Possible association of two Stellar Bowshocks with Unidentified Fermi Sources
- The bowshocks of runaway stars had been theoretically proposed as gamma-ray sources. However, this hypothesis has not been confirmed by observations to date. In this paper, we present two runaway stars (lambda Cep and LS 2355) whose bowshocks are coincident with the unidentified Fermi gamma-ray sources 3FLG J2210.1+5925 and 3FGL J1128.7-6232, respectively. After performing a cross-correlation between different catalogs at distinct wavelengths, we found that these bowshocks are the most peculiar objects in the Fermi position ellipses. Then we computed the inverse Compton emission and fitted the Fermi data in order to test the viability of both runaway stars as potential counterparts of the two high-energy sources. We obtained very reasonable values for the fitted parameters of both stars. We also evaluated the possibility for the source 3FGL J1128.7-6232, which is positionally coincident with a H II region, to be the result of background cosmic-ray protons interacting with the matter of the cloud, as well as the probability of a pureThe bowshocks of runaway stars had been theoretically proposed as gamma-ray sources. However, this hypothesis has not been confirmed by observations to date. In this paper, we present two runaway stars (lambda Cep and LS 2355) whose bowshocks are coincident with the unidentified Fermi gamma-ray sources 3FLG J2210.1+5925 and 3FGL J1128.7-6232, respectively. After performing a cross-correlation between different catalogs at distinct wavelengths, we found that these bowshocks are the most peculiar objects in the Fermi position ellipses. Then we computed the inverse Compton emission and fitted the Fermi data in order to test the viability of both runaway stars as potential counterparts of the two high-energy sources. We obtained very reasonable values for the fitted parameters of both stars. We also evaluated the possibility for the source 3FGL J1128.7-6232, which is positionally coincident with a H II region, to be the result of background cosmic-ray protons interacting with the matter of the cloud, as well as the probability of a pure chance association. We conclude that the gamma rays from these Fermi sources might be produced in the bowshocks of the considered runaway stars. In such a case, these would be the first sources of this class ever detected at gamma rays.…
| Author details: | María de la Estrella Sanchez-AyasoORCiD, Maria Victoria del ValleORCiD, Josep MartiORCiD, G. E. Romero, Pedro Luis Luque-EscamillaORCiD |
|---|---|
| DOI: | https://doi.org/10.3847/1538-4357/aac7c7 |
| ISSN: | 0004-637X |
| ISSN: | 1538-4357 |
| Title of parent work (English): | The astrophysical journal : an international review of spectroscopy and astronomical physics |
| Publisher: | IOP Publ. Ltd. |
| Place of publishing: | Bristol |
| Publication type: | Article |
| Language: | English |
| Date of first publication: | 2018/06/28 |
| Publication year: | 2018 |
| Release date: | 2021/11/22 |
| Tag: | stars: winds, outflows |
| Volume: | 861 |
| Issue: | 1 |
| Number of pages: | 9 |
| Funding institution: | Agencia Estatal de Investigacion grant from the Spanish Ministerio de Economia y Competitividad (MINECO) [AYA 2016-76012-C3-3-P]; Consejeria de Economia, Innovacion, Ciencia y Empleo of Junta de Andalucia [FQM-322]; FEDER fundsEuropean Union (EU); Alexander von Humboldt FoundationAlexander von Humboldt Foundation; CONICETConsejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET) [PIP 0338]; [AYA 2016-76012-C3-1-P] |
| Organizational units: | Mathematisch-Naturwissenschaftliche Fakultät / Institut für Physik und Astronomie |
| DDC classification: | 5 Naturwissenschaften und Mathematik / 52 Astronomie / 520 Astronomie und zugeordnete Wissenschaften |
| 5 Naturwissenschaften und Mathematik / 53 Physik / 530 Physik | |
| Peer review: | Referiert |
| Publishing method: | Open Access / Bronze Open-Access |
