Absorption and production of soft x-rays in the Galaxy

Conference · Mon Jan 01 04:00:00 EST 1973 · Int. Astron. Union Symp., no. 55, pp. 235-249

OSTI ID:4426229

Hayakawa, S

From symposium X - and gamma -ray astronomy; Madrid, Spain (11 May 1972). See CONF-720599-. The column densities of interstellar hydrogen to x- ray sources derived from their spectra are compared with those obtained from 21 cm radio observations. Referring to several observed results on Cyg X-2, Cygnus Loop, etc., the interpretation of the low energy cut-off of the spectrum in terms of the interstellar absorption is subject to ambiguities due to a modification of the emission spectrum by Compton scattering in the sources and the contribution of emission lines. The result of soft x-ray sky surveys indicates that the diffuse component of soft x rays consists of the extragalactic and the galactic components. The former has a hard component with a power law spectrum and a soft component which may be represented by an exponential spectrum. The galactic component is so soft that its spectrum may also be explained by thermal bremsstrahlung of temperature of about 0.1 keV. Its generation rate may account for the heating and ionization of interstellar matter. It is suggested that galactic diffuse soft x rays are produced by active stars of a rather high number density. (auth)

• Research Organization: Nagoya Univ., Japan
• NSA Number: NSA-29-008546
• OSTI ID: 4426229
• Conference Information: Journal Name: Int. Astron. Union Symp., no. 55, pp. 235-249
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

*HYDROGEN-- INTERSTELLAR SPACE
*MILKY WAY-- SOFT X RADIATION
*STARS- - SOFT X RADIATION
ABSORPTION
BACKGROUND RADIATION
ENERGY SPECTRA
INTERGALACTIC SPACE
N56300 --Physics (Astrophysics & Cosmology)--Quasi-stellar
Radio & X-Ray Sources
N56500* --Physics (Astrophysics & Cosmology)--Galaxies