J/A+A/480/599 XMM-Newton survey of M31 centre field (Stiele+, 2008)
Time variability of X-ray sources in the M31 centre field.
Stiele H., Pietsch W., Haberl F., Freyberg M.
<Astron. Astrophys. 480, 599 (2008)>
=2008A&A...480..599S 2008A&A...480..599S
ADC_Keywords: Galaxies, nearby ; X-ray sources
Keywords: galaxies: individual: M31 - X-rays: galaxies
Abstract:
We present an extension to our XMM-Newton X-ray source catalogue of
M 31, containing 39 newly found sources. In order to classify and
identify more of the sources we search for X-ray time variability
in XMM-Newton archival data the M31 centre field.
As source list we use our extended catalogue based on observations
covering the time span from June 2000 to July 2004. We then determine
the flux or at least an upper limit at the source positions for each
observation. Deriving the flux ratios for the different observations
and searching for the maximum flux difference we determine variability
factors. We also calculated the significance of the flux ratios.
Using hardness ratios, X-ray variability and cross correlations with
catalogues in the X-ray, optical, infrared and radio regimes, we
detected three super soft source candidates, one supernova remnant
and six supernova remnant candidates, one globular cluster candidate,
three X-ray binaries and four X-ray binary candidates. Additionally
we identified one foreground star candidate and classified fifteen
sources with hard spectra, which may either be X-ray binaries or
Crab-like supernova remnants in M31 or background active galactic
nuclei. The remaining five sources stay unidentified or without
classification. Based on the time variability results we suggest six
sources, which were former classified as "hard", to be X-ray binary
candidates. The classification of one source (XMMM31 J004236.7+411349)
as supernova remnant, has to be rejected due to the distinct time
variability we found. We now classify this source as a foreground
star.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 696 39 X-ray source catalogue extension of the
XMM-Newton EPIC M31 central observations
table5.dat 978 300 X-ray variability of the central sources in M31
detected in XMM-Newton EPIC observations
refs.dat 138 52 References
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See also:
J/A+A/426/11 : XMM-Newton survey of the Local Group galaxy M 33 (Pietsch+ 2004)
J/A+A/434/483 : An XMM-Newton survey of M31 (Pietsch+ 2005)
Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- Seq [857/895] Source number (1)
5- 10 A6 --- M31ID M31 field identification
11- 12 I2 h RAh Right Ascension J2000 (hours)
14- 15 I2 min RAm Right Ascension J2000 (minutes)
17- 21 F5.2 s RAs Right Ascension J2000 (seconds)
24 A1 --- DE- Declination J2000 (sign)
25- 26 I2 deg DEd Declination J2000 (degrees)
28- 29 I2 arcmin DEm Declination J2000 (minutes)
31- 34 F4.1 arcsec DEs Declination J2000 (seconds)
36- 40 F5.2 arcsec e_Pos ? Positional error (2)
42- 49 E8.2 --- LH Source detection likelihood
(combined EPIC)
51- 58 E8.2 ct/s CRate Combined EPIC count rate (G2)
60- 66 E7.1 ct/s e_CRate Error in CRate
68- 75 E8.2 mW/m2 CFlux Combined EPIC flux in erg/cm2/s (G2)
77- 83 E7.1 mW/m2 e_CFlux Error in CFlux
85- 89 F5.2 --- CHR1 ? Combined EPIC hardness ratio 1 (G3)
91- 96 F6.2 --- e_CHR1 ? Error in CHR1
98-102 F5.2 --- CHR2 ? Combined EPIC hardness ratio 2 (G3)
