J/ApJ/601/735 M51 luminous X-ray sources (Terashima+, 2004)
The luminous X-ray source population in M51 observed with Chandra.
Terashima Y., Wilson A.S.
<Astrophys. J., 601, 735-758 (2004)>
=2004ApJ...601..735T 2004ApJ...601..735T
ADC_Keywords: X-ray sources
Keywords: accretion, accretion disks - galaxies: active -
galaxies: individual (M51) - X-rays: binaries - X-rays: galaxies
Abstract:
We present the results of two Chandra observations (separated by 1yr)
of the population of X-ray sources in the spiral galaxy M51 (NGC 5194
and NGC 5195). One hundred and thirteen X-ray sources have been
detected in an 8.4'x8.4'(20.4x20.4kpc) region, and 84 and 12 of them
project within the disks of NGC 5194 and NGC 5195, respectively. Nine
and 28 sources have luminosities exceeding 1x1039erg/s
(ultraluminous X-ray sources or ULXs) and 1x1038erg/s in the
0.5-8keV band, respectively, assuming that they are associated with
M51. The number of ULXs is much higher than found in most normal
spiral and elliptical galaxies. Most of the X-ray sources and all
seven of the ULXs in NGC 5194 are located in, or close to, a spiral
arm, suggesting a connection with recent star formation.
Description:
Chandra observations of M51 were performed on 2000 June 20 and 2001
June 23 with the ACIS instrument. The background was stable in both
observations, and effective exposure times of 14.9 and 26.8ks were
obtained for the observations in 2000 and 2001, respectively.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 153 84 Sources spatially coincident with NGC 5194
table3.dat 153 12 Sources spatially coincident with NGC 5195
table4.dat 153 17 Other sources
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See also:
B/chandra : The Chandra Archive Log (CXC, 2002)
Byte-by-byte Description of file: table2.dat table3.dat table4.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- [TW2004] Sequential number (1)
4- 5 I2 h RAh Right ascension (J2000.0)
7- 8 I2 min RAm Right ascension (J2000.0)
10- 14 F5.2 s RAs Right ascension (J2000.0)
16 A1 ---- DE- Declination sign (J2000.0)
17- 18 I2 deg DEd Declination (J2000.0)
20- 21 I2 arcmin DEm Declination (J2000.0)
23- 26 F4.1 arcsec DEs Declination (J2000.0)
28- 43 A16 --- CXOM51 Chandra designation
45- 50 F6.1 ct 0.5-8keV 0.5-8keV band counts in observations 1 & 2
52- 55 F4.1 ct e_0.5-8keV rms uncertainty on 0.5-8keV
57 A1 --- l_0.5-2keV Limit flag on 0.5-2keV
58- 63 F6.1 ct 0.5-2keV 0.5-2keV band counts in observations 1 & 2
65- 68 F4.1 ct e_0.5-2keV ? rms uncertainty on 0.5-2keV
70 A1 --- l_2-8keV Limit flag on 2-8keV
71- 76 F6.1 ct 2-8keV 2-8keV band counts in observations 1 & 2
78- 81 F4.1 ct e_2-8keV ? rms uncertainty on 2-8keV
83 A1 --- l_0.5-8keV1 Limit flag on 0.5-8keV1
84- 88 F5.1 ct 0.5-8keV1 0.5-8keV band counts in observation 1
90- 93 F4.1 ct e_0.5-8keV1 ? rms uncertainty on 0.5-8keV1
95 A1 --- l_0.5-2keV1 Limit flag on 0.5-2keV1
96-100 F5.1 ct 0.5-2keV1 0.5-2keV band counts in observation 1
102-105 F4.1 ct e_0.5-2keV1 ? rms uncertainty on 0.5-2keV1
107 A1 --- l_2-8keV1 Limit flag on 2-8keV1
108-112 F5.1 ct 2-8keV1 2-8keV band counts in observation 1
114-117 F4.1 ct e_2-8keV1 ? rms uncertainty on 2-8keV1
119 A1 --- l_0.5-8keV2 Limit flag on 0.5-8keV2
120-124 F5.1 ct 0.5-8keV2 0.5-8keV band counts in observation 2
126-129 F4.1 ct e_0.5-8keV2 ? rms uncertainty on 0.5-8keV2
131 A1 --- l_0.5-2keV2 Limit flag on 0.5-2keV2
132-136 F5.1 ct 0.5-2keV2 0.5-2keV band counts in observation 2
138-141 F4.1 ct e_0.5-2keV2 ? rms uncertainty on 0.5-2keV2
143 A1 --- l_2-8keV2 Limit flag on 2-8keV2
144-148 F5.1 ct 2-8keV2 2-8keV band counts in observation 2
150-153 F4.1 ct e_2-8keV2 ? rms uncertainty on 2-8keV2
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Note (1): Source designations in Simbad:
[TW2004] NGC 5194 NN in table2
[TW2004] NGC 5195 NN in table3
[TW2004] Source NN in table4
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History:
From electronic version of the journal
(End) James Marcout, Patricia Vannier [CDS] 06-Apr-2004