J/MNRAS/383/330 Chandra Small Magellanic Cloud Wing Survey (McGowan+, 2008)
The Chandra Small Magellanic Cloud Wing Survey - the search for X-ray binaries.
McGowan K.E., Coe M.J., Schurch M.P.E., McBride V.A., Galache J.L.,
Edge W.R.T., Corbet R.H.D., Laycock S., Buckley D.A.H.
<Mon. Not. R. Astron. Soc., 383, 330-338 (2008)>
=2008MNRAS.383..330M 2008MNRAS.383..330M
ADC_Keywords: Magellanic Clouds ; X-ray sources
Keywords: stars: emission-line, Be - Magellanic Clouds - X-rays: binaries
Abstract:
We have detected 523 sources in a survey of the Small Magellanic Cloud
(SMC) Wing with Chandra. By cross-correlating the X-ray data with
optical and near-infrared catalogues, we have found 300 matches. Using
a technique that combines X-ray colours and X-ray to optical flux
ratios, we have been able to assign preliminary classifications to 265
of the objects. Our identifications include four pulsars, one
high-mass X-ray binary (HMXB) candidate, 34 stars and 185 active
galactic nuclei (AGN). In addition, we have classified 32 sources as
hard AGN which are likely absorbed by local gas and dust, and nine
soft AGN whose nature is still unclear. Considering the abundance of
HMXBs discovered so far in the Bar of the SMC the number that we have
detected in the Wing is low.
Description:
Observations in the Wing of the SMC were made from 2005 July to 2006
March with Chandra. The survey consisted of 20 fields, with exposure
times ranging from 8.6-10.3ks.
X-ray parameters for 523 sources detected in the Wing of the Small
Magellanic Cloud with Chandra are presented. For each source
equatorial coordinates, positional error, net counts (total counts
minus background counts) in the 0.5-8.0keV band, signal-to-noise of
the detection and source flux in the 0.5-8.0keV band are given. The
median, compressed median and normalized quartile ratio of the photon
energy distribution, determined using quantile analysis, are given for
sources with three or more counts. For the sources that have optical
counterparts the V- and R-band magnitudes, B-V colour, X-ray to
optical flux ratios based on the V- and R-band magnitudes, and a
preliminary classification for the sources are given.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 106 523 The SMC Wing Survey catalogue
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See also:
J/A+AS/136/81 : A ROSAT PSPC X-Ray Survey of the SMC (Kahabka, 1999)
J/A+AS/142/41 : SMC X-ray sources ROSAT PSPC catalogue (Haberl+, 2000)
J/A+AS/147/75 : ROSAT HRI catalogue of SMC X-ray sources (Sasaki+, 2000)
J/PASJ/55/161 : ASCA sources in the SMC (Yokogawa+, 2003)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- [MCS2008] SMC Wing Survey catalogue number
5- 6 I2 h RAh X-ray Right Ascension J2000 (hours)
8- 9 I2 min RAm X-ray Right Ascension J2000 (minutes)
11- 15 F5.2 s RAs X-ray Right Ascension J2000 (seconds)
17 A1 --- DE- X-ray Declination J2000 (sign)
18- 19 I2 deg DEd X-ray Declination J2000 (degrees)
21- 22 I2 arcmin DEm X-ray Declination J2000 (minutes)
24- 27 F4.1 arcsec DEs X-ray Declination J2000 (seconds)
29- 33 F5.2 arcsec e_Pos Position mean error
35- 38 I4 ct Ncts Net counts
40- 44 F5.1 --- S/N Signal-to-noise
46- 51 F6.2 10-17W/m2 FX X-ray flux (0.5-8.0keV band,
in 10-10erg/cm2/s)
53- 56 F4.2 keV m ? Median of photon energy distribution
58- 62 F5.2 --- log(m/(1-m)) ? Compressed median
64- 67 F4.2 --- 3Q25/Q75 ? Normalised quartile ratio of photon energy
distribution
69- 72 F4.1 mag Vmag ? Magnitude (apparent) in V filter
74- 77 F4.1 mag Rmag ? Magnitude (apparent) in R filter
79- 84 F6.3 --- B-V ? B-V colour index
86- 93 E8.3 --- fXH/fV ? Ratio of hard (2-10keV) X-ray flux to
V filter flux (1)
95- 99 F5.2 [-] log(fXS/fR) ? Ratio of soft (0.5-2 keV) X-ray flux to
R filter flux (2)
101-106 A6 --- Class ? Classification of source (3)
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Note (1): where fV=8x10-6x10(-Vmag/2.5)
Note (2): where log(fXS/fR)=log(fXS)+5.50+Rmag/2.5
Note (3): where the source is classified as follows:
star = star
AGN = Active Galaxy Nucleus
AGN h = hard AGN
AGN s = soft AGN
pulsar = pulsar
HMXB? = High-Mass X-ray Binary candidate
* = sources with optical matches that were not able to be classified
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Acknowledgements:
Katherine McGowan, kem(at)astro.soton.ac.uk
(End) Patricia Vannier [CDS] 24-Apr-2008