Soft diffuse X-rays in the southern galactic hemisphere.
Abstract
A map is presented of the soft X-ray diffuse background flux in the C band (approximately 0.13-0.28 keV) covering almost all of the southern galactic hemisphere. A comparison at constant galactic latitude of both C band and B band (about 0.1-0.18 keV) soft X-ray data with neutral-hydrogen maps shows that the intensity does decrease with increasing neutral-hydrogen column density but in a manner that is inconsistent with photoelectric absorption. It is suggested that the inverse correlation is a displacement effect. X-ray emission regions appear to be where the cool gas is not. Further, the evidence against photoelectric absorption implies that the bulk of the cool gas is beyond the X-ray emitting regions. Fewer than 10 to the 20th power H atoms per sq cm can be between the sun and the X-ray emitting regions. The sun appears to be surrounded by a soft X-ray emission region consisting of gas at a temperature of about 1 million K.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- October 1977
- DOI:
- 10.1086/182545
- Bibcode:
- 1977ApJ...217L..87S
- Keywords:
-
- Background Radiation;
- Cosmic Gases;
- Extraterrestrial Radiation;
- Hydrogen Atoms;
- Interstellar Matter;
- X Ray Astronomy;
- C Band;
- Diffuse Radiation;
- Galactic Structure;
- Gas Density;
- Intergalactic Media;
- Southern Hemisphere;
- Space Radiation