https://doi.org/10.1051/epjconf/201612503010
Fermi bubbles around the M31 galaxy
1 Sternberg Astronomical Institute, Lomonosov Moscow State University, Universitetsky prospekt 13, 119992, Moscow, Russia
2 Institute for Nuclear Research of the Russian Academy of Sciences, 117312, Moscow, Russia
3 Pushchino Radio Astronomy Observatory, 142290 Pushchino, Russia
4 IMPRS Max Planck Institute for Astronomy, D-69117, Heidelberg, Germany
* e-mail: pshirkov@sai.msu.ru
** e-mail: vasilyev@mpia.de
*** e-mail: kp@sai.msu.ru
Published online: 28 October 2016
We have searched for an extended high-energy gamma-ray emission around the nearby giant spiral Andromeda galaxy M31 using almost 7 years of Fermi LAT data at energies above 300 MeV. The presence of a diffuse gamma-ray halo with total photon flux 2:6±0:6×10−9 cm−2 s−1, corresponding to a luminosity (0.3-100 GeV) of (3:2±0:6)×1038 erg s−1 (for a distance of 780 kpc) was found at a 5.3σ confidence level. The best-fit halo template corresponds to two 6-7.5 kpc bubbles symmetrically located perpendicular to the M31 galactic disc, similar to the ‘Fermi bubbles’ found around the Milky Way centre.
© The Authors, published by EDP Sciences, 2016
This is an Open Access article distributed under the terms of the Creative Commons Attribution License 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
