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Observation of Strong Variability in the X-Ray Emission from Markarian 421 Correlated with the May 1996 TeV Flare

Michael Schubnell
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Abstract

We observed the BL Lac object Markarian 421 with the X-ray satellite RXTE and the Whipple Air Cerenkov Telescope during a two week correlated X-ray/gamma-ray campaign in May 1996. Two dramatic outbursts with extremely rapid and strong flux variations were observed at TeV energies during this period. The X-ray emission in the 2-10 keV band was highly variable and reached a peak flux of $5.6\times10^{-10}$ erg cm$^{-2}$ s$^{-1}$, a historic high. Similar behavior was observed for the TeV emission. In contrast to earlier near-simultaneous X-ray/gamma-ray observations of Mrk 421, the variability amplitude is much larger at TeV than at X-ray energies. This behavior is expected in Synchrotron Self-Compton models.

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Michael Schubnell. 1997-07-11. Observation of Strong Variability in the X-Ray Emission from Markarian 421 Correlated with the May 1996 TeV Flare. https://doi.org/10.1063/1.54062

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