J/ApJS/193/31 M33 Chandra ACIS survey: final catalog (Tullmann+, 2011)
The Chandra ACIS survey of M33 (ChASeM33): the final source catalog.
Tullmann R., Gaetz T.J., Plucinsky P.P., Kuntz K.D., Williams B.F.,
Pietsch W., Haberl F., Long K.S., Blair W.P., Sasaki M., Winkler P.F.,
Challis P., Pannuti T.G., Edgar R.J., Helfand D.J., Hughes J.P.,
Kirshner R.P., Mazeh T., Shporer A.
<Astrophys. J. Suppl. Ser., 193, 31 (2011)>
=2011ApJS..193...31T 2011ApJS..193...31T
ADC_Keywords: Binaries, X-ray ; Galaxies, nearby ; Cross identifications ;
Surveys
Keywords: binaries: general - galaxies: individual (M33) -
ISM: supernova remnants - surveys - X-rays: galaxies
Abstract:
This study presents the final source catalog of the Chandra ACIS
Survey of M33 (ChASeM33). With a total exposure time of 1.4Ms,
ChASeM33 covers ∼70% of the D25 isophote (R∼4.0kpc) of M33 and
provides the deepest, most complete, and detailed look at a spiral
galaxy in X-rays. The source catalog includes 662 sources, reaches a
limiting unabsorbed luminosity of ∼2.4x1034erg/s in the 0.35-8.0keV
energy band, and contains source positions, source net counts, fluxes
and significances in several energy bands, and information on source
variability. To constrain the nature of the detected X-ray source,
hardness ratios were constructed and spectra were fit for 254 sources,
follow-up MMT spectra of 116 sources were acquired, and
cross-correlations with previous X-ray catalogs and other
multi-wavelength data were generated. Based on this effort, 183 of the
662 ChASeM33 sources could be identified. Finally, the luminosity
function (LF) for the detected point sources as well as the one for
the X-ray binaries (XRBs) in M33 is presented. The resulting
distribution is consistent with a dominant population of high-mass
XRBs as would be expected for M33.
Description:
The results presented here use the full survey data obtained during
2005 September to 2006 November. All observations were performed with
ACIS-I as the primary instrument.
In addition to the ChASeM33 observations, we also utilized two
archival ACIS-I observations of M33 (ObsIDs 1730 and 2023) obtained
in 2000 July 12 and 2001 July 6.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 81 662 ChASeM33 source list
table4.dat 75 662 Merged pns values for different energy bands
table5.dat 167 662 Total net counts in the counts in different
energy bands
table6.dat 81 662 Merged photon flux in different energy bands
table7.dat 155 254 Best-fit results for sources with 8 or more
spectral groups
table9.dat 156 662 Cross-referenced source list
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See also:
B/chandra : The Chandra Archive Log (CXC, 1999-)
J/ApJS/187/495 : SNRs in M33 from optical and X-ray (Long+, 2010)
J/ApJS/174/366 : Chandra ACIS survey of M33 (ChaSeM33) (Plucinsky+, 2008)
J/A+A/448/1247 : XMM-Newton survey of M33 (Misanovic+, 2006)
J/AJ/131/2478 : M31 and M33 UBVRI photometry (Massey+, 2006)
J/ApJS/161/271 : The X-ray binary population in M33. I (Grimm+, 2005)
J/A+A/426/11 : XMM-Newton survey of M33 (Pietsch+, 2004)
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 Source number
5- 22 A18 --- Name Source identifier (HHMMSS.ss+DDMMSS.s; J2000)
24- 32 F9.6 deg RAdeg Right Ascension in decimal degrees (J2000)
34- 41 F8.5 deg DEdeg Declination in decimal degrees (J2000)
43- 46 F4.2 arcsec ePos Positional error
48- 49 I2 --- Nobs Number of observations
51- 56 I6 s Exp Total exposure in all observations
58- 66 E9.3 s.cm2 Expmap Total exposure map value (1)
68- 71 F4.1 pix Rsrc Average source radius in sky pixels (2)
73- 76 F4.1 pix Rbkg Average background radius in sky pixels (2)
78- 81 F4.1 arcmin theta Average off-axis angle
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Note (1): Sum of mean exposure map values in source region for all observations.
Note (2): 1 sky pixel = 0.492".
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- Seq Source number
5 A1 --- l_pns1 Limit flag on pns1
6- 12 E7.1 --- pns1 Poisson probability of not being
a source in the 0.5-8.0keV energy band (1)
14 A1 --- l_pns2 Limit flag on pns2
15- 21 E7.1 --- pns2 Poisson probability of not being
a source in the 0.5-2.0keV energy band (1)
23 A1 --- l_pns3 Limit flag on pns3
24- 30 E7.1 --- pns3 Poisson probability of not being
a source in the 2.0-8.0keV energy band (1)
32 A1 --- l_pns4 Limit flag on pns4
33- 39 E7.1 --- pns4 Poisson probability of not being
a source in the 0.35-8.0keV energy band (1)
41 A1 --- l_pns5 Limit flag on pns5
42- 48 E7.1 --- pns5 Poisson probability of not being
a source in the 0.35-1.1keV energy band (1)
50 A1 --- l_pns6 Limit flag on pns6
51- 57 E7.1 --- pns6 Poisson probability of not being
a source in the 1.1-2.6keV energy band (1)
59 A1 --- l_pns7 Limit flag on pns7
60- 66 E7.1 --- pns7 Poisson probability of not being
a source in the 2.6-8.0keV energy band (1)
68 A1 --- l_pns8 Limit flag on pns8
69- 75 E7.1 --- pns8 Poisson probability of not being
a source in the 0.35-2.0keV energy band (1)
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Note (1): pns values smaller than 1.0e-10 have been replaced by <1.0e-10.
