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An Unidentified Variable Gamma-Ray Source near the Galactic Plane Detected by COMPTEL

S. Zhang·W. Collmar·V. Schonfelder
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Abstract

We report the detection of an unidentified gamma-ray source near the Galactic plane by the COMPTEL experiment aboard the Compton Gamma-Ray Observatory. The source is detected at a significance level of ~ 7.2 sigma in the energy range 1-3 MeV and at ~ 4.6 sigma in the lower 0.75-1 MeV band in the time period March to July 1995. At energies above 3 MeV are only marginal hints or upper limits obtained. The MeV spectrum has a soft shape. Strong flux variability is found within one year at energies below 3 MeV. Possible counterparts of galactic and extragalactic nature are discussed.

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S. Zhang, W. Collmar, V. Schonfelder. 2002-10-10. An Unidentified Variable Gamma-Ray Source near the Galactic Plane Detected by COMPTEL. https://doi.org/10.1051/0004-6361%3A20021434

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