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Precursor active galaxies and the cosmic x-ray background
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Boldt, E. A. Leiter, D. |
| Copyright Year | 1981 |
| Description | It is argued that the cosmic X-ray background (CXB) is not dominated by sources that are usual active galaxies or quasars. A comparable number of objects, young galaxies at z approximately 4 containing massive black holes surrounded by hot optically thin accretion disks, constitute the precursor active galaxies (PAG) postulated here for producing the thermal type spectrum required for the CXB. An evolutionary track for such PAG objects is described which would lead to the active galaxies observed as individual nonthermal sources. Unresolved emission from active galaxies at z 1 could then readily account for most of the nonthermal background observed in the gamma ray band. |
| File Size | 651962 |
| Page Count | 17 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_19810011472 |
| Archival Resource Key | ark:/13960/t0fv3cx1q |
| Language | English |
| Publisher Date | 1981-02-01 |
| Access Restriction | Open |
| Subject Keyword | Space Radiation Active Galaxies Gamma Rays Galaxies Galactic Evolution X Ray Astronomy Cosmic X Rays Background Radiation Nonthermal Radiation Black Holes Astronomy Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Article |
