J/ApJS/174/366 Chandra ACIS survey of M33 (ChaSeM33) (Plucinsky+, 2008)
Chandra ACIS survey of M33 (ChASeM33): a first look.
Plucinsky P.P., Williams B., Long K.S., Gaetz T.J., Sasaki M., Pietsch W.,
Tullmann R., Smith R.K., Blair W.P., Helfand D., Hughes J.P., Winkler P.F.,
De Avillez M., Bianchi L., Breitschwerdt D., Edgar R.J., Ghavamian P.,
Grindlay J., Haberl F., Kirshner R., Kuntz K., Mazeh T., Pannuti T.G.,
Shporer A., Thilker D.A.
<Astrophys. J. Suppl. Ser., 174, 366-378 (2008)>
=2008ApJS..174..366P 2008ApJS..174..366P
ADC_Keywords: Cross identifications ; Supernova remnants ; X-ray sources
Keywords: galaxies: individual (M33) - supernova remnants - X-rays: galaxies
Abstract:
We present an overview of the Chandra ACIS Survey of M33 (ChASeM33):
A Deep Survey of the Nearest Face-on Spiral Galaxy. The 1.4Ms survey
covers the galaxy out to R∼18'(∼4kpc). These data provide the most
intensive, high spatial resolution assessment of the X-ray source
populations available for the confused inner regions of M33. The
initial source catalog, arising from ∼2/3 of the expected survey data,
includes 394 sources significant at the 3σ confidence level or
greater, down to a limiting luminosity (absorbed) of ∼1.6x1035ergs/s
(0.35-8.0keV). The hardness ratios of the sources separate those with
soft, thermal spectra such as supernova remnants from those with hard,
nonthermal spectra such as X-ray binaries and background active
galactic nuclei. Emission extended beyond the Chandra point-spread
function is evident in 23 of the 394 sources. Cross-correlation of
the ChASeM33 sources against previous catalogs of X-ray sources in M33
results in matches for the vast majority of the brighter sources and
shows 28 ChASeM33 sources within 10" of supernova remnants identified
by prior optical and radio searches. This brings the total number of
such associations to 31 out of 100 known supernova remnants in M33.
Description:
Our program was designed to comprise two long (∼100ks each)
uninterrupted observations of seven overlapping ACIS-I fields,
separated by 6 months or more. ChASeM33 observations began in 2005
September; in this paper we present the observations performed in the
first year of observations (i.e., through 2006 August).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 89 394 ChASeM33 X-ray Sources
table3.dat 88 258 Catalog Correlations
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See also:
B/chandra : The Chandra Archive Log (CXC, 1999- )
J/ApJS/120/247 : Supernova remnants in M33 (Gordon+, 1999)
/A+A/373/438 : X-ray view of M33 after ROSAT (Haberl+, 2001)
J/A+A/426/11 : XMM-Newton survey of M33 (Pietsch+, 2004)
J/A+A/448/1247 : XMM-Newton survey of M33 (Misanovic+, 2006)
J/A+A/451/835 : Properties of X-ray sources in M31/M33 (Hatzidimitriou+, 2006)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- ChASeM33 ChASeM33 source number
5 A1 --- n_ChASeM33 [E-] "E" for Extended source
7- 8 I2 h RAh Right Ascension J2000 (hours)
10- 11 I2 min RAm Right Ascension J2000 (minutes)
13- 17 F5.2 s RAs Right Ascension J2000 (seconds)
19 A1 --- DE- Declination J2000 (sign)
21- 22 I2 deg DEd Declination J2000 (degrees)
24- 25 I2 arcmin DEm Declination J2000 (minutes)
27- 30 F4.1 arcsec DEs Declination J2000 (seconds)
32- 35 F4.2 arcsec e_Pos Position Error (arcsec)
37- 44 F8.1 ct NetCts Net Counts from source (ct)
46- 51 F6.1 10-4ct/s CRate Count Rate in the 0.35-8.0keV band (1)
53- 56 F4.1 10-4ct/s e_CRate Error in CRate
58- 63 F6.1 10-6ph/cm2/s Flux Flux in the 0.35-8.0keV band (1)(2)
65- 67 F3.1 10-6ph/cm2/s e_Flux Error in Flux
69- 73 F5.2 --- HR1 Hardness Ratio 1 (1)(3)
75- 78 F4.2 --- e_HR1 Error in Hardness Ratio 1
80- 84 F5.2 --- HR2 Hardness Ratio 2 (1)(3)
86- 89 F4.2 --- e_HR2 Error in Hardness Ratio 2
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Note (1): Pileup affects the derived values for Rate, Photon Flux, and HRs.
These values should be treated with caution for the bright sources.
Note (2): Absorbed photon flux (0.35-8.0keV); error listed in adjacent
column. The photon flux is computed from the sum of the photon fluxes
in the 0.35-1.1, 1.1-2.6, and 2.6-8.0keV bands. The photon fluxes are
computed using the net counts in the band, the mean effective area in
the band, and the exposure. The mean effective area for each band is
computed assuming a flat spectrum.
Note (3): HR1=(M-S)/(S+M+H), HR2=(H-M)/(S+M+H) where S=0.35-1.1keV,
M=1.1-2.6keV and H=2.6-8keV
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- ChASeM33 ChASeM33 source ID number
5- 7 I3 --- [PMH2004] ? XMM Pietsch et al. (2004,
Cat. J/A+A/426/11) source ID number
9- 11 I3 --- [MPH2006] ? XMM Misanovic et al. (2006,
Cat. J/A+A/448/1247) source ID number
13- 28 A16 --- CXOU Chandra Grimm et al. (2005,
Cat. J/ApJS/161/271) source ID number
(JHHMMSS.s+DDMMSS)
30- 86 A57 --- OName/Comm SNRs Gordon et al. (1998ApJS..117...89G 1998ApJS..117...89G),
UIT sources Massey et al. (1996,
Cat. J/ApJ/469/629) (1)
88 A1 --- Note [efg] References for the comment (2)
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Note (1): M33SNR NN for SNR or [MBH96] NNN for UIT sources in Simbad
Note (2): References as follows:
e = Hatzidimitriou et al. (2006, Cat. J/A+A/451/835)
f = Pietsch et al. (2006ATel..905....1P 2006ATel..905....1P)
g = Williams et al. (2007, private communication)
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 05-Jun-2009