Show simple item record

dc.contributor.authorKruijssen, J.~M.~D.
dc.contributor.authorDale, James
dc.contributor.authorLongmore, S.~N.
dc.date.accessioned2017-07-14T09:59:25Z
dc.date.available2017-07-14T09:59:25Z
dc.date.issued2015-02-21
dc.identifier.citationKruijssen , J M D , Dale , J & Longmore , S N 2015 , ' The dynamical evolution of molecular clouds near the Galactic Centre - I. Orbital structure and evolutionary timeline ' , Monthly Notices of the Royal Astronomical Society , vol. 447 , no. 2 , pp. 1059-1079 . https://doi.org/10.1093/mnras/stu2526
dc.identifier.issn0035-8711
dc.identifier.otherPURE: 11150995
dc.identifier.otherPURE UUID: bdf2ee9c-bfec-4b1c-80f6-a7b8256636c4
dc.identifier.otherBibtex: urn:db30769d2cd69b69a23d745971c68519
dc.identifier.otherScopus: 84922553346
dc.identifier.otherORCID: /0000-0001-5252-5771/work/62751055
dc.identifier.urihttp://hdl.handle.net/2299/18945
dc.descriptionThis article has been accepted for publication in Monthly Notices of the Royal Astronomical Society. © 2014 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society.
dc.description.abstractWe recently proposed that the star-forming potential of dense molecular clouds in the Central Molecular Zone (CMZ, i.e. the central few 100 pc) of the Milky Way is intimately linked to their orbital dynamics, potentially giving rise to an absolute-time sequence of star-forming clouds. In this paper, we present an orbital model for the gas stream(s) observed in the CMZ. The model is obtained by integrating orbits in the empirically constrained gravitational potential and represents a good fit ( χ2red=2.0 χred2=2.0 ) to the observed position–velocity distribution of dense (n > several 103 cm-3) gas, reproducing all of its key properties. The orbit is also consistent with observational constraints not included in the fitting process, such as the 3D space velocities of Sgr B2 and the Arches and Quintuplet clusters. It differs from previous, parametric models in several respects: (1) the orbit is open rather than closed due to the extended mass distribution in the CMZ, (2) its orbital velocity (100–200 km s-1) is twice as high as in previous models, and (3) Sgr A* coincides with the focus of the (eccentric) orbit rather than being offset. Our orbital solution supports the recently proposed scenario in which the dust ridge between G0.253+0.016 (‘the Brick’) and Sgr B2 represents an absolute-time sequence of star-forming clouds, of which the condensation was triggered by the tidal compression during their most recent pericentre passage. We position the clouds on a common timeline and find that their pericentre passages occurred 0.30–0.74 Myr ago. Given their short free-fall times (tff ∼ 0.34 Myr), the quiescent cloud G0.253+0.016 and the vigorously star-forming complex Sgr B2 are separated by a single free-fall time of evolution, implying that star formation proceeds rapidly once collapse has been initiated. We provide the complete orbital solution, as well as several quantitative predictions of our model (e.g. proper motions and the positions of star formation ‘hotspots’). The paper is concluded with a discussion of the assumptions and possible caveats, as well as the position of the model in the Galactic context, highlighting its relation to large-scale gas accretion, the dynamics of the bar, the x2 orbital family, and the origin of the Arches and Quintuplet clusters.en
dc.format.extent21
dc.language.isoeng
dc.relation.ispartofMonthly Notices of the Royal Astronomical Society
dc.subjectstars: formation, ISM: clouds, ISM: kinematics and dynamics, Galaxy: centre, galaxies: ISM
dc.titleThe dynamical evolution of molecular clouds near the Galactic Centre - I. Orbital structure and evolutionary timelineen
dc.contributor.institutionCentre for Astrophysics Research
dc.contributor.institutionSchool of Physics, Astronomy and Mathematics
dc.description.statusPeer reviewed
rioxxterms.versionVoR
rioxxterms.versionofrecordhttps://doi.org/10.1093/mnras/stu2526
rioxxterms.typeJournal Article/Review
herts.preservation.rarelyaccessedtrue


Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record