J/ApJS/244/35ivo://CDS.VizieR/J/ApJS/244/35doi:10.26093/cds/vizier.22440035CDSLu X.Mills E.A.C.Ginsburg A.Walker D.L.Barnes A.T.Butterfield N.,Henshaw J.D.Battersby C.Kruijssen J.M.D.Longmore S.N.Zhang Q.,Bally J.Kauffmann J.Ott J.Rickert M.Wang K.2021-04-27T10:59:08Z2021-02-24T11:42:58ZCDS support team

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

cds-question@unistra.frgalactic-centerstar-forming-regionsh-ii-regionsastrophysical-masersradio-astronomyradio-continuum-emissionWe present new observations of the C-band continuum emission and masers to assess high-mass (>8M_{sun}_) star formation at early evolutionary phases in the inner 200pc of the Central Molecular Zone (CMZ) of the Galaxy. The continuum observation is complete to free-free emission from stars above 10-11M_{sun}_ in 91% of the covered area. We identify 104 compact sources in the continuum emission, among which five are confirmed ultracompact HII regions, 12 are candidates of ultracompact HII regions, and the remaining 87 sources are mostly massive stars in clusters, field stars, evolved stars, pulsars, extragalactic sources, or of unknown nature that is to be investigated. We detect class II CH_3_OH masers at 23 positions, among which six are new detections. We confirm six known H_2_CO masers in two high-mass star-forming regions and detect two new H_2_CO masers toward the Sgr C cloud, making it the ninth region in the Galaxy that contains masers of this type. In spite of these detections, we find that current high-mass star formation in the inner CMZ is only taking place in seven isolated clouds. The results suggest that star formation at early evolutionary phases in the CMZ is about 10 times less efficient than expected from the dense gas star formation relation, which is in line with previous studies that focus on more evolved phases of star formation. This means that if there will be any impending, next burst of star formation in the CMZ, it has not yet begun.2019ApJS..244...35Lhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJS/244/35CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toI/345 : Gaia DR2 (Gaia Collaboration, 2018)VIII/96 : 6-GHz methanol multibeam maser catalogue (Caswell+, 2010-12)J/ApJS/74/181 : Small-diameter radiosources catalogue (Zoonematkermani+, 1990)J/ApJS/91/347 : A 5-GHz VLA Survey of the Galactic Plane (Becker+ 1994)J/MNRAS/321/77 : Large-amplitude variables near the GC (Glass+, 2001)J/ApJS/155/421 : Survey of Galactic Center region at 20cm (Yusef-Zadeh+, 2004)J/AJ/129/348 : Radio compact HII regions in the Milky Way (Giveon+, 2005)J/ApJS/165/173 : Chandra sources in Galaxy central 150pc (Muno+, 2006)J/AJ/136/2391 : GLIMPSE Extended Green Objects catalog (Cyganowski+, 2008)J/ApJS/174/481 : 2LC Compact Radio Sources in the GC (Lazio+, 2008)J/other/PASA/26.454 : Precise positions of methanol masers (Caswell, 2009)J/ApJS/181/110 : Galactic center X-ray sources (Muno+, 2009)J/ApJ/702/178 : YSOs in the central 400pc of the Galaxy (Yusef-Zadeh+, 2009)J/ApJ/699/186 : VLA observations of the Galactic center (Zhao+, 2009)J/ApJ/736/133 : Spitzer-IRS study of massive YSOs in the GC (An+, 2011)J/MNRAS/417/114 : HST/NICMOS Galactic Center survey catalogue (Dong+, 2011)J/MNRAS/416/1764 : H_2_O Southern Galactic Plane Survey (HOPS) (Walsh+, 2011)J/ApJ/766/114 : Water & methanol masers in G75.78+0.34 (Sanchez-Monge+, 2013)J/ApJS/212/1 : The WISE catalog of Galactic HII regions (Anderson+, 2014)J/A+A/563/A68 : CH_3_OH and H_2_O Galactic center masers (Chambers+, 2014)J/ApJ/799/53 : YSO/MS star models in the CMZ (Koepferl+, 2015)J/A+A/588/A97 : Continuum sources from the THOR survey (Bihr+, 2016)J/ApJS/227/10 : CH_3_OH & OH line emission from the GC (Cotton+, 2016)J/A+A/586/A50 : Central Molecular Zone H2CO temperature maps (Ginsburg+, 2016)J/ApJ/853/171 : mm point sources in extended Sgr B2 cloud (Ginsburg+, 2018)J/A+A/619/A124 : THOR survey in northern Galactic plane (Wang+, 2018)J/ApJS/235/26 : Ultradeep cat. of X-ray point sources in the GC (Zhu+, 2018)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJS/244/35https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJS/244/35http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJS/244/35https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJS/244/35https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJS/244/35http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJS/244/35GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJS/244/35/table3 (Properties of compact sources in C-band continuum)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJS/244/35/table3?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJS/244/35/table3?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJS/244/35/table3?GETtext/xml+votable180.050000true266.72425-28.31677220.005555555555555556Cone search capability for table J/ApJS/244/35/table4 (Properties of CH_3_OH masers)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJS/244/35/table4?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJS/244/35/table4?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJS/244/35/table4?GETtext/xml+votable180.050000true266.8530833-28.36198890.005555555555555556Cone search capability for table J/ApJS/244/35/table5 (Properties of H_2_CO masers)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJS/244/35/table5?