009) SINGS e .
355 5 , .
487 41 .
376 5 .
45 Herrmann et al. (2008) LVL d .
524 4 , .
719 11 .
673 5 . e .
289 15 , .
301 22 .
933 6 Rozanski & Rowan-Robinson (1994) SINGS e .
115 991NGC 5457 102 .
037 59 .
771 6 .
43 Shappee & Stanek (2011) LVL d .
697 16 , . − .
672 6 . d .
245 4 , .
851 68 .
561 8 Ferrarese et al. (2000) SINGS e .
512 8 , .
711 44 .
540 8 .
55 Tully et al. (2009) LVL d .
932 5 , . − .
174 9 . e .
562 4 , .
961 64 .
418 10 . d .
022 3 , .
336 55 .
638 14 . e . . . 3 , a H α luminosity from Kennicutt et al. (2008)are converted to star formation rate (SFR) following Equation 2 ofKennicutt (1998). b IRAC 3 . − . µ m from (Barmby et al. 2006) and MIP 24 µ m from Gordon et al. (2006). c See Lewis et al. (2015) for a detailed discussion of M 31’s recent star formation history. d ocal Volume Legacy Survey (LVL, Dale et al. 2009). e Spitzer
Infrared Nearby Galaxies Survey (SINGS, Kennicutt et al. 2003).
11 –Fig. 1.— The m . vs. m . − m . color magnitude diagram (CMD) for the cataloged sources inM 31. The red lines represent isodensity contours, and the error bars show mean 1 σ color andmagnitude uncertainties for cataloged sources in 1 magnitude bins. 12 –Fig. 2.— Same as Figure 1 for the galaxies M 51, M 83, M 101 and NGC 6946. 13 –Fig. 3.— Apparent magnitude histograms for all cataloged sources in M 31 and in the other 15galaxies (shaded regions), with the latter scaled up for clarity by a factor of 3. The dotted linesshow the apparent-magnitude histograms of the SDWFS catalog sources, scaled up for clarity by afactor of 30 for m . and m . , and by a factor of 50 for m . and m . . 14 –Fig. 4.— Mid-IR color histograms for all cataloged sources in M 31 and in the other 15 galaxies(shaded regions) with 1 σ uncertainty in color . .
2, with the latter scaled up for clarity by factorsof 5 (first and second rows) and 2 (bottom row). The dotted lines show the mid-IR color histogramsof the SDWFS catalog sources, scaled-up for clarity by factors of 30 (first and second rows) and 15(bottom row).
Table 2: Catalog for 859 ,
165 Point Sources in M 31
RA Dec m . σ . δ . m . σ . δ . m . σ . δ . m . σ . δ . m σ (deg) (deg) (mag) (mag) (mag) (mag) (mag). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11 . . .
01 0 .
03 0 .
10 9 .
68 0 . − .
01 9 .
57 0 . − .
12 9 .
54 0 .
03 0 .
03 9 .
72 0 . . . .
46 0 .
13 0 .
83 9 .
69 0 .
08 1 .
02 6 .
79 0 .
01 99 .
99 9 .
53 0 .
16 2 .
45 6 .
18 0 . . . .
12 0 .
10 1 .
01 9 .
70 0 .
06 0 .
86 8 .
30 0 .
01 99 .
99 8 .
32 0 .
03 0 .
09 8 .
08 0 . . . .
00 0 .
04 0 .
06 9 .
71 0 . − .
01 9 .
65 0 . − .
05 9 .
89 0 .
06 0 .
21 9 .
71 0 . . . .
02 0 .
01 0 .
11 9 .
71 0 .
02 0 .
01 9 .
66 0 . − .
18 9 .
70 0 .
03 0 .
03 9 .
61 0 .
02. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 3: Catalog for 3 ,
794 Point Sources in NGC 3077
RA Dec m . σ . δ . m . σ . δ . m . σ . δ . m . σ . δ . m σ (deg) (deg) (mag) (mag) (mag) (mag) (mag). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .150 . . .
25 0 .
10 0 .
49 16 .
45 0 .
11 0 .
81 14 .
73 0 .
07 99 .
99 13 .
46 0 .
12 99 .
99 8 .
40 0 . . . .
28 0 . − .
04 16 .
45 0 .
07 0 .
15 16 .
52 0 . − .
07 15 .
47 0 . − .
57 99 .
99 99 . . . .
49 0 .
09 0 .
30 16 .
45 0 .
12 99 .
99 16 .
