On the Gamma-Ray Emission of the Andromeda Galaxy M31
Using the γ -ray data obtained with the Large Area Telescope on board the Fermi Gamma-ray Space Telescope (Fermi) for ∼14 yr, we examine the high-energy emission emanating from the center of the Andromeda galaxy M31. Different from previously reported results, which show a seemingly extended source,...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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IOP Publishing
2023-01-01
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| Series: | The Astrophysical Journal Letters |
| Subjects: | |
| Online Access: | https://doi.org/10.3847/2041-8213/acbf4f |
| _version_ | 1797697183895519232 |
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| author | Yi Xing Zhongxiang Wang Dong Zheng Jie Li |
| author_facet | Yi Xing Zhongxiang Wang Dong Zheng Jie Li |
| author_sort | Yi Xing |
| collection | DOAJ |
| description | Using the γ -ray data obtained with the Large Area Telescope on board the Fermi Gamma-ray Space Telescope (Fermi) for ∼14 yr, we examine the high-energy emission emanating from the center of the Andromeda galaxy M31. Different from previously reported results, which show a seemingly extended source, we instead find two individual point sources, one consistent with being at the center and one 0.°4 southeast of the center. The emission of the former is well described using a log-parabola model, similar to those of previous studies, and that of the latter can be fitted with a power law. We discuss the possible origins for the two sources. M31's central source, now consistent with being a point source, necessitates a revisit of its previously discussed originations with this new property taken into consideration, in particular those cosmic rays or dark matter scenarios involving extended source distributions. The SE source appears to have a projected distance of ∼6 kpc from M31's center, and the investigation is required as to whether it is a source locally associated with M31, or is instead a background extragalactic one. |
| first_indexed | 2024-03-12T03:36:37Z |
| format | Article |
| id | doaj.art-5056a44a259f4371aeaecaa42c53739e |
| institution | Directory Open Access Journal |
| issn | 2041-8205 |
| language | English |
| last_indexed | 2024-03-12T03:36:37Z |
| publishDate | 2023-01-01 |
| publisher | IOP Publishing |
| record_format | Article |
| series | The Astrophysical Journal Letters |
| spelling | doaj.art-5056a44a259f4371aeaecaa42c53739e2023-09-03T13:08:54ZengIOP PublishingThe Astrophysical Journal Letters2041-82052023-01-019452L2210.3847/2041-8213/acbf4fOn the Gamma-Ray Emission of the Andromeda Galaxy M31Yi Xing0https://orcid.org/0000-0002-5818-0732Zhongxiang Wang1https://orcid.org/0000-0003-1984-3852Dong Zheng2Jie Li3https://orcid.org/0000-0003-2426-3852Key Laboratory for Research in Galaxies and Cosmology , Shanghai Astronomical Observatory, Chinese Academy of Sciences, 80 Nandan Road, Shanghai 200030, People's Republic of China ; yixing@shao.ac.cn, wangzx20@ynu.edu.cnKey Laboratory for Research in Galaxies and Cosmology , Shanghai Astronomical Observatory, Chinese Academy of Sciences, 80 Nandan Road, Shanghai 200030, People's Republic of China ; yixing@shao.ac.cn, wangzx20@ynu.edu.cn; Department of Astronomy, School of Physics and Astronomy, Yunnan University , Kunming 650091, People's Republic of ChinaDepartment of Astronomy, School of Physics and Astronomy, Yunnan University , Kunming 650091, People's Republic of ChinaLaboratory for Research in Galaxies and Cosmology, Department of Astronomy, University of Science and Technology of China , Hefei 230036, People's Republic of China; School of Astronomy and Space Science, University of Science and Technology of China , Hefei 230026, People's Republic of ChinaUsing the γ -ray data obtained with the Large Area Telescope on board the Fermi Gamma-ray Space Telescope (Fermi) for ∼14 yr, we examine the high-energy emission emanating from the center of the Andromeda galaxy M31. Different from previously reported results, which show a seemingly extended source, we instead find two individual point sources, one consistent with being at the center and one 0.°4 southeast of the center. The emission of the former is well described using a log-parabola model, similar to those of previous studies, and that of the latter can be fitted with a power law. We discuss the possible origins for the two sources. M31's central source, now consistent with being a point source, necessitates a revisit of its previously discussed originations with this new property taken into consideration, in particular those cosmic rays or dark matter scenarios involving extended source distributions. The SE source appears to have a projected distance of ∼6 kpc from M31's center, and the investigation is required as to whether it is a source locally associated with M31, or is instead a background extragalactic one.https://doi.org/10.3847/2041-8213/acbf4fGamma-ray sourcesAndromeda Galaxy |
| spellingShingle | Yi Xing Zhongxiang Wang Dong Zheng Jie Li On the Gamma-Ray Emission of the Andromeda Galaxy M31 The Astrophysical Journal Letters Gamma-ray sources Andromeda Galaxy |
| title | On the Gamma-Ray Emission of the Andromeda Galaxy M31 |
| title_full | On the Gamma-Ray Emission of the Andromeda Galaxy M31 |
| title_fullStr | On the Gamma-Ray Emission of the Andromeda Galaxy M31 |
| title_full_unstemmed | On the Gamma-Ray Emission of the Andromeda Galaxy M31 |
| title_short | On the Gamma-Ray Emission of the Andromeda Galaxy M31 |
| title_sort | on the gamma ray emission of the andromeda galaxy m31 |
| topic | Gamma-ray sources Andromeda Galaxy |
| url | https://doi.org/10.3847/2041-8213/acbf4f |
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