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A search for gamma-ray emission from the Galactic plane in the longitude range between 37 deg and 43 deg

HEGRA-Collaboration·F. Aharonian
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Abstract

Using the HEGRA system of imaging atmospheric Cherenkov telescopes, a region of the Galactic plane (-10 deg < b < 5 deg, 38 deg < l < 43 deg) was surveyed for TeV gamma-ray emission, both from point sources and of diffuse nature. The region covered includes 15 known pulsars, 6 known supernova remnants (SNR) and one unidentified EGRET source. No evidence for emission from point sources was detected; upper limits are typically below 0.1 Crab units for the flux above 1 TeV. For the diffuse gamma-ray flux from the Galactic plane, an upper limit of 6.1*10E-15 ph/(cm2 s sr MeV) was derived under the assumption that the spatial distribution measured by the EGRET instrument extends to the TeV regime. This upper flux limit is a factor of about 1.5 larger than the flux expected from the ensemble of gamma-ray unresolved Galactic cosmic ray sources.

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HEGRA-Collaboration, F. Aharonian. 2001-06-28. A search for gamma-ray emission from the Galactic plane in the longitude range between 37 deg and 43 deg. https://arxiv.org/abs/astro-ph/0106528

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