SAS 3 survey of the soft X-ray background

Abstract

view Abstract Citations (122) References (42) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS SAS 3 survey of the soft X-ray background. Marshall, F. J. ; Clark, G. W. Abstract The results of a survey of the soft X-ray sky in the C band (0.10-0.28keV) are reported. The observations were carried out using two independent flow proportional counters on board the SAS 3 X-ray satellite which had a total angular resolution of 2.9 deg FWHM, and a total exposure of 2.2 x 10 to the 4th per sq cm s sr. It is found that C band counting rates were generally inversely correlated with the column density of the neutral hydrogen on all angular scales down to the lowest angular resolution of the detectors. In the region 90-180 deg l and 0-10 deg b, the relation between C-band rates and the column densities of neutral hydrogen was fitted with a residual rms deviation of less than 13 percent by a two-component numerical model of the X-ray background. For the apparent attenuation column density a value of 2.7 x 10 to the 20th per sq cm was obtained. On the basis of a computer simulation of the SAS 3 data, it is shown that the observed clumping of interstellar matter was consistent with the magnitude of spatial fluctuations in the C-band map. When the background rates were subtracted from the survey map, the subsequent map showed foreground emission and absorption features with improved sensitivity and clarity. A series of computer-generated maps incorporating the SAS 3 data is given in an appendix. Publication: The Astrophysical Journal Pub Date: December 1984 DOI: 10.1086/162721 Bibcode: 1984ApJ...287..633M Keywords: Interstellar Gas; Milky Way Galaxy; Sas-3; X Ray Sources; Computerized Simulation; Data Processing; Hydrogen; Monte Carlo Method; Neutral Gases; Astrophysics full text sources ADS | data products SIMBAD (14) NED (2)