21 0 .
13 1 .
27 13 .
62 0 .
12 99 .
99 8 .
16 0 . . . .
13 0 .
07 0 .
47 16 .
45 0 .
06 0 .
17 16 .
21 0 . − .
55 15 .
79 0 . − .
87 12 .
87 0 . . . .
14 0 .
11 0 .
70 16 .
46 0 .
06 0 .
17 16 .
36 0 .
10 0 .
35 15 .
42 0 .
06 0 .
05 11 .
33 0 .
08. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 4: Catalog for 6 ,
972 Point Sources in NGC 1313
RA Dec m . σ . δ . m . σ . δ . m . σ . δ . m . σ . δ . m σ (deg) (deg) (mag) (mag) (mag) (mag) (mag). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .49 . − . .
55 0 .
05 0 .
00 15 .
60 0 .
06 0 .
01 15 .
65 0 .
05 0 .
23 15 .
80 0 .
04 0 .
11 12 .
13 0 . . − . .
60 0 .
12 0 .
13 15 .
60 0 . − .
03 14 .
38 0 .
08 99 .
99 13 .
28 0 .
07 99 .
99 8 .
47 0 . . − . .
41 0 .
13 0 .
08 15 .
60 0 . − .
00 14 .
82 0 .
04 0 .
30 13 .
92 0 .
06 0 .
74 8 .
44 0 . . − . .
43 0 .
06 0 .
18 15 .
61 0 .
05 0 .
07 14 .
91 0 .
02 0 .
16 13 .
72 0 .
05 0 .
39 11 .
58 99 . . − . .
52 0 .
04 0 .
01 15 .
61 0 .
05 0 .
10 14 .
88 0 .
05 0 .
54 14 .
04 0 .
08 1 .
28 8 .
42 0 .
07. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 5: Catalog for 10 ,
264 Point Sources in NGC 4736 (M 94)
RA Dec m . σ . δ . m . σ . δ . m . σ . δ . m . σ . δ . m σ (deg) (deg) (mag) (mag) (mag) (mag) (mag). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .192 . . .
65 0 .
09 0 .
78 15 .
11 0 .
11 0 .
46 13 .
03 0 .
13 0 .
80 12 .
19 0 .
14 1 .
80 6 .
20 0 . . . .
38 0 .
08 0 .
12 15 .
11 0 .
04 0 .
12 15 .
34 0 .
04 0 .
28 15 .
04 0 .
06 0 .
35 12 .
35 0 . . . .
13 0 .
06 0 .
15 15 .
11 0 .
03 0 .
05 14 .
38 0 . − .
00 13 .
50 0 .
03 0 .
07 9 .
87 0 . . . .
44 0 .
12 1 .
36 15 .
11 0 .
12 1 .
19 12 .
88 0 .
10 1 .
02 11 .
62 0 .
07 1 .
79 5 .
57 0 . . . .
14 0 .
09 1 .
11 15 .
12 0 .
08 1 .
24 15 .
07 0 .
09 1 .
64 12 .
09 0 .
08 0 .
99 8 .
28 0 .
01. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 6: Catalog for 5 ,
137 Point Sources in NGC 4826(M 64)
RA Dec m . σ . δ . m . σ . δ . m . σ . δ . m . σ . δ . m σ (deg) (deg) (mag) (mag) (mag) (mag) (mag). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .194 . . .
41 0 .
10 0 .
13 15 .
34 0 .
08 0 .
07 15 .
73 0 .
16 0 .
73 15 .
02 0 . − .
10 11 .
52 0 . . . .
50 0 .
05 0 .
04 15 .
35 0 . − .
16 14 .
36 0 . − .
04 12 .
90 0 . − .
14 9 .
68 0 . . . .
31 0 . − .
14 15 .
36 0 . − .
02 15 .
33 0 . − .
04 15 .
40 0 . − .
41 13 .
06 99 . . . .
37 0 .
13 99 .
99 15 .
37 0 .
13 99 .
99 13 .
62 0 .
10 0 .
59 11 .
61 0 .
09 0 .
49 6 .
93 0 . . . .
51 0 .
07 0 .
33 15 .
38 0 .
07 0 .
37 14 .
95 0 .
10 0 .
26 14 .
09 0 . − .
02 10 .
57 0 .
07. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 7: Catalog for 23 ,
331 Point Sources in NGC 5236 (M 83)
RA Dec m . σ . δ . m . σ . δ . m . σ . δ . m . σ . δ . m σ (deg) (deg) (mag) (mag) (mag) (mag) (mag). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .204 . − . .
