Afficher la notice abrégée

The Detection of Molecular Gas in the Outskirts of NGC 6946

hal.structure.identifierLaboratoire d'astrodynamique, d'astrophysique et d'aéronomie de bordeaux [L3AB]
hal.structure.identifierObservatoire aquitain des sciences de l'univers [OASU]
hal.structure.identifierLaboratoire d'Astrophysique de Bordeaux [Pessac] [LAB]
dc.contributor.authorBRAINE, J.
hal.structure.identifierDepartment of Physics
dc.contributor.authorFERGUSON, Annette M. N.
dc.contributor.authorBERTOLDI, Frank
hal.structure.identifierMax F. Perutz Laboratories, University Departments at the Vienna Biocenter, Institute of Microbiology and Genetics
hal.structure.identifierUniversity of Exeter
dc.contributor.authorWILSON, Christine D.
dc.date.issued2007
dc.identifier.issn0004-637X
dc.description.abstractEnWe present the results of a search for molecular gas emission via the CO line in the far outer disk of the nearby spiral, NGC 6946. The positions targeted were chosen to lie on or near previously-identified outer disk HII regions. Molecular gas was clearly detected out to 1.3 R$_{25}$, with a further tentative detection at 1.4 R$_{25}$. The CO detections show excellent agreement with the HI velocities and imply beam-averaged column densities of $0.3-9\times 10^{20}$ cm$^{-2}$ and molecular gas masses of (2-70)$\times 10^{5}$ M$_{\sun}$ per 21$''$ beam (560pc). We find evidence for an abrupt decrease in the molecular fraction at the edge of the optical disk, similar to that seen previously in the azimuthally-averaged areal star formation rate. Our observations provide new constraints on the factors that determine the presence and detectability of molecular gas in the outskirts of galaxies, and suggest that neither the HI column, the metallicity or the local heating rate alone plays a dominant role.
dc.language.isoen
dc.publisherAmerican Astronomical Society
dc.subject.engalaxies: individual (NGC 6946)—galaxies: individual (NGC 1058) — galaxies: spiral — galaxies: ISM
dc.subject.enISM: molecules
dc.subject.enradio lines: ISM
dc.title.enThe Detection of Molecular Gas in the Outskirts of NGC 6946
dc.typeArticle de revue
dc.identifier.doi10.1086/524135
dc.subject.halPhysique [physics]/Astrophysique [astro-ph]/Cosmologie et astrophysique extra-galactique [astro-ph.CO]
dc.subject.halPlanète et Univers [physics]/Astrophysique [astro-ph]
dc.identifier.arxiv0710.1863
bordeaux.journalThe Astrophysical Journal
bordeaux.pageL73-L76
bordeaux.volume669
bordeaux.issue2
bordeaux.peerReviewedoui
hal.identifierhal-00265481
hal.version1
hal.popularnon
hal.audienceInternationale
hal.origin.linkhttps://hal.archives-ouvertes.fr//hal-00265481v1
bordeaux.COinSctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:journal&rft.jtitle=The%20Astrophysical%20Journal&rft.date=2007&rft.volume=669&rft.issue=2&rft.spage=L73-L76&rft.epage=L73-L76&rft.eissn=0004-637X&rft.issn=0004-637X&rft.au=BRAINE,%20J.&FERGUSON,%20Annette%20M.%20N.&BERTOLDI,%20Frank&WILSON,%20Christine%20D.&rft.genre=article


Fichier(s) constituant ce document

FichiersTailleFormatVue

Il n'y a pas de fichiers associés à ce document.

Ce document figure dans la(les) collection(s) suivante(s)

Afficher la notice abrégée