J/ApJS/239/13 Chandra PHAT X-ray catalog of the M31 disk (Williams+, 2018)
Comparing Chandra and Hubble in the northern disk of M31.
Williams B.F., Lazzarini M., Plucinsky P.P., Sasaki M., Antoniou V.,
Vulic N., Eracleous M., Long K.S., Binder B., Dalcanton J.J., Lewis A.R.,
Weisz D.R.
<Astrophys. J. Suppl. Ser., 239, 13-13 (2018)>
=2018ApJS..239...13W 2018ApJS..239...13W (SIMBAD/NED BibCode)
ADC_Keywords: Galaxies, nearby; X-ray sources; Cross identifications; Optical
Keywords: galaxies: individual: M31; stars: massive; X-rays: binaries;
X-rays: galaxies
Abstract:
The X-ray source populations within galaxies are typically difficult
to identify and classify with X-ray data alone. We are able to break
through this barrier by combining deep new Chandra ACIS-I observations
with extensive Hubble Space Telescope (HST) imaging from the
Panchromatic Hubble Andromeda Treasury of the M31 disk. We detect 373
X-ray sources down to 0.35-8.0keV flux of 10-15erg/cm-2/s over
0.4deg2, 170 of which are reported for the first time. We identify
optical counterpart candidates for 188 of the 373 sources, after using
the HST data to correct the absolute astrometry of our Chandra imaging
to 0.1". While 58 of these 188 are associated with point sources
potentially in M31, over half (107) of the counterpart candidates are
extended background galaxies, 5 are star clusters, 12 are foreground
stars, and 6 are supernova remnants. Sources with no clear counterpart
candidate are most likely to be undetected background galaxies and
low-mass X-ray binaries in M31. The hardest sources in the 1-8keV band
tend to be matched to background galaxies. The 58 point sources that
are not consistent with foreground stars are bright enough that they
could be high-mass stars in M31; however, all but 8 have optical
colors inconsistent with single stars, suggesting that many could be
background galaxies or binary counterparts. For point-like
counterparts, we examine the star formation history of the surrounding
stellar populations to look for a young component that could be
associated with a high-mass X-ray binary. About one-third of the point
sources are not physically associated with a young population, and are
therefore more likely to be background galaxies. For the 40 point-like
counterpart candidates associated with young populations, we find that
their age distribution has two peaks at 15-20Myr and 40-50Myr. If we
only consider the 8 counterpart candidates with typical high-mass
main-sequence optical star colors, their age distribution peaks mimic
those of the sample of 40. Finally, we find that intrinsic faintness,
and not extinction, is the main limitation for finding further
counterpart candidates.
Description:
In 2015 October, we observed the Panchromatic Hubble Andromeda
Treasury (PHAT) footprint with Chandra with 7 pointings. The
