Evidence for 200 second variability in the X-ray flux of the quasar 1525 + 227
Abstract
Sixteen hundred seconds of Einstein Observatory IPC data for 1525 + 227, a bright, nearby quasar show significant intensity fluctuations on a time scale of 200 seconds. Similar fluctuations were not detected 13 months later during a follow-up 12,500 second observation. Interpretation of the time variations requires a Hubble constant equal to or greater than 100 km/s per Mpc to obtain even marginal consistency with standard isotropic emission models. An alternative interpretation invokes anisotropic emission probably due to the presence of relativistic motions with associated beaming effects.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- July 1982
- DOI:
- 10.1086/183819
- Bibcode:
- 1982ApJ...258L...1M
- Keywords:
-
- Flux (Rate);
- Quasars;
- Relativistic Particles;
- Variability;
- X Ray Sources;
- Anisotropy;
- Heao 2;
- Hubble Constant;
- Proportional Counters;
- Spaceborne Astronomy;
- Statistical Analysis;
- Astronomy