J/ApJ/887/114ivo://CDS.VizieR/J/ApJ/887/114doi:10.26093/cds/vizier.18870114CDSWenger T.V.Balser D.S.Anderson L.D.Bania T.M.2024-02-06T11:29:14Z2023-04-04T12:49:59ZCDS support team

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

cds-question@unistra.frh-ii-regionsmilky-way-galaxyinterstellar-mediumradio-continuum-emissionsurveysinfrared-sourcesThe metallicity structure of the Milky Way disk stems from the chemodynamical evolutionary history of the Galaxy. We use the National Radio Astronomy Observatory Karl G. Jansky Very Large Array to observe ~8-10GHz hydrogen radio recombination line and radio-continuum emission toward 82 Galactic HII regions. We use these data to derive the electron temperatures and metallicities for these nebulae. Since collisionally excited lines from metals (e.g., oxygen, nitrogen) are the dominant cooling mechanism in HII regions, the nebular metallicity can be inferred from the electron temperature. Including previous single-dish studies, there are now 167 nebulae with radio-determined electron temperature and either parallax or kinematic distance determinations. The interferometric electron temperatures are systematically 10% larger than those found in previous single-dish studies, likely due to incorrect data analysis strategies, optical depth effects, and/or the observation of different gas by the interferometer. By combining the interferometer and single-dish samples, we find an oxygen abundance gradient across the Milky Way disk with a slope of -0.052+/-0.004dex/kpc. We also find significant azimuthal structure in the metallicity distribution. The slope of the oxygen gradient varies by a factor of ~2 when Galactocentric azimuths near ~30{deg} are compared with those near ~100{deg}. This azimuthal structure is consistent with simulations of Galactic chemodynamical evolution influenced by spiral arms.2019ApJ...887..114Whttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/887/114CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toVIII/58 : A Survey of Radio H II Regions in the Northern Sky (Lockman+ 1989)J/ApJS/165/338 : Radio recombination lines in HII regions (Quireza+, 2006)J/AJ/132/902 : Abundances of 54 Cepheids (Luck+, 2006)J/ApJ/653/1226 : Physical properties of galactic HII regions (Quireza+, 2006)J/ApJ/699/1153 : Kinematic dist. to GRS molecular clouds (Roman-Duval+, 2009)J/ApJ/720/1055 : VBLA observations of W51 Main/South (Sato+, 2010)J/ApJS/194/32 : The HII Region Discovery Survey (HRDS). II. (Anderson+, 2011)J/ApJ/738/27 : Galactic HII regions RRL and continuum data (Balser+, 2011)J/MNRAS/420/1656 : RMS compact HII regions distances (Urquhart+, 2012)J/ApJ/754/62 : HRDS III. HII region kinematic distances (Anderson+, 2012)J/ApJ/783/130 : Parallaxes of high mass star forming regions (Reid+, 2014)J/ApJS/212/1 : The WISE catalog of Galactic HII regions (Anderson+, 2014)J/MNRAS/444/3301 : Oxygen abundance in Galactic disc Cepheids (Korotin+, 2014)J/ApJ/806/199 : RRL & continuum data of 21 Gal. H II regions (Balser+, 2015)J/ApJ/810/42 : Hydrogen RRL parameters of H II regions (Anderson+, 2015)J/ApJS/221/26 : Radio observations of Gal. WISE HII regions (Anderson+, 2015)J/A+A/587/A70 : CALIFA face-on spiral gal. oxygen (Sanchez-Menguiano+, 2016)J/A+A/588/A97 : Continuum sources from the THOR survey (Bihr+, 2016)J/A+A/597/A30 : Seismology & spectrosc. of CoRoGEE red giants (Anders+, 2017)J/ApJS/234/33 : A GBT survey of large Galactic HII regions (Anderson+, 2018)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/887/114https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/887/114http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/887/114https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/887/114https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/887/114http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/887/114GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/887/114/table1 (Survey targets)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/887/114/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/887/114/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/887/114/table1?GETtext/xml+votable180.050000true270.13125-24.0719170.005555555555555556Cone search capability for table J/ApJ/887/114/table4 (Continuum data products)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/887/114/table4?