Show simple item record

dc.contributor.authorDrew, J. E.
dc.contributor.authorHerrero, A.
dc.contributor.authorMohr-Smith, M.
dc.contributor.authorMonguio, M.
dc.contributor.authorWright, N. J.
dc.contributor.authorKupfer, T.
dc.contributor.authorNapiwotzki, R.
dc.date.accessioned2019-01-16T15:15:01Z
dc.date.available2019-01-16T15:15:01Z
dc.date.issued2018-10-21
dc.identifier.citationDrew , J E , Herrero , A , Mohr-Smith , M , Monguio , M , Wright , N J , Kupfer , T & Napiwotzki , R 2018 , ' Massive stars in the hinterland of the young cluster, Westerlund 2 ' , Monthly Notices of the Royal Astronomical Society: Letters , vol. 480 , no. 2 , pp. 2109–2124 . https://doi.org/10.1093/mnras/sty1905
dc.identifier.issn1745-3925
dc.identifier.otherPURE: 15142343
dc.identifier.otherPURE UUID: f40690e5-3c07-49da-b219-a908df3e166b
dc.identifier.otherArXiv: http://arxiv.org/abs/1807.06486v1
dc.identifier.otherScopus: 85054709098
dc.identifier.urihttp://hdl.handle.net/2299/20978
dc.descriptionAccepted for publication in MNRAS, 13 July 2018. 16 pages, plus one-page table in an appendix.
dc.description.abstractAn unsettled question concerning the formation and distribution of massive stars is whether they must be born in massive clusters and, if found in less dense environments, whether they must have migrated there. With the advent of wide-area digital photometric surveys, it is now possible to identify massive stars away from prominent Galactic clusters without bias. In this study we consider 40 candidate OB stars found in the field around the young massive cluster, Westerlund 2, by Mohr-Smith et al.: these are located inside a box of 1.5 × 1.5 deg 2 and are selected on the basis of their extinctions and K magnitudes.We present VLT/X-shooter spectra of two of the hottest O stars, respectively 11 and 22 arcmin from the centre of Westerlund 2. They are confirmed as O4V stars, with stellar masses likely to be in excess of 40 M ·. Their radial velocities relative to the non-binary reference object, MSP 182, in Westerlund 2 are -29.4 ± 1.7 and -14.4 ± 2.2 km s -1, respectively. Using Gaia DR2 proper motions we find that between 8 and 11 early O/WR stars in the studied region (including the two VLT targets, plus WR 20c and WR 20aa) could have been ejected fromWesterlund 2 in the last one million years. This represents an efficiency of massive-star ejection of up to ~ 25 per cent. On sky, the positions of these stars and their proper motions show a near N-S alignment. We discuss the possibility that these results are a consequence of prior sub-cluster merging combining with dynamical ejection.en
dc.format.extent16
dc.language.isoeng
dc.relation.ispartofMonthly Notices of the Royal Astronomical Society: Letters
dc.rightsOpen
dc.subjectGalaxy: structure
dc.subjectOpen clusters and associations: individual: Westerlund 2
dc.subjectStars: early-type
dc.subjectSurveys
dc.subjectAstronomy and Astrophysics
dc.subjectSpace and Planetary Science
dc.titleMassive stars in the hinterland of the young cluster, Westerlund 2en
dc.contributor.institutionSchool of Physics, Astronomy and Mathematics
dc.contributor.institutionCentre for Astrophysics Research
dc.description.statusPeer reviewed
dc.identifier.urlhttp://www.scopus.com/inward/record.url?scp=85054709098&partnerID=8YFLogxK
dc.relation.schoolSchool of Physics, Astronomy and Mathematics
dc.description.versiontypeFinal Published version
dcterms.dateAccepted2018-10-21
rioxxterms.versionVoR
rioxxterms.versionofrecordhttps://doi.org/10.1093/mnras/sty1905
rioxxterms.licenseref.uriOther
rioxxterms.typeJournal Article/Review
herts.rights.accesstypeOpen


Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record