J/ApJ/738/27ivo://CDS.VizieR/J/ApJ/738/27doi:10.26093/cds/vizier.17380027CDSBalser D.S.Rood R.T.Bania T.M.Anderson L.D.2017-11-06T12:23:47Z2013-02-13T15:00:30ZCDS support team

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

cds-question@unistra.frh-ii-regionsmilky-way-galaxyradio-astronomyradio-continuum-emissionThe distribution of metals in the Galaxy provides important information about galaxy formation and evolution. HII regions are the most luminous objects in the Milky Way at mid-infrared to radio wavelengths and can be seen across the entire Galactic disk. We used the National Radio Astronomy Observatory (NRAO) Green Bank Telescope to measure radio recombination line (RRL) and continuum emission in 81 Galactic HII regions. We calculated LTE electron temperatures using these data. In thermal equilibrium metal abundances are expected to set the nebular electron temperature with high abundances producing low temperatures. Our HII region distribution covers a large range of Galactocentric radius (5-22kpc) and samples the Galactic azimuth range 330-60{deg}. Using our highest quality data (72 objects) we derived an O/H Galactocentric radial gradient of -0.0383+/-0.0074dex/kpc. Combining these data with a similar survey made with the NRAO 140 Foot telescope we get a radial gradient of -0.0446+/-0.0049dex/kpc for this larger sample of 133 nebulae.2011ApJ...738...27Bhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/738/27CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toVIII/58 : A Survey of Radio H II Regions in the Northern Sky (Lockman+ 1989)J/ApJS/194/32 : The HII Region Discovery Survey (HRDS). II. (Anderson+, 2011)J/ApJ/690/706 : Distances of Galactic HII regions (Anderson+, 2009)J/A+A/464/909 : JHK photometry near IRAS 06145+1455 (Brand+, 2007)J/ApJS/165/338 : Radio recombination lines in HII regions (Quireza+, 2006)J/ApJ/653/1226 : Physical properties of galactic HII regions (Quireza+, 2006)J/ApJS/162/346 : Abundance gradients in the Galaxy (Rudolph+, 2006)J/ApJ/582/756 : Velocities of HII regions (Kolpak+, 2003)J/A+A/397/213 : Galactic HII regions (Paladini+, 2003)J/ApJ/488/224 : 4.85 GHz fluxes of H II regions (Kuchar+ 1997)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/738/27https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/738/27http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/738/27https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/738/27https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/738/27http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/738/27GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/738/27/HIIregions (Galactic HII regions: propertiies (table1) and radio continuum parameters (table3))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/738/27/HIIregions?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/738/27/HIIregions?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/738/27/HIIregions?GETtext/xml+votable180.050000true270.554219-22.464420.0055555555555555566/1297 1330 1781 1839 1848 1930 3290 3303 3606 3639 3649 3718 3730 14293 14304 14306 14307 14311 14314 14317 14344 14355 14358 14359 14406 14409 14430 14453 14621 14622 14624 14644 14666 14671 14682 14683 14688 14690 14691 14692 14693 14697 14704 14716 15368 15461 15473 20849 21439 21458 21504 21550 21641 21679 22078 22080 23645 23764 23969 24554 28918 30262 30315 30318 30328 30341 30423 30594 30624 30644 30645 30694 30718 39804https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/738/27?format=asciiRadiodefaultJ/ApJ/738/27/HIIregionsGalactic HII regions: propertiies (table1) and radio continuum parameters (table3)SimbadNameSimbad column added by the CDSmeta.idcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameHII region namemeta.id;meta.maincharprimaryGLON[7/244] Galactic longitudedegpos.galactic.lonGLAT[-20/3.5] Galactic latitudedegpos.galactic.latfloatRAB1950Hour of right ascension (B1950)pos.eq.ra;meta.mainDEB1950Degree of declination (B1950)pos.eq.dec;meta.mainAz[0/360] Galactocentric azimuthdegpos.az.azi;pos.galactocentricfloatRgal[4.7/21.9] Galactocentric radiuskpcpos.distance;pos.galactocentricfloatdsun[0.3/30.3] Distance from the Sun (1)kpcpos.distance;pos.heliocentricfloaty[0.017/0.135] Helium abundance ratio by numberphys.abund.Yfloate_yy uncertaintystat.error;pos.cartesian.yfloatTe[5229/14578] LTE electron temperatureKphys.temperature.electron;phys.electroninte_TeTe uncertaintyKstat.errorintRCatCross-match with Kuchar+, 1997, Cat. J/ApJ/488/224, within 10"meta.ref.urlintnullableSCatCross-match with sample selection catalogs: VIII/58 and J/ApJS/194/32, within 5"meta.ref.urlintnullableTcRAPeak intensity (T_C_) for the RA scansKphot.fluxfloate_TcRATcRA uncertaintyKstat.errorfloatTheRAFWHM angular width ({Theta}) for the RA scansarcminphys.angSizefloate_TheRATheRA uncertaintyarcminstat.errorfloatTcDEPeak intensity (T_C_) for the DEC scansKphot.fluxfloate_TcDETcDE uncertaintyKstat.errorfloatTheDEFWHM angular width ({Theta}) for the DEC scansarcminphys.angSizefloate_TheDETheDE uncertaintyarcminstat.errorfloatTc[0.092/110.79] Average peak intensity (T_C_)Kphot.flux;stat.meanfloate_TcTc uncertaintyKstat.errorfloatTheta[1.3/7.6] Average FWHM angular width ({Theta})arcminphys.angSizefloate_ThetaTheta uncertaintyarcminstat.error;pos.posAngfloatQF[A-D] Data quality (A=excellent; D=poor) (G1)meta.code.qualchar_RA.icrsRight ascension (ICRS) (computed by VizieR, not part of the original data)pos.eq.ranullableindexed_DE.icrsDeclination (ICRS) (computed by VizieR, not part of the original data)pos.eq.decnullableindexedJ/ApJ/738/27/table2Radio recombination line (RRL) parameters of Galactic HII regionsElAtom (C, H or He)phys.atmol.ionStagecharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameHII region namemeta.id;obs.fieldcharTL[2.31/9728.44] Peak intensity (T_L_)mKspect.line.intensityfloate_TLTL uncertaintymKstat.errorfloatDelV[1.9/42.2] FWHM line width ({Delta}V)km/sspect.line.widthfloate_DelVDelV uncertaintykm/sstat.errorfloatVlsr[-107.36/89.84] LSR velocitykm/sphys.veloc;pos.lsrfloate_VlsrVlsr uncertaintykm/sstat.error;phys.veloc;pos.lsrfloatTint[2.4/108.8]? Total integration time (1)htime.epochfloatnullablerms? root-mean-square noise of the line free regionmKstat.stdev;instr.det.noisefloatnullableQF[A-D] Data quality (A=excellent; D=poor) (G1)meta.code.qualchar