footprints are overlaid on a GALEX NUV image of M31, along with the
corresponding HST coverage, in Figure 1. At each pointing we observed
for about 50ks in VF mode (Chandra ObsID 17008 to 17014 spanning 2015
Oct 06 to 2015 Oct 26).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table4.dat 751 373 Chandra PHAT X-ray catalog
table6.dat 125 57 PHAT point source counterpart candidate
multiwavelength properties
table7.dat 47 520 Best high-mass X-ray binary (HMXB) candidate
age probabilities
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See also:
B/chandra : The Chandra Archive Log (CXC, 1999-2014)
J/A+A/620/A28 : XMM northern disc of M31 sources (Sasaki+, 2018)
J/ApJ/846/145 : PHAT. XIX. Formation history of M31 disk (Williams+, 2017)
J/ApJS/228/2 : Chandra Deep Field-South survey: 7Ms sources (Luo+, 2017)
J/MNRAS/461/3443 : M31 deepest Chandra catalog of point sources (Vulic+, 2016)
J/AJ/150/94 : Chandra Local Volume Survey. I. (Binder+, 2015)
J/ApJ/802/127 : PHAT stellar cluster survey. II. AP catalog (Johnson+, 2015)
J/other/Ser/189.15 : Point source catalogue of M31. DR2 (Galvin+, 2014)
J/ApJS/215/9 : PHAT X. UV-IR photometry of M31 stars (Williams+, 2014)
J/ApJ/786/130 : Catalog of M31 SNR candidates (Lee+, 2014)
J/ApJ/763/128 : Chandra Local Volume Survey: NGC 404 sources (Binder+, 2013)
J/ApJ/758/15 : Chandra X-ray point sources of NGC 300 (Binder+, 2012)
J/A+A/534/A55 : Deep XMM-Newton Survey of M31 (Stiele+, 2011)
J/ApJS/193/31 : M33 Chandra ACIS survey: final catalog (Tullmann+, 2011)
J/A+A/495/733 : XMM-Newton spectral survey of M31 disc (Shaw+, 2009)
J/A+A/451/835 : Properties of X-ray sources in M31/M33 (Hatzidimitriou+, 2006)
J/A+A/434/483 : An XMM-Newton survey of M 31 (Pietsch+, 2005)
J/ApJ/610/247 : M31 supersoft and quasi-soft X-ray sources (Di Stefano+, 2004)
J/ApJ/609/735 : M31 Chandra X-ray sources (Williams+, 2004)
J/ApJS/150/19 : ChaMP. I. First X-ray source catalog (Kim+, 2004)
J/ApJ/578/114 : Chandra HRC source in M31 (Kaaret, 2002)
J/ApJ/577/738 : M31 Chandra X-ray point sources (Kong+, 2002)
J/A+A/373/63 : M31 second ROSAT PSPC survey (Supper+, 2001)
J/A+A/317/328 : ROSAT PSPC survey of M 31 (Supper+ 1997)
Byte-by-byte Description of file: table4.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- Seq Source number in this catalog
5- 9 I5 --- ObsID [17008/17014] Observation in which source
was measured
11- 28 A18 --- CXO Unique source identifier
(HHMMSS.ss+DDMMSS.s; J2000)
30- 38 F9.6 deg RAdeg [10.8/11.8] Right Ascension (J2000)
40- 48 F9.6 deg DEdeg [41.2/42.3] Declination (J2000)
50- 53 F4.2 arcsec PosErr [0.2/5] X-ray position uncertainty
55- 60 F6.3 arcmin Theta [0.4/12.1] Off-axis angle in Chandra
observation
62- 68 F7.1 ct C0.35-8.0 [1/15000] Source Net Counts
in 0.35-8.0keV band
70- 74 F5.1 ct e_C0.35-8.0 [1/130] Negative uncertainty in C0.35-8.0 (1)