49 0 . − .
03 13 .
54 0 . − .
01 13 .
49 0 . − .
05 13 .
57 0 .
05 0 .
25 11 .
95 99 . . − . .
50 0 . − .
03 13 .
55 0 . − .
01 13 .
52 0 . − .
01 13 .
55 0 . − .
05 11 .
89 99 . . − . .
75 0 .
06 0 .
05 13 .
55 0 . − .
08 13 .
64 0 .
02 0 .
01 13 .
89 0 .
04 0 .
03 12 .
31 99 . . − . .
09 0 .
09 0 .
93 13 .
55 0 .
08 0 .
75 10 .
94 0 .
05 0 .
77 8 .
38 0 .
03 99 .
99 4 .
18 0 . . − . .
57 0 . − .
01 13 .
56 0 . − .
05 13 .
15 0 .
05 0 .
18 12 .
74 0 .
09 0 .
95 9 .
07 99 .
99. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 8: Catalog for 5 ,
617 Point Sources in NGC 5068
RA Dec m . σ . δ . m . σ . δ . m . σ . δ . m . σ . δ . m σ (deg) (deg) (mag) (mag) (mag) (mag) (mag). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .199 . − . .
92 0 .
14 0 .
83 15 .
41 0 .
11 0 .
37 13 .
75 0 .
11 0 .
71 11 .
39 0 .
04 0 .
23 7 .
91 0 . . − . .
61 0 .
13 0 .
05 15 .
41 0 . − .
10 13 .
50 0 . − .
03 11 .
48 0 . − .
04 7 .
87 0 . . − . .
48 0 .
13 0 .
88 15 .
42 0 .
13 0 .
85 14 .
22 0 .
11 0 .
88 11 .
91 0 .
06 0 .
64 8 .
32 0 . . − . .
22 0 .
14 0 .
23 15 .
43 0 .
12 0 .
40 13 .
26 0 .
11 0 .
08 11 .
00 0 . − .
38 7 .
89 0 . . − . .
37 0 .
05 0 .
02 15 .
43 0 .
04 0 .
02 15 .
08 0 . − .
38 13 .
84 0 .
07 0 .
37 9 .
70 0 .
05. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 9: Catalog for 15 ,
813 Point Sources in NGC 6946
RA Dec m . σ . δ . m . σ . δ . m . σ . δ . m . σ . δ . m σ (deg) (deg) (mag) (mag) (mag) (mag) (mag). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .308 . . .
78 0 . − .
11 14 .
59 0 . − .
30 14 .
40 0 .
04 99 .
99 13 .
56 0 .
24 99 .
99 8 .
21 0 . . . .
44 0 . − .
02 14 .
60 0 .
14 0 .
13 14 .
36 0 . − .
02 14 .
42 0 .
15 0 .
06 99 .
99 99 . . . .
57 0 . − .
06 14 .
60 0 .
04 0 .
00 14 .
38 0 . − .
03 14 .
20 0 . − .
23 11 .
33 99 . . . .
80 0 .
14 0 .
93 14 .
60 0 .
10 1 .
15 12 .
19 0 .
10 1 .
13 11 .
01 0 .
12 1 .
71 5 .
14 0 . . . .
45 0 .
11 0 .
56 14 .
60 0 .
10 0 .
67 12 .
25 0 .
12 0 .
59 12 .
32 99 .
99 99 .
99 99 .
99 99 .
99. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 10: Catalog for 991 Point Sources in NGC 5474
RA Dec m . σ . δ . m . σ . δ . m . σ . δ . m . σ . δ . m σ (deg) (deg) (mag) (mag) (mag) (mag) (mag). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .211 . . .
02 0 .
05 0 .
06 17 .
17 0 . − .
19 16 .
70 0 .
11 99 .
99 16 .
18 0 .
12 0 .
49 11 .
28 0 . . . .
25 0 .
06 0 .
02 17 .
17 0 .
06 0 .
06 16 .
88 0 . − .
09 15 .
81 0 . − .
43 11 .
49 0 . . . .
05 0 .
16 1 .
14 17 .
18 0 .
13 0 .
80 16 .
08 0 .
09 0 .
49 14 .
49 0 .
07 0 .
42 10 .
31 0 . . . .
37 0 . − .
07 17 .
19 0 . − .
02 16 .
71 0 . − .
32 15 .
94 0 .