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJS/244/35/table5?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJS/244/35/table5?GETtext/xml+votable180.050000true266.83275-28.37022780.005555555555555556Cone search capability for table J/ApJS/244/35/table6 (Summary of high-mass star formation indicators)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJS/244/35/table6?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJS/244/35/table6?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJS/244/35/table6?GETtext/xml+votable180.050000true266.835-28.38527780.005555555555555556Associated datahttps://cdsarc.cds.unistra.fr/assocdata/?obs_collection=J/ApJS/244/356/28825 28827 28830 28831https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJS/244/35?format=asciiRadiodefaultJ/ApJS/244/35/table3Properties of compact sources in C-band continuumNoteRemarks (3)meta.notechare_alpha[0.01/3.4] alpha uncertainty (1)stat.error;pos.eq.rafloatHSTHST Paschen-{alpha} survey (Wang+ 2010MNRAS.402..895W)meta.codecharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIDContinuum source identification (CNNN with NNN from 1 to 104)meta.id;spect.continuumcharRAJ2000Hour of right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Degree of declination (J2000)pos.eq.dec;meta.mainReff? Effective radiuspcphys.size.radiusfloatnullablef_ReffUR: Unresolved sourcemeta.codecharIpeak[0.1/27.4] Peak intensity corrected for primary-beam responsemJy/beamphot.flux.density;em.radio.3-6GHzfloate_Ipeak[0.03/1.6] Ipeak uncertaintymJy/beamstat.errorfloatFint[0.1/64.2] Integrated flux corrected for primary-beam responsemJyphot.flux.density;em.radio.3-6GHzfloate_Fint[0.03/3.4] Fint uncertaintymJystat.errorfloatalpha[-4.4/2.2] Spectral index corrected for primary-beam responsespect.indexfloatHIIWISE HII regions (Anderson+ 2014, J/ApJS/212/1)meta.id.assoccharYSOsSpitzer YSOs (Yusef-Zadeh+, 2009, J/ApJ/702/178 and An+, 2011, J/ApJ/736/133)meta.id.assoccharNH2Herschel N(H_2_) data from Battersby+ 2011A&A...535A.128Bmeta.codecharOIDCounterparts against UC HII (2)meta.id.crosscharDetIdentifiers of previous detections of compact radio continuum emission using radio interferometers (see refs.dat file)meta.id.crosscharJ/ApJS/244/35/table4Properties of CH_3_OH masersrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIDCH_3_OH maser identifier (MNN with NN from 1 to 23)meta.id;meta.maincharAssocClass II CH_3_OH masers spatially associated with known UC/HC HII regions (Reference in parentheses; see refs.dat file); column added by CDS from Note on Table 6srccharRAJ2000Hour of right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Degree of declination (J2000)pos.eq.dec;meta.mainnuPk[-57/73.5] {nu}_peak_ value (G1)km/sphys.velocfloatFpk[0.05/64] Peak flux corrected for primary beam response (Jy per channel) (G1)Jyphot.flux.density;em.radio.3-6GHzfloatFint[0.1/102.2] Integrated flux corrected for primary beam responseJy.km/sphot.flux.density;em.radio.3-6GHzfloatRefReferences (see refs.dat file)meta.refcharJ/ApJS/244/35/table5Properties of H_2_CO masersrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIDH_2_CO maser identifier (FN with N from 1 to 8)meta.id;meta.maincharRAJ2000Hour of right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Degree of declination (J2000)pos.eq.dec;meta.mainnuPk[-54.2/75.2] {nu}_peak_ value (G1)km/sphys.velocfloatFpk[0.09/1.2] Peak flux corrected for primary beam response (Jy per channel) (G1)Jyphot.flux.density;em.radio.3-6GHzfloatl_Fpk[c] Limit flag on Fpk (1)meta.code.errorcharFint[0.1/1.6] Integrated flux corrected for primary beam responseJy.km/sphot.flux.density;em.radio.3-6GHzfloatl_Fint[c] Limit flag on Fint (1)meta.code.errorcharRefReferences (see refs.dat file)meta.refcharJ/ApJS/244/35/table6Summary of high-mass star formation indicatorsSimbadNameSimbad column added by the CDSmeta.idcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRegRegion name (1)meta.id;obs.fieldcharFig[2/5]? Figure number; column added by CDSmeta.id;meta.mainintnullableNc[0/47] Number of UC/HC HII regionsmeta.numberintRefReference(s) for UC/HC HII regions (see refs.dat file)meta.ref;pos.framecharNm[0/20] Number of Class II Ch_3_OH masersmeta.numberintNu[1/58] Number of unique indicators (2)meta.numberintSFR[0.4/25] Star forming rate (3)0.001solMass.yr**-1meta.idfloatfits1Download the FITS filemeta.ref.urlcharFile1Name of the FITS file in subdirectory "fits" for the Stokes-I PB-uncorrected image (central frequency at 5.56GHz); column added by CDSmeta.id;meta.fitscharfits2Download the FITS filemeta.ref.urlcharFile2Name of the FITS file in subdirectory "fits" for the Stokes-I primary-beam-corrected image; column added by CDSmeta.id;meta.fitschar_RARight Ascension (J2000) from SIMBAD (not part of the original data)degpos.eq.ra;meta.main_DEDeclination (J2000) from SIMBAD (not part of the original data)degpos.eq.dec;meta.mainJ/ApJS/244/35/refsReferencesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRefReference codemeta.notecharBibCodeBibcode of the referencemeta.bib.bibcodecharAuthFirst author's name(s)meta.bib.authorcharCatVizieR catalogue referencemeta.id;meta.datasetchar