76- 80 F5.1 ct E_C0.35-8.0 Positive uncertainty in C0.35-8.0
82- 89 F8.4 ct C0.35-1.0 [-2/910] Source Net Counts in 0.35-1.0keV band
91- 95 F5.2 ct e_C0.35-1.0 [0.8/99] Negative uncertainty in C0.35-1.0 (1)
97-100 F4.1 ct E_C0.35-1.0 Positive uncertainty in C0.35-1.0
102-108 F7.1 ct C0.5-8.0 [1/15000] Source Net Counts in 0.5-8.0keV band
110-114 F5.1 ct e_C0.5-8.0 [1/120] Negative uncertainty in C0.5-8.0 (1)
116-120 F5.1 ct E_C0.5-8.0 Positive uncertainty in C0.5-8.0
122-129 F8.4 ct C0.5-1.0 [-2/880] Source Net Counts in 0.5-1.0keV band
131-135 F5.2 ct e_C0.5-1.0 [0.8/99] Negative uncertainty in C0.5-1.0 (1)
137-140 F4.1 ct E_C0.5-1.0 Positive uncertainty in C0.5-1.0
142-149 F8.3 ct C1.0-2.0 [-1/6600] Source Net Counts in 1.0-2.0keV band
151-155 F5.2 ct e_C1.0-2.0 [0.8/99] Negative uncertainty in C1.0-2.0 (1)
157-160 F4.1 ct E_C1.0-2.0 Positive uncertainty in C1.0-2.0
162-169 F8.3 ct C2.0-4.0 [-1/5000] Source Net Counts in 2.0-4.0keV band
171-175 F5.2 ct e_C2.0-4.0 [0.8/99] Negative uncertainty in C2.0-4.0 (1)
177-180 F4.1 ct E_C2.0-4.0 Positive uncertainty in C2.0-4.0
182-189 F8.3 ct C2.0-8.0 [-3/7600] Source Net Counts in 2.0-8.0keV band
191-195 F5.2 ct e_C2.0-8.0 [0.8/99] Negative uncertainty in C2.0-8.0 (1)
197-200 F4.1 ct E_C2.0-8.0 Positive uncertainty in C2.0-8.0
202-209 F8.3 ct C4.0-8.0 [-2/2700] Source Net Counts in 4.0-8.0keV band
211-215 F5.2 ct e_C4.0-8.0 [0.8/99] Negative uncertainty in C4.0-8.0 (1)
217-220 F4.1 ct E_C4.0-8.0 Positive uncertainty in C4.0-8.0
222-228 E7.1 ct/s R0.35-8.0 [4.6e-05/0.3] ARF-corrected Count Rate
in 0.35-8.0keV band
230-236 E7.1 ct/s e_R0.35-8.0 Negative uncertainty in R0.35-8.0
238-244 E7.1 ct/s E_R0.35-8.0 Positive uncertainty in R0.35-8.0
246-253 E8.1 ct/s R0.35-1.0 ARF-corrected Count Rate in 0.35-2.0 keV band
255-261 E7.1 ct/s e_R0.35-1.0 [5.3e-05/99] Negative uncertainty
in R0.35-1.0 (1)
263-269 E7.1 ct/s E_R0.35-1.0 Positive uncertainty in R0.35-1.0
271-277 E7.1 ct/s R0.5-8.0 ARF-corrected Count Rate in 0.5-8.0 keV band
279-285 E7.1 ct/s e_R0.5-8.0 Negative uncertainty in R0.5-8.0
287-293 E7.1 ct/s E_R0.5-8.0 Positive uncertainty in R0.5-8.0
295-302 E8.1 ct/s R0.5-1.0 ARF-corrected Count Rate in 0.5-1.0 keV band
304-310 E7.1 ct/s e_R0.5-1.0 [4.7e-05/99] Negative uncertainty
in R0.5-1.0 (1)
312-318 E7.1 ct/s E_R0.5-1.0 Positive uncertainty in R0.5-1.0
320-327 E8.1 ct/s R1.0-2.0 ARF-corrected Count Rate in 1.0-2.0 keV band
329-335 E7.1 ct/s e_R1.0-2.0 [1.5e-05/99] Negative uncertainty
in R1.0-2.0 (1)
337-343 E7.1 ct/s E_R1.0-2.0 Positive uncertainty in R1.0-2.0
345-352 E8.1 ct/s R2.0-4.0 ARF-corrected Count Rate in 2.0-4.0 keV band
354-360 E7.1 ct/s e_R2.0-4.0 [1.8e-05/99] Negative uncertainty
in R2.0-4.0 (1)
362-368 E7.1 ct/s E_R2.0-4.0 Positive uncertainty in R2.0-4.0
370-377 E8.1 ct/s R2.0-8.0 ARF-corrected Count Rate in 2.0-8.0 keV band