11 0 .
80 11 .
06 0 . . . .
28 0 . − .
03 17 .
21 0 .
13 0 .
45 17 .
16 0 . − .
25 16 .
12 0 .
23 0 .
22 12 .
94 0 .
27. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 11: Catalog for 16 ,
291 Point Sources in NGC 5457 (M 101)
RA Dec m . σ . δ . m . σ . δ . m . σ . δ . m . σ . δ . m σ (deg) (deg) (mag) (mag) (mag) (mag) (mag). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .210 . . .
36 0 .
09 0 .
01 14 .
33 0 .
07 0 .
01 14 .
38 0 . − .
43 14 .
72 0 .
09 99 .
99 11 .
05 99 . . . .
28 0 .
05 0 .
00 14 .
34 0 .
04 0 .
01 14 .
55 0 .
05 0 .
10 14 .
25 0 .
05 0 .
06 11 .
79 0 . . . .
48 0 .
10 0 .
62 14 .
35 0 .
14 0 .
90 11 .
57 0 .
06 0 .
57 9 .
73 0 .
02 0 .
51 5 .
45 0 . . . .
77 0 .
09 0 .
43 14 .
35 0 .
06 0 .
38 12 .
01 0 .
07 0 .
51 10 .
21 0 .
03 0 .
58 5 .
41 0 . . . .
12 0 . − .
07 14 .
35 0 .
06 0 .
12 14 .
33 0 .
06 0 .
07 14 .
15 0 . − .
06 12 .
01 0 .
29. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 12: Catalog for 4 ,
321 Point Sources in NGC 45
RA Dec m . σ . δ . m . σ . δ . m . σ . δ . m . σ . δ . m σ (deg) (deg) (mag) (mag) (mag) (mag) (mag). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3 . − . .
84 0 .
06 0 .
31 15 .
96 0 .
09 0 .
77 15 .
71 0 .
17 0 .
61 14 .
63 0 .
05 0 .
76 10 .
74 0 . . − . .
25 0 .
07 0 .
10 15 .
96 0 .
13 0 .
39 15 .
29 0 . − .
18 12 .
62 0 .
03 0 .
13 9 .
38 0 . . − . .
11 0 .
08 0 .
22 15 .
96 0 .
05 0 .
35 16 .
26 0 .
07 0 .
68 15 .
41 0 .
06 0 .
70 11 .
39 0 . . − . .
34 0 .
07 0 .
19 15 .
97 0 .
09 0 .
10 16 .
12 0 .
09 0 .
09 15 .
33 0 . − .
22 11 .
63 0 . . − . .
05 0 .
04 0 .
10 15 .
97 0 . − .
00 16 .
33 0 .
11 0 .
53 15 .
10 0 .
09 99 .
99 11 .
59 99 .
99. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 13: Catalog for 8 ,
601 Point Sources in NGC 5194 (M 51)
RA Dec m . σ . δ . m . σ . δ . m . σ . δ . m . σ . δ . m σ (deg) (deg) (mag) (mag) (mag) (mag) (mag). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .202 . . .
32 0 .
11 0 .
68 13 .
58 0 . − .
01 13 .
43 0 .
08 0 .
02 13 .
61 0 .
05 0 .
50 11 .
08 0 . . . .
53 0 .
14 0 .
59 13 .
58 0 . − .
09 12 .
37 0 . − .
19 11 .
49 0 .
07 0 .
96 6 .
96 0 . . . .
27 0 . − .
19 13 .
59 0 . − .
82 11 .
41 0 .
09 0 .
04 9 .
61 0 .
08 0 .
11 5 .
43 0 . . . .
19 0 .
09 0 .
39 13 .
59 0 .
05 0 .
04 13 .
08 0 .
11 1 .
11 10 .
32 0 . − .
13 4 .
76 0 . . . .
03 0 .
13 0 .
57 13 .
64 0 .
06 0 .
66 11 .
39 0 .
11 0 .
71 9 .
82 0 .
06 0 .
96 4 .
65 0 .
03. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 14: Catalog for 5 ,
579 Point Sources in NGC 2903
RA Dec m . σ . δ . m . σ . δ . m . σ . δ . m . σ . δ . m σ (deg) (deg) (mag) (mag) (mag) (mag) (mag). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .143 . . .
79 0 .
09 0 .
78 14 .
53 0 .
12 0 .
56 11 .
80 0 .
10 0 .
46 9 .
94 0 .
03 0 .
45 6 .
