X-Ray Variability in M87
Abstract
We present the evidence for X-ray variability from the core and from knot A in the M87 jet based on data from two observations with the Einstein Observatory High Resolution Imager (HRI) and three observations with the ROSAT HRI. The core intensity showed a 16% increase in 17 months ('79-'80); a 12% increase in the 3 years '92 to '95; and a 17% drop in the last half of 1995. The intensity of knot A appears to have decreased by 16% between 92Jun and 95Dec. Although the core variability is consistent with general expectations for AGB nuclei, the changes in knot A provide constraints on the x-ray emission process and geometry. Thus we predict that the x-ray morphology of knot A will differ significantly from the radio and optical structure.
- Publication:
-
NASA STI/Recon Technical Report N
- Pub Date:
- June 2000
- Bibcode:
- 2000STIN...0064087H
- Keywords:
-
- X Rays;
- Variability;
- Active Galactic Nuclei;
- Elliptical Galaxies;
- Luminous Intensity;
- Heao 2;
- High Resolution;
- Rosat Mission;
- X Ray Astronomy;
- Space Radiation