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arXiv · 1903.03045

Evidence for recent GeV brightening of the SN 1987A region

Denys Malyshev·Gerd Pühlhofer·Andrea Santangelo·Jacco Vink
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Abstract

We report on a recent (2016-2018) enhancement of the GeV emission from the SN 1987A region as observed with Fermi/LAT. The observed signal is characterised by a power-law spectrum with a slope of 2.1 +/- 0.2 and is detected only at energies >1 GeV. The Fermi/LAT data constrain the position of the signal to within 0.15 degree around SN 1987A. Although a recent increase in the gamma-ray emission from SN 1987A seems to be a natural explanation for the detected emission, given the youth of the source and its rapid evolution, the Fermi/LAT location also overlaps with several other potential gamma-ray sources: 30 Dor C, Honeycomb nebula, RX J0536.9-6913, and a hypothetical, previously unknown transient source. We argue that multiwavelength observations of the region performed during the next few years can clarify the nature of the signal and encourage such observations. We also present upper limits on the time-averaged flux of SN 1987A based on 10 years of Fermi/LAT exposure, which can be used to better constrain the particle acceleration models of this source.

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Denys Malyshev, Gerd Pühlhofer, Andrea Santangelo, Jacco Vink. 2019-03-07. Evidence for recent GeV brightening of the SN 1987A region. https://arxiv.org/abs/1903.03045

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