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arXiv · astro-ph/9612055

X-ray variability in M87

D. E. Harris·J. A. Biretta·W. Junor
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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 AGN 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.

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D. E. Harris, J. A. Biretta, W. Junor. 1996-12-05. X-ray variability in M87. https://doi.org/10.1093/mnras%2F284.4.l21

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