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J/ApJ/598/969       Chandra X-ray sources in NGC 3556        (Wang+, 2003)

Chandra observation of the edge-on galaxy NGC 3556 (M108): violent galactic disk-halo interaction revealed. Wang Q.D., Chaves T., Irwin J.A. <Astrophys. J., 598, 969-981 (2003)> =2003ApJ...598..969W
ADC_Keywords: X-ray sources Keywords: galaxies: general - galaxies: individual (NGC 3556) - galaxies: spiral - X-rays: general Abstract: We present a 60ks Chandra ACIS-S observation of the isolated edge-on spiral galaxy NGC 3556, together with a multiwavelength analysis of various discrete X-ray sources and diffuse X-ray features. Description: Our Chandra observation of NGC 3556 (observation ID 2025) was taken between 2001 September 8 and 9 for an exposure of 60ks. The instrument ACIS-S was at the focal plane of the telescope. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table2.dat 86 83 Chandra Source List
See also: B/chandra : The Chandra Archive Log (CXC, 2002) Byte-by-byte Description of file: table2.dat
Bytes Format Units Label Explanations
1- 2 I2 --- [WCI2003] Sequential number of the source 4- 22 A19 --- CXOU CXOU Name (JHHMMSS.SS+DDMMSS.s, J2000) 24- 26 F3.1 arcsec ePos Position uncertainty 28- 32 F5.1 --- logP False detection probability (1) 34- 38 F5.2 ct/ks CR On-axis (exposure-corrected) source count rate in the 0.3-7keV band. 40- 43 F4.2 ct/ks e_CR rms uncertainty on CR 45- 49 F5.2 --- HR ? Hardness ratio, HR=(H-S)/(H+S) (2) 51- 54 F4.2 --- e_HR ? rms uncertainty on HR 56- 60 F5.2 --- HR1 ? Hardness ratio 1, HR1=(S2-S1)/S (2) 62- 65 F4.2 --- e_HR1 ? rms uncertainty on HR1 67- 71 F5.2 --- HR2 ? Hardness ratio 2, HR2=(H2-H1)/H (2) 73- 76 F4.2 --- e_HR2 ? rms uncertainty on HR2 78 A1 --- Band [BSH] Band in which a source is detected with the most accurate position (2)
Note (1): The false detection probability P that the detected number of counts may result from the Poisson fluctuation of the local background within the detection aperture (logP←20.0 is set to -20.0). Note (2): Hardness ratios are defined by: S1 = net source count rates in the 0.3-0.7keV band S2 = net source count rates in the 0.7-1.5keV band H1 = net source count rates in the 1.5-3keV band H2 = net source count rates in the 3-7keV band S = S1+S2, H = H1+H2, B = S+H The hardness ratios are calculated only for sources with individual S/Ns greater than 4 in the broad band (B=S+H), and only the values with uncertainties less than 0.2 are included
History: From electronic version of the journal
(End) James Marcout, Patricia Vannier [CDS] 23-Jan-2004
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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