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Rapid Variability of Gamma-Ray Blazars: A Model for MKN 421

M. Salvati·M. Spada·F. Pacini
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Abstract

The extremely rapid burst of TeV photons from Mkn 421 (15 May 1996) can be reconciled with the standard properties of a relativistic gamma-ray emitting jet (bulk Lorentz factor $\approx$ 10; size $\10^{17}$ cm) if one assumes that the electrons are accelerated in conical shocks with both opening and viewing angles $\approx 1/Γ$. If the injection time and the cooling time are much less than the photon crossing time, an emission ring moves along the jet and leads to the appearance of a very rapid flare, in satisfactory agreement with the observations.

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M. Salvati, M. Spada, F. Pacini. 1998-01-07. Rapid Variability of Gamma-Ray Blazars: A Model for MKN 421. https://doi.org/10.1086/311216

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