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arXiv · 1709.00131

Search for the Gamma-ray Emission from M33 with Fermi LAT

Fu Lei·Xia Zi-qing·Shen Zhao-qiang
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Abstract

In the work we search for the $\gamma$-ray signal from M33, one of the biggest galaxies in the Local Group, by using the Pass 8 data of Fermi Large Area Telescope (LAT). No statistically significant gamma-ray emission has been detected in the direction of M33 and we report a new upper limit of high energy ($>100\,\rm MeV$) photon flux of $2.3\times 10^{-9}\,\rm ph\,cm^{-2}\,s^{-1}$, which is more strict than previous constrains and implies a cosmic ray density of M33 lower than that speculated previously. Nevertheless the current limit is still in agreement with the correlation of star formation rate and $\gamma$-ray luminosity inferred from the Local group galaxies and a few nearby starburst galaxies.

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Fu Lei, Xia Zi-qing, Shen Zhao-qiang. 2017-09-01. Search for the Gamma-ray Emission from M33 with Fermi LAT. https://doi.org/10.1093/mnras%2Fstx929

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