05 0 . . . .
47 0 . − .
00 14 .
53 0 .
06 0 .
03 14 .
61 0 . − .
01 14 .
41 0 . − .
35 11 .
75 0 . . . .
85 0 .
11 0 .
34 14 .
53 0 .
13 0 .
11 12 .
76 0 .
10 0 .
10 10 .
68 0 .
06 0 .
04 7 .
46 0 . . . .
49 0 . − .
02 14 .
54 0 . − .
02 14 .
80 0 .
09 0 .
01 14 .
12 0 . − .
45 12 .
26 99 . . . .
60 0 .
10 99 .
99 14 .
54 0 .
12 99 .
99 15 .
95 0 .
13 0 .
67 14 .
35 0 .
05 99 .
99 11 .
30 99 .
99. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 15: Catalog for 4 ,
217 Point Sources in NGC 925
RA Dec m . σ . δ . m . σ . δ . m . σ . δ . m . σ . δ . m σ (deg) (deg) (mag) (mag) (mag) (mag) (mag). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36 . . .
73 0 . − .
01 15 .
67 0 . − .
01 15 .
66 0 . − .
25 15 .
39 0 . − .
85 11 .
90 0 . . . .
99 0 .
09 1 .
12 15 .
67 0 .
12 1 .
00 15 .
64 0 .
07 0 .
93 14 .
38 0 .
06 1 .
40 10 .
47 0 . . . .
79 0 .
11 0 .
28 15 .
68 0 .
13 0 .
48 14 .
56 0 .
14 1 .
16 12 .
45 0 .
10 0 .
72 7 .
79 0 . . . .
63 0 .
06 0 .
00 15 .
68 0 .
09 0 .
00 15 .
94 0 . − .
42 15 .
12 0 . − .
56 99 .
99 99 . . . .
93 0 .
05 0 .
15 15 .
68 0 .
09 0 .
10 15 .
61 0 . − .
01 14 .
26 0 . − .
02 11 .
85 0 .
12. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 16: Catalog for 3 ,
102 Point Sources in NGC 3627
RA Dec m . σ . δ . m . σ . δ . m . σ . δ . m . σ . δ . m σ (deg) (deg) (mag) (mag) (mag) (mag) (mag). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .170 . . .
40 0 .
04 0 .
09 13 .
75 0 .
10 0 .
09 13 .
03 0 .
06 0 .
03 12 .
14 0 . − .
03 8 .
28 0 . . . .
79 0 . − .
09 13 .
76 0 .
13 0 .
15 11 .
11 0 .
11 0 .
02 9 .
52 0 .
10 0 .
21 4 .
51 0 . . . .
03 0 .
13 1 .
36 13 .
76 0 .
12 1 .
54 11 .
51 0 .
13 1 .
71 9 .
79 0 .
08 1 .
85 3 .
68 0 . . . .
89 0 . − .
02 13 .
80 0 . − .
05 13 .
86 0 .
05 0 .
10 13 .
61 0 . − .
21 13 .
06 99 . . . .
12 0 .
10 0 .
15 13 .
81 0 .
12 0 .
24 11 .
63 0 .
08 99 .
99 9 .
71 0 .
08 99 .
99 4 .
78 0 .
09. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 17: Catalog for 3 ,
548 Point Sources in NGC 3184
RA Dec m . σ . δ . m . σ . δ . m . σ . δ . m . σ . δ . m σ (deg) (deg) (mag) (mag) (mag) (mag) (mag). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .154 . . .
82 0 .
10 0 .
22 16 .
13 0 .
06 0 .
13 15 .
70 0 .
06 0 .
04 14 .
37 0 . − .
14 10 .
91 0 . . . .
35 0 .
09 0 .
19 16 .
13 0 .
04 0 .
10 16 .
29 0 .
07 0 .
46 15 .
34 0 . − .
50 12 .
46 99 . . . .
47 0 .
12 0 .
29 16 .
14 0 .
09 0 .
21 15 .
76 0 .
09 0 .
33 14 .
63 0 . − .
22 99 .
99 99 . . . .
09 0 .
12 0 .
39 16 .
15 0 .
12 0 .
71 13 .
72 0 .
11 0 .
87 11 .
16 0 .
03 0 .
32 7 .
93 0 . . . .
75 0 .
15 1 .
08 16 .
15 0 .
08 0 .
79 15 .
20 0 .
19 99 .
99 14 .
70 0 .
27 0 .
02 99 .
99 99 ..