104-109 F6.2 --- e_CHR2 ? Error in CHR2
111-115 F5.2 --- CHR3 ? Combined EPIC hardness ratio 3 (G3)
117-120 F4.2 --- e_CHR3 ? Error in CHR3
122-126 F5.2 --- CHR4 ? Combined EPIC hardness ratio 4 (G3)
128-131 F4.2 --- e_CHR4 ? Error in CHR4
133-135 A3 --- VAL EPIC instruments contributing to source
detection (G4)
137-141 F5.1 ks PNExpo ? Exposure of EPIC pn instrument
143-150 E8.2 --- PNLH ? EPIC pn source detection likelihood
152-159 E8.2 ct/s PNRate ? EPIC pn count rate (G2)
161-167 E7.1 ct/s e_PNRate ? Error in PNRate
169-176 E8.2 mW/m2 PNFlux ? EPIC pn flux in erg/cm2/s (G2)
178-184 E7.1 mW/m2 e_PNFlux ? Error in PNFlux
186-190 F5.2 --- PNHR1 ? EPIC pn hardness ratio 1 (G3)
192-197 F6.2 --- e_PNHR1 ? Error in PNHR1
199-203 F5.2 --- PNHR2 ? EPIC pn hardness ratio 2 (G3)
205-208 F4.2 --- e_PNHR2 ? Error in PNHR2
210-214 F5.2 --- PNHR3 ? EPIC pn hardness ratio 3 (G3)
216-219 F4.2 --- e_PNHR3 ? Error in PNHR3
221-225 F5.2 --- PNHR4 ? EPIC pn hardness ratio 4 (G3)
227-230 F4.2 --- e_PNHR4 ? Error in PNHR4
232-236 F5.1 ks M1Expo ? Exposure of EPIC MOS1 instrument
238-245 E8.2 --- M1LH ? EPIC MOS1 source detection likelihood
247-254 E8.2 ct/s M1Rate ? EPIC MOS1 count rate (G2)
256-262 E7.1 ct/s e_M1Rate ? Error in M1Rate
264-271 E8.2 mW/m2 M1Flux ? EPIC MOS1 flux in erg/cm2/s (G2)
273-279 E7.1 mW/m2 e_M1Flux ? Error in M1Flux
281-285 F5.2 --- M1HR1 ? EPIC MOS1 hardness ratio 1 (G3)
287-290 F4.2 --- e_M1HR1 ? Error in M1HR1
292-296 F5.2 --- M1HR2 ? EPIC MOS1 hardness ratio 2 (G3)
298-301 F4.2 --- e_M1HR2 ? Error in M1HR2
303-307 F5.2 --- M1HR3 ? EPIC MOS1 hardness ratio 3 (G3)
309-312 F4.2 --- e_M1HR3 ? Error in M1HR3
314-318 F5.2 --- M1HR4 ? EPIC MOS1 hardness ratio 4 (G3)
320-323 F4.2 --- e_M1HR4 ? Error in M1HR4
325-329 F5.1 ks M2Expo ? Exposure of EPIC MOS2 instrument
331-338 E8.2 --- M2LH ? EPIC MOS2 source detection likelihood
340-347 E8.2 ct/s M2Rate ? EPIC MOS2 count rate (G2)
349-355 E7.1 ct/s e_M2Rate ? Error in M2Rate
357-364 E8.2 mW/m2 M2Flux ? EPIC MOS2 flux in erg/cm2/s (G2)
366-372 E7.1 mW/m2 e_M2Flux ? Error in M2Flux
374-378 F5.2 --- M2HR1 ? EPIC MOS2 hardness ratio 1 (G3)
380-383 F4.2 --- e_M2HR1 ? Error in M2HR1
385-389 F5.2 --- M2HR2 ? EPIC MOS2 hardness ratio 2 (G3)
391-394 F4.2 --- e_M2HR2 ? Error in M2HR2
396-400 F5.2 --- M2HR3 ? EPIC MOS2 hardness ratio 3 (G3)
402-405 F4.2 --- e_M2HR3 ? Error in M2HR3
407-411 F5.2 --- M2HR4 ? EPIC MOS2 hardness ratio 4 (G3)
413-416 F4.2 --- e_M2HR4 ? Error in M2HR4
418-517 A100 --- XID ? X-ray identification (G5)
518-529 A12 --- USNOB1.0 ? Name of brightest USNO-B1.0
source within search area
531 I1 --- USNOMul ? Number of USNO-B1.0 correlations
533-535 F3.1 arcsec USNOdist ? Distance of source USNO-B1.0
537-540 F4.1 mag USNOB2 ? B2 magnitude of source USNO-B1.0
542-545 F4.1 mag USNOR2 ? R2 magnitude of source USNO-B1.0
547-550 F4.1 mag USNOI ? I magnitude of source USNO-B1.0
552-555 F4.1 --- log(fX/fopt) ? Logarithm of fX/fopt
557-571 A15 --- Class ? Classification of X-ray source (G6)
573-672 A100 --- Remarks ? Additional remarks, in refs.dat files
674-679 A6 --- --- [XMMM31]
681-696 A16 --- XMMM31 Source Name XMMM31 (Jhhmmss.s+ddmmss)
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Note (1): The numbering is a continuation of Pietsch et al., 2005,
Cat. J/A+A/434/483, [PFH2005] NNN in Simbad)
Note (2): 1σ statistical error, 0.5" to be added as 1σ
