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Warm absorbers in the rosat spectra of quasars
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Fiore, Fabrizio |
| Copyright Year | 1998 |
| Description | We present two ROSAT PSPC observations of the radio-loud, lobe-dominated quasar 3C 351, which shows an 'ionized absorber' in its X-ray spectrum. The factor 1.7 change in flux in the approx. 2 years between the observations allows a test of of models for this ionized absorber. The absorption feature at approx. 0.7 keV (quasar frame) is present in both spectra but with a lower optical depth when the source intensity - and hence the ionizing flux at the absorber - is higher, in accordance with a simple, single-zone, equilibrium photoionization model. Detailed modeling confirms this agreement quantitatively. The maximum response time of 2 years allows us to limit the gas density: n(sub e) greater than 2 x 10(exp 4)cm(exp -3); and the distance of the ionized gas from the central source R less than 19 pc. This produces a strong test for a photoionized absorber in 3C 351: a factor 2 flux change in approx. 1 week in this source must show non-equilibrium effects in the ionized absorber. |
| File Size | 2216308 |
| Page Count | 50 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_19990013985 |
| Archival Resource Key | ark:/13960/t72v7gm0g |
| Language | English |
| Publisher Date | 1998-12-01 |
| Access Restriction | Open |
| Subject Keyword | Astrophysics Rosat Mission Quasars Ionized Gases Spectra X Ray Optics Cosmic Rays Gas Density Gamma Rays X Rays Photoionization X Ray Binaries Emission Spectra Far Ultraviolet Radiation Optical Thickness X Ray Sources Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Technical Report |
