Understanding the physical state of hot plasma formed through stellar wind collision in WR140 using high-resolution X-ray spectroscopy
dc.contributor.author | Miyamoto, Asca | |
dc.contributor.author | Sugawara, Yasuharu | |
dc.contributor.author | Maeda, Yoshitomo | |
dc.contributor.author | Ishida, Manabu | |
dc.contributor.author | Hamaguchi, Kenji | |
dc.contributor.author | Corcoran, Michael | |
dc.contributor.author | Russell, Christopher M P | |
dc.contributor.author | Moffat, Anthony F J | |
dc.date.accessioned | 2022-06-10T14:26:03Z | |
dc.date.available | 2022-06-10T14:26:03Z | |
dc.date.issued | 2022-05-10 | |
dc.description.abstract | We analyse a series of XMM–Newton RGS data of the binary Wolf–Rayet star WR140 that encompasses one entire orbit. We find that the RGS detects X-rays from optically thin thermal plasma only during orbital phases when the companion O star is on the near side of the WR star. Although such X-rays are believed to be emitted from the shock cone formed through collision of the stellar winds, temperature and density profiles of the plasma along the cone have not been measured observationally. We find that the temperature of the plasma producing Ne emission lines is 0.4–0.8 keV, using the intensity ratio of Kα lines from He-like and H-like Ne. We also find, at orbital phases 0.816 and 0.912, that the electron number density in the Ne line-emission site is approximately 1012 cm−3 from the observed intensity ratios f/r and i/r of the He-like triplet. We calculated the shock cone shape analytically, and identify the distance of the Ne line-emission site from the shock stagnation point to be 0.9–8.9 × 1013 cm using the observed ratio of the line-of-sight velocity and its dispersion. This means that we will be able to obtain the temperature and density profiles along the shock cone with emission lines from other elements. We find that the photoexcitation rate by the O star is only 1.3–16.4 per cent of that of the collisional excitation at orbital phase 0.816. This implies that our assumption that the plasma is collisionally excited is reasonable, at least at this orbital phase. | en_US |
dc.description.sponsorship | The material is based upon work supported by NASA under award number 80GSFC21M0002. KH is supported by the NASA grants 15-NUSTAR215-0026, 80NSSC19K0690, JPL grant 001287-00001. This research made use of the Astrophysics Data System and the HEASARC archive. This research was partially supported by the Ministry of Education, Culture, Sports, Science and Technology (MEXT), Grant-in-Aid Nos.19K21886 and 20H00175. AFJM is grateful for financial aid from NSERC (Canada). CMPR acknowledges support from the National Science Foundation under Grant No. AST-1747658. The authors are grateful to Dr. Ian Stevens for a number of his useful comments. | en_US |
dc.description.uri | https://academic.oup.com/mnras/advance-article-abstract/doi/10.1093/mnras/stac1289/6583294 | en_US |
dc.format.extent | 14 pages | en_US |
dc.genre | journal articles | en_US |
dc.genre | postprints | en_US |
dc.identifier | doi:10.13016/m2wpyz-smmz | |
dc.identifier.citation | Asca Miyamoto, Yasuharu Sugawara, Yoshitomo Maeda, Manabu Ishida, Kenji Hamaguchi, Michael Corcoran, Christopher M P Russell, Anthony F J Moffat, Understanding the physical state of hot plasma formed through stellar wind collision in WR140 using high-resolution X-ray spectroscopy, Monthly Notices of the Royal Astronomical Society, 2022;, stac1289, https://doi.org/10.1093/mnras/stac1289 | en_US |
dc.identifier.uri | https://doi.org/10.1093/mnras/stac1289 | |
dc.identifier.uri | http://hdl.handle.net/11603/24886 | |
dc.language.iso | en_US | en_US |
dc.publisher | Oxford University Press | en_US |
dc.relation.isAvailableAt | The University of Maryland, Baltimore County (UMBC) | |
dc.relation.ispartof | UMBC Center for Space Sciences and Technology | |
dc.relation.ispartof | UMBC Faculty Collection | |
dc.rights | This work was written as part of one of the author's official duties as an Employee of the United States Government and is therefore a work of the United States Government. In accordance with 17 U.S.C. 105, no copyright protection is available for such works under U.S. Law. | en_US |
dc.rights | Public Domain Mark 1.0 | * |
dc.rights.uri | http://creativecommons.org/publicdomain/mark/1.0/ | * |
dc.title | Understanding the physical state of hot plasma formed through stellar wind collision in WR140 using high-resolution X-ray spectroscopy | en_US |
dc.type | Text | en_US |
dcterms.creator | https://orcid.org/0000-0001-7515-2779 | en_US |