systematic error
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- SRCID [136/891] Source Number (1)
5- 12 E8.3 mW/m2 CFlux Combined EPIC flux in erg/cm2/s (G2)
14- 20 E7.2 mW/m2 e_CFlux Error in CFlux
22- 26 F5.2 --- CHR1 ? Combined EPIC hardness ratio 1 (G3)
28- 33 F6.2 --- e_CHR1 ? Error in CHR1
35- 39 F5.2 --- CHR2 ? Combined EPIC hardness ratio 2 (G3)
41- 46 F6.2 --- e_CHR2 ? Error in CHR2
48- 52 F5.2 --- CHR3 ? Combined EPIC hardness ratio 3 (G3)
54- 57 F4.2 --- e_CHR3 ? Error in CHR3
59- 63 F5.2 --- CHR4 ? Combined EPIC hardness ratio 4 (G3)
65- 68 F4.2 --- e_CHR4 ? Error in CHR4
70-225 A156 --- XID ? X-ray identification (G5)
227-241 A15 --- Class ? Classification of X-ray source (G6)
243-342 A100 --- Remarks ? Additional remarks, in refs.dat file
344-346 A3 --- c1val ? EPIC instruments contributing to source
detection in observation c1 (G4)
348-355 E8.3 ct/s c1Rate ? EPIC count rate in observation c1 (G2)
357-363 E7.2 ct/s e_c1Rate ? Error in c1Rate
365-372 E8.3 mW/m2 c1Flux ? EPIC flux in erg/cm2/s in observation c1 (G2)
374-380 E7.2 mW/m2 e_c1Flux ? Error in c1Flux
382-386 F5.2 --- c1HR1 ? EPIC hardness ratio 1 in observation c1 (G3)
388-391 F4.2 --- e_c1HR1 ? Error in c1HR1
393-397 F5.2 --- c1HR2 ? EPIC hardness ratio 2 in observation c1 (G3)
399-402 F4.2 --- e_c1HR2 ? Error in c1HR2
404-408 F5.2 --- c1HR3 ? EPIC hardness ratio 3 in observation c1 (G3)
410-413 F4.2 --- e_c1HR3 ? Error in c1HR3
415-419 F5.2 --- c1HR4 ? EPIC hardness ratio 4 in observation c1 (G3)
421-424 F4.2 --- e_c1HR4 ? Error in c1HR4
426-428 A3 --- c2val ? EPIC instruments contributing to source
detection in observation c2 (G4)
430-437 E8.3 ct/s c2Rate ? EPIC count rate in observation c2 (G2)
439-445 E7.2 ct/s e_c2Rate ? Error in c2Rate
447-454 E8.3 mW/m2 c2Flux ? EPIC flux in erg/cm2/s in observation c2 (G2)
456-462 E7.2 mW/m2 e_c2Flux ? Error in c2Flux
464-468 F5.2 --- c2HR1 ? EPIC hardness ratio 1 in observation c2 (G3)
470-473 F4.2 --- e_c2HR1 ? Error in c2HR1
475-479 F5.2 --- c2HR2 ? EPIC hardness ratio 2 in observation c2 (G3)
481-484 F4.2 --- e_c2HR2 ? Error in c2HR2
486-490 F5.2 --- c2HR3 ? EPIC hardness ratio 3 in observation c2 (G3)
492-497 F6.2 --- e_c2HR3 ? Error in c2HR3
499-503 F5.2 --- c2HR4 ? EPIC hardness ratio 4 in observation c2 (G3)
505-508 F4.2 --- e_c2HR4 ? Error in c2HR4
510-512 A3 --- c3val ? EPIC instruments contributing to source
detection in observation c3 (G4)
514-521 E8.3 ct/s c3Rate ? EPIC count rate in observation c3 (G2)
523-529 E7.2 ct/s e_c3Rate ? Error in c3Rate
531-538 E8.3 mW/m2 c3Flux ? EPIC flux in erg/cm2/s in observation c3 (G2)
540-546 E7.2 mW/m2 e_c3Flux ? Error in c3Flux
548-552 F5.2 --- c3HR1 ? EPIC hardness ratio 1 in observation c3 (G3)
554-557 F4.2 --- e_c3HR1 ? Error in c3HR1
559-563 F5.2 --- c3HR2 ? EPIC hardness ratio 2 in observation c3 (G3)
565-568 F4.2 --- e_c3HR2 ? Error in c3HR2
570-574 F5.2 --- c3HR3 ? EPIC hardness ratio 3 in observation c3 (G3)
576-581 F6.2 --- e_c3HR3 ? Error in c3HR3
583-587 F5.2 --- c3HR4 ? EPIC hardness ratio 4 in observation c3 (G3)
589-592 F4.2 --- e_c3HR4 ? Error in c3HR4
594-596 A3 --- n1val ? EPIC instruments contributing to source
detection in observation n1 (G4)
598-605 E8.3 ct/s n1Rate ? EPIC count rate in observation n1 (G2)
607-613 E7.2 ct/s e_n1Rate ? Error in n1Rate
615-622 E8.3 mW/m2 n1Flux ? EPIC flux in erg/cm2/s in observation n1 (G2)
