J/other/RAA/24.Iivo://CDS.VizieR/J/other/RAA/24.I5007CDSWang B.-R.Li D.Goldsmith P.F.Wu J.Tsai C.-W.Quan D.Zhang X.,Wang J.Melnick G.J.Li J.-Z.Fuller G.A.Xie J.2025-09-01T07:18:35Z2025-08-28T12:57:42ZCDS support team

CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France

cds-question@unistra.frstar-forming-regionsmillimeter-astronomysubmillimeter-astronomyastrometryMolecular oxygen abundance is a key parameter in understanding the chemical network of the interstellar medium. We estimate the molecular oxygen column density and abundance for a sample of Galactic massive star formation regions based on observations from the Submillimiter Wave Astronomy Satellite (SWAS) survey. We obtained an averaged O_2_ spectrum based on this sample using the (SWAS) survey data (O_2_, 487.249GHz, N=3-1, J=3-2). No emission or absorption feature is seen around the supposed central velocity with a total integration time of t_total_=8.67x10^3^hr and an rms noise per channel of 1.45mK. Assuming a kinetic temperature T_kin_=30K, we derive the 3{sigma} upper limit of the O_2_ column density to be 3.3x10^15^cm^-2^, close to the lowest values reported in Galactic massive star formation regions in previous studies. The corresponding O_2_ abundance upper limit is 6.7x10^-8^, lower than all previous results based on SWAS observations and is close to the lowest reported value in massive star formation regions. On a galactic scale, our statistical results confirm a generally low O_2_ abundance for Galactic massive star formation regions. This abundance is also lower than results reported in extragalactic sources.2024RAA....24i5007Whttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/other/RAA/24.I5007CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/other/RAA/24.I5007https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/other/RAA/24.I5007http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/other/RAA/24.I5007https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/other/RAA/24.I5007https://vizier.iucaa.in/viz-bin/votable?-source=J/other/RAA/24.I5007http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/other/RAA/24.I5007GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/other/RAA/24.I5007/tabled1 (Massive Star Formation Regions Analyzed in the Paper)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/other/RAA/24.I5007/tabled1?https://vizier.iucaa.in/viz-bin/conesearch/J/other/RAA/24.I5007/tabled1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/other/RAA/24.I5007/tabled1?GETtext/xml+votable180.050000true344.0762.030.0055555555555555566/3198 3649 14304 14315 14317 14353 14358 14621-14622 14624 14655 15667 15673 15681 15683 21447 21458 22243 23637 23969 23982 28891 29091 29097 29101 29116 29535 30241 30269 30318 30618 30691 30694 37752 37850 37872 37884 37886 37923 41778 41812 42172 42212 42456-42457 43013https://cdsarc.cds.unistra.fr/viz-bin/moc/J/other/RAA/24.I5007?format=asciiMillimeterdefaultJ/other/RAA/24.I5007/tabled1Massive Star Formation Regions Analyzed in the PaperrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSourceSource namemeta.id;meta.maincharttotalOverall total integration time (on+off)htime.expofloatoRARelative right ascensionarcsecpos.eq.ra;arith.difffloatoDERelative declinationarcsecpos.eq.dec;arith.difffloatRAJ2000Reference right ascension (J2000)degpos.eq.ra;meta.mainDEJ2000Reference declination (J2000)degpos.eq.dec;meta.mainGLONGalactic longitudedegpos.galactic.lonGLATGalacitc latitudedegpos.galactic.latfloat