Show simple item record

dc.contributor.authorUrquhart, J.~S.
dc.contributor.authorFigura, C.~C.
dc.contributor.authorMoore, T.~J.~T.
dc.contributor.authorCsengeri, T.
dc.contributor.authorLumsden, S.~L.
dc.contributor.authorPillai, T.
dc.contributor.authorThompson, M.~A.
dc.contributor.authorEden, D.~J.
dc.contributor.authorMorgan, L.~K.
dc.date.accessioned2017-07-10T14:56:09Z
dc.date.available2017-07-10T14:56:09Z
dc.date.issued2015-10-01
dc.identifier.citationUrquhart , J S , Figura , C C , Moore , T J T , Csengeri , T , Lumsden , S L , Pillai , T , Thompson , M A , Eden , D J & Morgan , L K 2015 , ' The RMS survey: ammonia mapping of the environment of massive young stellar objects ' , Monthly Notices of the Royal Astronomical Society , vol. 452 , no. 4 , pp. 4029-4053 . https://doi.org/10.1093/mnras/stv1514
dc.identifier.issn0035-8711
dc.identifier.otherPURE: 9729875
dc.identifier.otherPURE UUID: cea7b04b-46fe-41c3-af5e-e09612165e72
dc.identifier.otherBibtex: urn:86e77c3f2d7f9837696ccb9d92561ee5
dc.identifier.otherScopus: 84940118505
dc.identifier.otherORCID: /0000-0001-5392-909X/work/42466475
dc.identifier.urihttp://hdl.handle.net/2299/18852
dc.descriptionThis article has been accepted for publication in Monthly Notices of the Royal Astronomical Society. © 2015 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society. Available online at: https://academic.oup.com/mnras/article-lookup/doi/10.1093/mnras/stv1514
dc.description.abstractWe present the results of ammonia observations towards 66 massive star forming regions identified by the Red Midcourse Space Experiment Source survey. We have used the Green Bank Telescope and the K-Band Focal Plane Array to map the ammonia (NH3) (1,1) and (2,2) inversion emission at a resolution of 30 arcsec in 8 arcmin regions towards the positions of embedded massive star formation. We have identified a total of 115 distinct clumps, approximately two-thirds of which are associated with an embedded massive young stellar object or compact H II region, while the others are classified as quiescent. There is a strong spatial correlation between the peak NH3 emission and the presence of embedded objects. We derive the spatial distribution of the kinetic gas temperatures, line widths, and NH3 column densities from these maps, and by combining these data with dust emission maps we estimate clump masses, H2 column densities and ammonia abundances. The clumps have typical masses of ˜1000 M⊙ and radii ˜0.5 pc, line widths of ˜2 km s-1 and kinetic temperatures of ˜16-20 K. We find no significant difference between the sizes and masses of the star-forming and quiescent subsamples; however, the distribution maps reveal the presence of temperature and line width gradients peaking towards the centre for the star-forming clumps while the quiescent clumps show relatively uniform temperatures and line widths throughout. Virial analysis suggests that the vast majority of clumps are gravitationally bound and are likely to be in a state of global free fall in the absence of strong magnetic fields. The similarities between the properties of the two subsamples suggest that the quiescent clumps are also likely to form massive stars in the future, and therefore provide an excellent opportunity to study the initial conditions of massive pre-stellar and protostellar clumps.en
dc.format.extent25
dc.language.isoeng
dc.relation.ispartofMonthly Notices of the Royal Astronomical Society
dc.rightsOpen
dc.subjectstars: early-type, stars: formation, ISM: molecules, radio lines: ISM
dc.titleThe RMS survey: ammonia mapping of the environment of massive young stellar objectsen
dc.contributor.institutionCentre for Astrophysics Research
dc.contributor.institutionSchool of Physics, Astronomy and Mathematics
dc.description.statusPeer reviewed
dc.description.versiontypeFinal Published version
dcterms.dateAccepted2015-10-01
rioxxterms.versionVoR
rioxxterms.versionofrecordhttps://doi.org/10.1093/mnras/stv1514
rioxxterms.typeJournal Article/Review
herts.preservation.rarelyaccessedtrue
herts.rights.accesstypeOpen


Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record