624-630 E7.2 mW/m2 e_n1Flux ? Error in n1Flux
632-636 F5.2 --- n1HR1 ? EPIC hardness ratio 1 in observation n1 (G3)
638-641 F4.2 --- e_n1HR1 ? Error in n1HR1
643-647 F5.2 --- n1HR2 ? EPIC hardness ratio 2 in observation n1 (G3)
649-652 F4.2 --- e_n1HR2 ? Error in n1HR2
654-658 F5.2 --- n1HR3 ? EPIC hardness ratio 3 in observation n1 (G3)
660-663 F4.2 --- e_n1HR3 ? Error in n1HR3
665-669 F5.2 --- n1HR4 ? EPIC hardness ratio 4 in observation n1 (G3)
671-674 F4.2 --- e_n1HR4 ? Error in n1HR4
676-678 A3 --- c4val ? EPIC instruments contributing to source
detection in observation c4 (G4)
680-687 E8.3 ct/s c4Rate ? EPIC count rate in observation c4 (G2)
689-695 E7.2 ct/s e_c4Rate ? Error in c4Rate
697-704 E8.3 mW/m2 c4Flux ? EPIC flux in erg/cm2/s in observation c4 (G2)
706-712 E7.2 mW/m2 e_c4Flux ? Error in c4Flux
714-718 F5.2 --- c4HR1 ? EPIC hardness ratio 1 in observation c4 (G3)
720-723 F4.2 --- e_c4HR1 ? Error in c4HR1
725-729 F5.2 --- c4HR2 ? EPIC hardness ratio 2 in observation c4 (G3)
731-734 F4.2 --- e_c4HR2 ? Error in c4HR2
736-740 F5.2 --- c4HR3 ? EPIC hardness ratio 3 in observation c4 (G3)
742-745 F4.2 --- e_c4HR3 ? Error in c4HR3
747-751 F5.2 --- c4HR4 ? EPIC hardness ratio 4 in observation c4 (G3)
753-756 F4.2 --- e_c4HR4 ? Error in c4HR4
758-760 A3 --- s1val ? EPIC instruments contributing to source
detection in observation s1 (G4)
762-769 E8.3 ct/s s1Rate ? EPIC count rate in observation s1 (G2)
771-777 E7.2 ct/s e_s1Rate ? Error in s1Rate
779-786 E8.3 mW/m2 s1Flux ? EPIC flux in erg/cm2/s in observation s1 (G2)
788-794 E7.2 mW/m2 e_s1Flux ? Error in s1Flux
796-800 F5.2 --- s1HR1 ? EPIC hardness ratio 1 in observation s1 (G3)
802-805 F4.2 --- e_s1HR1 ? Error in s1HR1
807-811 F5.2 --- s1HR2 ? EPIC hardness ratio 2 in observation s1 (G3)
813-816 F4.2 --- e_s1HR2 ? Error in s1HR2
818-822 F5.2 --- s1HR3 ? EPIC hardness ratio 3 in observation s1 (G3)
824-827 F4.2 --- e_s1HR3 ? Error in s1HR3
829-833 F5.2 --- s1HR4 ? EPIC hardness ratio 4 in observation s1 (G3)
835-838 F4.2 --- e_s1HR4 ? Error in s1HR4
840-842 A3 --- bval ? EPIC instruments contributing to source
detection in observation b (G4)
844-851 E8.3 ct/s bRate ? EPIC count rate in observation b (G2)
853-859 E7.2 ct/s e_bRate ? Error in bRate
861-868 E8.3 mW/m2 bFlux ? EPIC flux in erg/cm2/s in observation b (G2)
870-876 E7.2 mW/m2 e_bFlux ? Error in bFlux
878-882 F5.2 --- bHR1 ? EPIC hardness ratio 1 in observation b (G3)
884-887 F4.2 --- e_bHR1 ? Error in bHR1
889-893 F5.2 --- bHR2 ? EPIC hardness ratio 2 in observation b (G3)
895-898 F4.2 --- e_bHR2 ? Error in bHR2
900-904 F5.2 --- bHR3 ? EPIC hardness ratio 3 in observation b (G3)
906-909 F4.2 --- e_bHR3 ? Error in bHR3
911-915 F5.2 --- bHR4 ? EPIC hardness ratio 4 in observation b (G3)
917-920 F4.2 --- e_bHR4 ? Error in bHR4
922 I1 --- ndet Number of observations covering the source
924-928 F5.2 --- svarmax Maximum of significance of variation
930-935 F6.2 --- fvarmax Maximum of flux ratio
937 I1 --- nupper Number of upper limits
939-946 E8.3 mW/m2 fmax ? Maximum flux
948-954 E7.2 mW/m2 e_fmax ? Error in fmax
956-961 A6 --- --- [XMMM31]
963-978 A16 --- XMMM31 Source Name XMMM31 (Jhhmmss.s+ddmmss)
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Note (1): For numbers 136 to 856, source number from Table 2 in Pietsch et
al., 2005, Cat. J/A+A/434/483, [PFH2005] NNN in Simbad.
