Observations of a Correlated Gamma-Ray and Optical Flare for BL Lacertae

Abstract

The latest observations of BL Lacertae with the EGRET instrument on CGRO show that the gamma-ray flux was four times higher than the previous detection. Within the 1997 July 15-22 observation there was a dramatic factor of 2.5 increase in the gamma-ray flux, with a sharp peak of about 8 hours, and apparently preceding a brief optical flare by several hours. The gamma-ray photon spectral index was significantly harder than that for the previous detection.

11 pages, 3 figures. To be published in the Astrophysical Journal Letters

References in corpus (1)

• Gamma-ray Flares and VLBI Outbursts of Blazars

Cited by in corpus (43)

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