All these cases are highly significant detections.
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- Seq Source number
5- 12 F8.1 ct Ncts1 Total net counts in the 0.5-8.0keV energy band
14- 18 F5.1 ct E_Ncts1 The upper 90% confidence level in Ncts1
20- 24 F5.1 ct e_Ncts1 The lower 90% confidence level in Ncts1
26- 33 F8.1 ct Ncts2 Total net counts in the 0.5-2.0keV energy band
35- 39 F5.1 ct E_Ncts2 The upper 90% confidence level in Ncts2
41- 45 F5.1 ct e_Ncts2 The lower 90% confidence level in Ncts2
47- 53 F7.1 ct Ncts3 Total net counts in the 2.0-8.0keV energy band
55- 59 F5.1 ct E_Ncts3 The upper 90% confidence level in Ncts3
61- 65 F5.1 ct e_Ncts3 The lower 90% confidence level in Ncts3
67- 74 F8.1 ct Ncts4 Total net counts in the 0.35-8.0keV energy band
76- 80 F5.1 ct E_Ncts4 The upper 90% confidence level in Ncts4
82- 86 F5.1 ct e_Ncts4 The lower 90% confidence level in Ncts4
88- 94 F7.1 ct Ncts5 Total net counts in the 0.35-1.1keV energy band
96-100 F5.1 ct E_Ncts5 The upper 90% confidence level in Ncts5
102-106 F5.1 ct e_Ncts5 The lower 90% confidence level in Ncts5
108-114 F7.1 ct Ncts6 Total net counts in the 1.1-2.6keV energy band
116-120 F5.1 ct E_Ncts6 The upper 90% confidence level in Ncts6
122-126 F5.1 ct e_Ncts6 The lower 90% confidence level in Ncts6
128-134 F7.1 ct Ncts7 Total net counts in the 2.6-8.0keV energy band
136-140 F5.1 ct E_Ncts7 The upper 90% confidence level in Ncts7
142-146 F5.1 ct e_Ncts7 The lower 90% confidence level in Ncts7
148-155 F8.1 ct Ncts8 Total net counts in the 0.35-2.0keV energy band
157-161 F5.1 ct E_Ncts8 The upper 90% confidence level in Ncts8
163-167 F5.1 ct e_Ncts8 The lower 90% confidence level in Ncts8
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Byte-by-byte Description of file: table6.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- Seq Source number
5- 12 A8 ph/cm2/s F1 Photon flux in the 0.5-8.0keV energy band
14- 22 E9.2 ph/cm2/s F2 Photon flux in the 0.5-2.0keV energy band
24- 32 E9.2 ph/cm2/s F3 Photon flux in the 2.0-8.0keV energy band
34- 41 A8 ph/cm2/s F4 Photon flux in the 0.35-8.0keV energy band
43- 51 E9.2 ph/cm2/s F5 Photon flux in the 0.35-1.1keV energy band
53- 61 E9.2 ph/cm2/s F6 Photon flux in the 1.1-2.6keV energy band
63- 71 E9.2 ph/cm2/s F7 Photon flux in the 2.6-8.0keV energy band
73- 81 E9.2 ph/cm2/s F8 Photon flux in the 0.35-2.0keV energy band
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Byte-by-byte Description of file: table7.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- Seq Source number
5- 22 A18 --- Name Source identifier (HHMMSS.ss+DDMMSS.s; J2000)
24- 28 A5 --- Model Best-fit model (1)
30- 33 F4.2 10+22/cm2 NH Internal column density (2)
35- 38 F4.2 10+22/cm2 E_NH The upper 90% confidence level in NH
40- 43 F4.2 10+22/cm2 e_NH The lower 90% confidence level in NN
45- 49 F5.2 --- Gamma ? Spectral index
51- 54 F4.2 --- e_Gamma ? The upper 90% confidence level in Gamma
56- 59 F4.2 --- E_Gamma ? The lower 90% confidence level in Gamma
61- 65 F5.2 keV kT ? Plasma temperature
67- 71 F5.2 keV E_kT ? The lower 90% confidence level in kT
73- 76 F4.2 keV e_kT ? The upper 90% confidence level in kT
78- 85 E8.2 --- Norm Normalization constant of the fit (3)
87- 94 E8.2 --- E_Norm The upper 90% confidence level in Norm
96-103 E8.2 --- e_Norm The lower 90% confidence level in Norm
105-107 I3 --- dof Degrees of freedom
109-112 F4.2 --- chi2 Reduced χ2
114-120 F7.2 10+28W LX1 The 0.35-2keV luminosity; 1035erg/s (4)
122-126 F5.2 10+28W E_LX1 The upper 90% confidence level in LX1
128-133 F6.2 10+28W e_LX1 The lower 90% confidence level in LX1
135-142 F8.2 10+28W LX2 The 0.35-8keV luminosity; 1035erg/s (4)
144-148 F5.2 10+28W E_LX2 The upper 90% confidence level in LX2
150-155 F6.2 10+28W e_LX2 The lower 90% confidence level in LX2
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Note (1): The best-fit model is either a powerlaw or a vapec model, depending
which one has the lower χ2red.
