| Autor: |
Jill Bechtold, Craig B. Foltz, Paul S. Smith, Gary D. Schmidt, T. Aldcroft |
| Rok vydání: |
1997 |
| Předmět: |
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| Zdroj: |
International Astronomical Union Colloquium. 163:681-682 |
| ISSN: |
0252-9211 |
| DOI: |
10.1017/s0252921100043396 |
| Popis: |
The physical origin of associated absorption lines (zabs ≈ zqso) which are observed in radio-loud quasar is generally not well understood. Two observable properties, line variability and quasar optical polarization, can serve to constrain the possibilities. To this end, we have obtained high-resolution spectra (1 Å) and broad-band optical polarizations for over 30 radio-loud quasars with known CIV associated absorption. The quasars are at redshifts between about 1 and 2, and were previously observed spectroscopically at similar resolution between 1985 – 1986 by Foltz et al (1987). The associated CIV absorption systems include a variety of velocity profiles from weak single lines to very complex multi-component systems to the BAL-like profile of PHL 1157+0128. In this poster we show the first strong evidence for line variability in z > 1 radio-loud quasars. We find that in general the variability is less than ~ 30%. The optical polarization of CIV absorbed quasars is consistent with all radio-loud quasars. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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