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

S. D. Bloom
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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.

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S. D. Bloom. 1997-09-25. Observations of a Correlated Gamma-Ray and Optical Flare for BL Lacertae. https://doi.org/10.1086/311035

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