For numbers 857 to 891, source number of Table 3 in this paper
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Byte-by-byte Description of file: refs.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- Ref Reference code
10- 28 A19 --- BibCode BibCode
30- 56 A27 --- Name Author's name
58-138 A81 --- Com Comments
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Global notes:
Note (G2):
Count rate and flux in XID band (0.2-4.5keV)
Note (G3): HRi=(R(i+1)-R(i))/(R(i+1)+R(i)) where Ri are the count rates
in the energy bands 1 to 5, with
band 1 = 0.2-0.5keV,
band 2 = 0.5-1.0keV,
band 3 = 1.0-2.0keV,
band 4 = 2.0-4.5keV,
band 5 = 4.5-12keV
Note (G4): First character for EPIC PN, second for MOS1,
third for MOS2 with meaning
T = source is in field of view of instrument
F = otherwise
Note (G5): References in XID are coded as follows:
TF91 = Trinchieri et al., 1991ApJ...382...82T 1991ApJ...382...82T
CRP90 = Collura et al., 1990ApJ...356..119C 1990ApJ...356..119C
PFJ93 = Primini et al., 1993ApJ...410..615P 1993ApJ...410..615P
SHP97 = Supper et al., 1997A&A...317..328S 1997A&A...317..328S
CXOGMP Jhhmmss.s+ddmmss = Garcia et al., 2000ApJ...537L..23G 2000ApJ...537L..23G
SHL2001 = Supper et al., 2001A&A...373...63S 2001A&A...373...63S
OBT2001 = Osborne et al., 2001A&A...378..800O 2001A&A...378..800O
am-n = Kong et al., 2002ApJ...577..738K 2002ApJ...577..738K
= Di Stefano et al., 2004ApJ...610..247D 2004ApJ...610..247D
= Williams et al., 2004ApJ...609..735W 2004ApJ...609..735W
= Williams et al., 2006ApJ...637..479W 2006ApJ...637..479W
= Williams et al., 2005ApJ...632.1086W 2005ApJ...632.1086W
DKG2002 = Di Stefano et al., 2002ApJ...570..618D 2002ApJ...570..618D
Jhhmmss.s+ddmmss = Kaaret, 2002ApJ...578..114K 2002ApJ...578..114K
= Di Stefano et al., 2002ApJ...570..618D 2002ApJ...570..618D
= Trudolyubov et al., 2006ApJ...645..277T 2006ApJ...645..277T
TKP2004 = Trudolyubov et al., 2005ApJ...634..314T 2005ApJ...634..314T
PHS2007 = Pietsch et al., 2007A&A...465..375P 2007A&A...465..375P
FMZ2005 = Fan et al., 2005PASP...117.1236F
VG2007 = Voss et al., 2007A&A...468...49V 2007A&A...468...49V
XMMU Jhhmmss.s+ddmmss = Trudolyubov et al., 2006ApJ...645..277T 2006ApJ...645..277T
TPC2006b = Trudolyubov et al., 2006astro.ph.10809T 2006astro.ph.10809T
Note (G6): Classifications used (see Table 2) as follows:
fg Star = foreground star
= foreground star candidate
AGN = active galactic nucleus
= AGN candidate
GAL = galaxy
GCl = galaxy cluster
<GCl> = galaxy cluster candidate
SSS = supersoft source in M31
= supersoft source candidate in M31
SNR = supernova remnant in M31
= supernova remnant candidate in M31
GlC = source in globular cluster
<GlC> = source in globular cluster candidate
XRB = X-ray binary in M31
= X-ray binary candidate in M31
= HR2-e_HR2>-0.2 or only HR3 and HR4 defined, and no other
classification
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History:
Holger Stiele, hstiele(at)mpe.mpg.de
(End) Holger Stiele [MPE, Germany], Patricia Vannier [CDS] 14-Feb-2008