379-385 E7.1 ct/s e_R2.0-8.0 [2.3e-05/99] Negative uncertainty
in R2.0-8.0 (1)
387-393 E7.1 ct/s E_R2.0-8.0 Positive uncertainty in R2.0-8.0
395-402 E8.1 ct/s R4.0-8.0 ARF-corrected Count Rate in 4.0-8.0 keV band
404-410 E7.1 ct/s e_R4.0-8.0 [1.7e-05/99] Negative uncertainty
in R4.0-8.0 (1)
412-418 E7.1 ct/s E_R4.0-8.0 Positive uncertainty in R4.0-8.0
420-426 E7.1 % PNS [0/0.01] Probability no source detected at
this location in 0.35-8.0keV band
428-434 E7.1 mW/m2 F0.35-8.0 Energy flux in 0.35-8.0 keV band (2)
436-442 E7.1 mW/m2 e_F0.35-8.0 Negative uncertainty in F0.35-8.0
444-450 E7.1 mW/m2 E_F0.35-8.0 Positive uncertainty in F0.35-8.0
452-459 E8.1 mW/m2 F0.35-1.0 Energy flux in 0.35-1.0 keV band (2)
461-467 E7.1 mW/m2 e_F0.35-1.0 [9.4e-16/99] Negative uncertainty
in F0.35-1.0 (1)
469-475 E7.1 mW/m2 E_F0.35-1.0 Positive uncertainty in F0.35-1.0
477-483 E7.1 mW/m2 F0.5-8.0 Energy flux in 0.5-8.0 keV band (2)
485-491 E7.1 mW/m2 e_F0.5-8.0 Negative uncertainty in F0.5-8.0
493-499 E7.1 mW/m2 E_F0.5-8.0 Positive uncertainty in F0.5-8.0
501-508 E8.1 mW/m2 F0.5-1.0 Energy flux in 0.5-1.0 keV band (2)
510-516 E7.1 mW/m2 e_F0.5-1.0 [6.7e-16/99] Negative uncertainty
in F0.5-1.0 (1)
518-524 E7.1 mW/m2 E_F0.5-1.0 Positive uncertainty in F0.5-1.0
526-533 E8.1 mW/m2 F1.0-2.0 Energy flux in 1.0-2.0 keV band (2)
535-541 E7.1 mW/m2 e_F1.0-2.0 [8.3e-17/99] Negative uncertainty
in F1.0-2.0 (1)
543-549 E7.1 mW/m2 E_F1.0-2.0 Positive uncertainty in F1.0-2.0
551-558 E8.1 mW/m2 F2.0-4.0 Energy flux in 2.0-4.0 keV band (2)
560-566 E7.1 mW/m2 e_F2.0-4.0 [2.6e-16/99] Negative uncertainty
in F2.0-4.0 (1)
568-574 E7.1 mW/m2 E_F2.0-4.0 Positive uncertainty in F2.0-4.0
576-583 E8.1 mW/m2 F2.0-8.0 Energy flux in 2.0-8.0 keV band (2)
585-591 E7.1 mW/m2 e_F2.0-8.0 [5e-16/99] Negative uncertainty
in F2.0-8.0 (1)
593-599 E7.1 mW/m2 E_F2.0-8.0 Positive uncertainty in F2.0-8.0
601-608 E8.1 mW/m2 F4.0-8.0 Energy flux in 4.0-8.0 keV band (2)
610-616 E7.1 mW/m2 e_F4.0-8.0 [5.8e-16/99] Negative uncertainty
in F4.0-8.0 (1)
618-624 E7.1 mW/m2 E_F4.0-8.0 Positive uncertainty in F4.0-8.0
626-632 E7.1 mW/m2 F0.2-4.5 Energy Flux in 0.2-4.5 keV band (2)
634-638 E5.0 mW/m2 e_F0.2-4.5 Negative uncertainty in F0.2-4.5
640-644 E5.0 mW/m2 E_F0.2-4.5 Positive uncertainty in F0.2-4.5
646-649 I4 --- [SPH2011] [1197/1881]? Matched source identifier in S11
(Stiele+ 2011, J/A+A/534/A55)
651-659 A9 --- Class Source classification
in Stiele+ 2011, J/A+A/534/A55
661 A1 --- PHAT Single letter PHAT counterpart code (3)
663-666 F4.2 mag Av [0.02/3.9]? Mean extinction from maps of
Dalcanton+ (2015ApJ...814....3D 2015ApJ...814....3D)
668-751 A84 --- Notes Notes from visual inspection of PHAT images
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Note (1): When the negative uncertainty is equal to 99 it indicates that this
is an upper-limit measurement.
