Discovery of Evidence for Correlated X-ray/GeV Variability in the Feb. 2010 Flare of Mrk 421
Abstract
We report on observations of the high-synchrotron-peaked BL Lac (HBL) Markarian 421 during a bright X-ray flaring period in February 2010. Combining data in the GeV band, obtained by the Fermi Large Area Telescope, with data in the X-rays, obtained by the RXTE, Swift, and MAXI observatories, we find evidence for correlated variability between the X-ray and GeV emission for the first time in an HBL. Including data from the UVOT instrument aboard Swift, we model the spectral energy distribution of the source in the pre-flare, flare and post-flare time periods using the standard synchrotron self-Compton model. In the context of these models, the GeV and X-ray emission arise from electrons with significantly different energies in the particle distributions that are inferred from the models. We discuss the constraints that the correlated X-ray/GeV temporal behavior places on the properties of the emitting plasma during this flare.
- Publication:
-
American Astronomical Society Meeting Abstracts #219
- Pub Date:
- January 2012
- Bibcode:
- 2012AAS...21914907M