Note (2): The Galactic NH was fixed at 0.06e22cm-2 (Dickey & Lockman,
1990ARA&A..28..215D 1990ARA&A..28..215D).
Note (3): For the powerlaw and the vapec model, the units are
photons/keV/cm2/s at 1keV and cm-5, respectively.
Note (4): Absorption-corrected X-ray luminosities assume a distance to M 33
of D=817kpc (Freedman et al. 2001ApJ...553...47F 2001ApJ...553...47F).
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Byte-by-byte Description of file: table9.dat
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Bytes Format Units Label Explanations
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1- 18 A18 --- Name Source identifier (HHMMSS.ss+DDMMSS.s)
20- 22 I3 --- Seq Source number (1)
24- 26 I3 --- FLC ? ChASeM33 First Look Catalog number;
Cat. J/ApJS/174/366
28- 30 I3 --- P04 ? XMM number in Pietsch et al. 2004,
Cat. J/A+A/426/11 (2)
32- 34 I3 --- M06 ? XMM number in Misanovic et al. 2006,
Cat. J/A+A/448/1247 (2)
36- 38 I3 --- G05 ? Chandra source number in Grimm et al.
2005, Cat. J/ApJS/161/271
40 I1 --- Ext [0,2] Extended (>0) source code (3)
42- 45 F4.1 --- eta ? The 5σ variability index (4)
47 A1 --- f_eta [b] highly likely to show long-term
variability
49 A1 --- l_xi Limit flag on xi
50- 57 E8.2 --- xi ? KS probability of constant source (5)
59 A1 --- f_xi [b] highly likely to show short-term
variablility.
61- 65 F5.1 --- Frat ? Ratio of max to min X-ray fluxes
67- 73 F7.1 --- e_Frat ? The 1σ uncertainty in FRatio
75- 82 F8.3 10-20W/m2/arcsec2 SHa ? Hα surface brightness (6)
84-126 A43 --- OType Source type (7)
128-156 A29 --- Comm Additional comment(s)
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Note (1): Number 151 and 152 have been inverted compared with table 3.
Corrected at CDS. Idem for number 173 and 174, 186 and 187,
315 and 316, 426 and 427.
Note (2): Designations are <[PMH2004] NNN> in Simbad for P04 and
<[MPH2006] NNN> in Simbad for M06.
Note (3): Code as follows:
2 = possibly extended;
1 = extended;
0 = not extended.
Note (4): eta is sensitive to long-term variability. Sources with
variability indices of η≥5.0 are highly likely to show
long-term variability.
Note (5): Within a single observation (short-term variability). Sources
with KS probabilities of ξ≤5.7e-7 are highly likely to show
short-term variablility (see section 3.4).
Note (6): In units of 1e-17erg/s/cm2/arcsec2. Measured from LGGS
survey data (Massey et al. 2006, Cat. J/AJ/131/2478) and extracted
from circular regions with a radius of 2". Empty entries indicate that
the source either did not lie inside the central LGGS field or is
coincident with a foreground star. Any values
<5e-17erg/s/cm2/arcsec2 are probably consistent with zero.
Note (7): Source classification and aliases using the USNO-B1.0 catalog
Monet et al. (2003, Cat. I/284) and the 2MASS catalog Cutri et al.
(2003, Cat. II/246). We discern the following types of sources:
(a) foreground stars (FS), (b) stellar sources in M 33, (c) galaxies,
(d) QSOs/AGN, (e) non-stellar sources, (f) SNRs (labeled 'L10-XXX'),
(g) XRBs, and (h) transient sources (labeled 'XRT'). For the
transients and the SNRs we use data from the ChASeM33 transient search
Williams et al. (2008ApJ...680.1120W 2008ApJ...680.1120W, <[WGH2008] XRT-N> in Simbad) as
well as from the ChASeM33 SNR catalog: Long et al. (2010, Cat.
J/ApJS/187/495). The classification of classes (a)-(e) is based on MMT
follow-up spectroscopy and multi-wavelength data (see section 3.2).
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History:
From electronic version of the journal
References:
Plucinsky et al. ChASeM33: first look. 2008ApJS..174..366P 2008ApJS..174..366P Cat. J/ApJS/174/366
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 19-May-2011