Note (2): In erg/cm2/s.
0.35-8.0keV energy flux = (Count Rate * 1.313e-11);
0.35-1.0keV energy flux = (Count Rate * 1.767e-11);
0.5-8.0keV energy flux = (Count Rate * 1.272e-11);
0.5-1.0keV energy flux = (Count Rate * 1.438e-10);
1.0-2.0keV energy flux = (Count Rate * 5.620e-12);
2.0-4.0keV energy flux = (Count Rate * 1.443e-11);
2.0-8.0keV energy flux = (Count Rate * 2.138e-11);
4.0-8.0keV energy flux = (Count Rate * 3.487e-11);
0.2-4.5keV energy flux = (0.35-8.0keV Count Rate * 9.416e-12).
Note (3): Code as follows:
n = none (185 occurrences);
g = galaxy (107 occurrences);
p = point/star (58 occurrences);
f = foreground (12 occurrences);
s = SNR (6 occurrences);
c = cluster (5 occurrences).
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Byte-by-byte Description of file: table6.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 18 A18 --- CXO Unique source identifier
(HHMMSS.ss+DDMMSS.s; J2000)
20 A1 --- f_CXO Flag on CXO (1)
22- 30 F9.6 deg RAXdeg [10.9/11.8] CXO right ascension (J2000)
32- 40 F9.6 deg DEXdeg [41.2/42.3] CXO declination (J2000)
42- 45 F4.2 arcsec ePos [0.2/4.6] X-ray source position uncertainty
from Table 4
47- 55 F9.6 deg RAdeg [10.9/11.8] PHAT right ascension (J2000)
57- 65 F9.6 deg DEdeg [41.2/42.3] PHAT declination (J2000)
67- 72 F6.3 mag F275W [18.6/27.5]?=99.999 HST//WFC3 F275W band
magnitude
74- 78 F5.2 mag F336W [19/25.2] HST/WFC3 F336W band magnitude
80- 85 F6.3 mag F475W [20.2/26.2]?=99.999 HST/ACS F475W band
magnitude
87- 91 F5.2 mag F814W [17.3/24.6] HST/ACS F814W band magnitude
93- 98 F6.3 mag F110W [16.2/25.8]?=99.999 HST/WFC3 F110W band
magnitude
100-105 F6.3 mag F160W [15.4/25.5]?=99.999 HST/WFC3 F160W band
magnitude
107-113 E7.2 mW/m2 F0.35-8 [1.8e-15/1.3e-13] Flux in 0.35-8keV band
115-119 E5.1 mW/m2 e_F0.35-8 F0.35-8 negative uncertainty
121-125 E5.1 mW/m2 E_F0.35-8 F0.35-8 positive uncertainty
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Note (1): Flag as follows:
a = Included in the "best candidate" sample. CXO J004339.06+412117.6 is
considered such a candidate, but no SFH is available.
c = No local young population detected.
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Byte-by-byte Description of file: table7.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 18 A18 --- CXO Catalog identifier (HHMMSS.ss+DDMMSS.s; J2000)
19 A1 --- --- [,]
21- 24 F4.1 Myr LowAge [4/63.1] Lower edge of the age bin (1)
26- 29 F4.1 Myr HighAge [5/79.4] Higher edge of the age bin (1)
31- 35 F5.3 --- Prob [0/1] Probability HMXB system is in the age bin
37- 41 F5.3 --- E_Prob Positive uncertainty in Prob
43- 47 F5.3 --- e_Prob Negative uncertainty in Prob
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Note (1): For example, if low age is 4.0 and high age is 5.0, then the Prob
column refers to the probability that the HMXB candidate has an age
between 4.0 and 5.0Myr.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 20-Dec-2018