J/ApJ/599/218 Chandra LMXB in NGC 4365 and NGC 4382 (Sivakoff+, 2003)
Chandra observations of low-mass X-ray binaries and diffuse gas in the
early-type galaxies NGC 4365 and NGC 4382 (M85).
Sivakoff G.R., Sarazin C.L., Irwin J.A.
<Astrophys. J., 599, 218-236 (2003)>
=2003ApJ...599..218S 2003ApJ...599..218S
ADC_Keywords: Binaries, X-ray
Keywords: binaries: close - galaxies: elliptical and lenticular, cD -
galaxies: ISM - X-rays: binaries - X-rays: galaxies - X-rays: ISM
Abstract:
We used the Chandra X-Ray Observatory ACIS-S3 to image the X-ray-faint
elliptical galaxy NGC 4365 and lenticular galaxy NGC 4382. The
observations resolve much of the X-ray emission into 99 and 58
sources, respectively, most of which are low-mass X-ray binaries
(LMXBs) associated with each of the galaxies. Within one effective
radius of NGC 4365, about 45% of the counts are resolved into sources,
30% are attributed to unresolved LMXBs, and 25% are attributed to
diffuse gas. Within two effective radii of NGC 4382, about 22% of the
counts are resolved into sources, 33% are attributed to unresolved
LMXBs, and 45% are attributed to diffuse gas. We identify 18 out of
the 37 X-ray sources in a central field in NGC 4365 with globular
clusters.
Description:
NGC 4365 was observed on 2001 June 23 with a live exposure of 40429s,
while NGC 4382 was observed on 2001 May 29-30 for 39749s.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 118 99 Discrete X-Ray Sources in NGC 4365
table2.dat 116 58 Discrete X-Ray Sources in NGC 4382 (M85)
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See also:
V/113 : Cataclysmic Binaries, LMXBs, & related objects (Ritter+, 2003)
J/ApJ/600/729 : Chandra LMXB in NGC 4649 (Randall+, 2004)
Byte-by-byte Description of file: table1.dat table2.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- [SSI2003b] Sequential number (1)
4- 7 A4 --- --- [CXOU]
9- 24 A16 --- CXOU CXOU designation (JHHMMSS.s+DDMMSS)
26- 27 I2 h RAh Right ascension (J2000)
29- 30 I2 min RAm Right ascension (J2000)
32- 36 F5.2 s RAs Right ascension (J2000)
38 A1 --- DE- Declination sign (J2000)
39- 40 I2 deg DEd Declination (J2000)
42- 43 I2 arcmin DEm Declination (J2000)
45- 48 F4.1 arcsec DEs Declination (J2000)
50- 54 F5.1 arcsec Dist Distance from the center of the galaxy
56- 61 F6.2 10-4s-1 CRate X-ray Count rate
63- 66 F4.2 10-4s-1 e_CRate rms uncertainty on CRate
68- 72 F5.2 --- S/N signal-to-noise ratio
74- 79 F6.2 10+30W LX X-ray luminosity in the 0.3-10keV band
81- 85 F5.2 --- H21 Hardness ratio, (M-S)/(M+S) (2)
87- 90 F4.2 --- E_H21 Error on H21 (Upper limit)
92- 95 F4.2 --- e_H21 Error on H21 (Lower limit)
97-101 F5.2 --- H31 Hardness ratio, (H-S)/(H+S) (2)
103-106 F4.2 --- E_H31 Error on H31 (Upper limit)
108-111 F4.2 --- e_H31 Error on H31 (Lower limit)
113-115 A3 --- Notes Individual notes (3)
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Note (1): [SSI2003b] NGC 4365 NN in table1, [SSI2003b] NGC 4382 NN in table2.
Note (2): S, M, and H are the total counts in the soft (0.3-1keV),
medium (1-2keV), and hard (2-10keV) bands, respectively.
Note (3): Notes are the following:
a: Sources near the center may be confused with nearby sources,
making their positions, fluxes, and extents uncertain.
b: Source is noticeably more extended than PSF.
c: Possible faint optical counterpart.
d: Globular cluster is possible optical counterpart.
e: Source may be variable.
f: Source is at the edge of the S3 detector, and flux is uncertain
as a result of large exposure correction.
g: Identified with known AGN.
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History:
From electronic version of the journal
(End) James Marcout, Patricia Bauer [CDS] 05-Feb-2004