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/887/114/table4?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/887/114/table4?GETtext/xml+votable180.050000true270.12681-24.066190.005555555555555556Cone search capability for table J/ApJ/887/114/table5 (Radio recombination line (RRL) data products)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/887/114/table5?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/887/114/table5?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/887/114/table5?GETtext/xml+votable180.050000true271.54731-20.527620.005555555555555556Cone search capability for table J/ApJ/887/114/table6 (HII region distances and properties)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/887/114/table6?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/887/114/table6?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/887/114/table6?GETtext/xml+votable180.050000true266.83435-28.385790.0055555555555555565/3672 7578 6/1297 1330 1781 1839 1848 1930 1962 3070-3071 3268 3290 3302 3309 3311 3606 3639 3649 3717-3718 3730 3755 14293 14304 14306-14307 14311 14314 14317 14344 14355 14358-14359 14364-14366 14389 14406 14409 14430 14453 14603 14620-14622 14624 14626 14640-14642 14644 14667 14682-14683 14692-14693 14697 14704 14716 15368 15390 15430 15448 15457-15458 15461 15473 15626 15642 20849 21439 21458 21504 21550 21641 21657 21679 22078 22080 22208 23645 23764 23969 23982 24554 28830-28831 28890 28897 28912 28918 29091 29096 29101 29114 29116 29118 29463 29504-29505 29507-29508 29510-29511 29515 29522 29529 29532-29533 29535 30218-30219 30240-30241 30244-30245 30253 30256 30258-30259 30262 30267-30269 30318-30319 30328 30330 30341 30417 30419-30420 30422-30423 30592 30594 30600 30604 30616 30618-30619 30622 30624 30628 30640-30641 30644-30645 30694-30695 30697 30701 30715 30718 32081 32085 39386 39804 42379 42391 42398 42436 42438 42449 42451 42455-42456 42460 42462https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/887/114?format=asciiInfraredRadiodefaultJ/ApJ/887/114/table1Survey targetsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameField identifier (GLLL.lll+BB.bbb) (G1)meta.id;meta.maincharprimaryPIDThe VLA project in which the HII region was observed (13A-030 is the pilot survey and 15B-178 is the main survey)meta.id;obscharRAJ2000WISE IR hour of right ascension (J2000)pos.eq.ra;meta.mainDEJ2000WISE IR degree of declination (J2000)pos.eq.dec;meta.mainRadIR[21/1541] The WISE infrared radius, R_IR_arcsecphys.angSize;em.IRfloatS9GHz[2/3357] The estimated 9GHz RRL flux densitymJy/beamphot.flux.density;em.radio.6-12GHzfloate_S9GHz[0.04/27] S9GHz uncertaintymJy/beamstat.errorfloatTelOriginal RRL detection telescopeinstr.telcharRefReference for the original RRL detection (see refs.dat file)meta.ref;pos.framecharSL/SC[0.0423/0.1817]? The previously measured RRL-to-continuum brightness ratio, S_L_/S_C_phot.flux;arith.ratio;em.radio.6-12GHzfloatnullablee_SL/SC[0.0003/0.007]? SL/SC uncertaintystat.errorfloatnullableTe[5335/14578]? The derived electron temperatureKphys.temperature.electron;phys.electronintnullablee_Te[47/462]? Te uncertaintyKstat.errorintnullabler_TeReference for the RRL-to-continuum brightness ratio and electron temperature (see refs.dat file)meta.ref;pos.framecharWCatDisplay data from the WISE cat. of Galactic HII regions (Anderson+, 2014, J/ApJS/212/1)meta.ref.urlcharJ/ApJ/887/114/table4Continuum data productsNameName of the HII region (GLLL.lll+BB.bbb) (G1)meta.id;meta.maincharprimary_RAPositions from the WISE cat. (Anderson+, 2014, J/ApJS/212/1) (right ascension part)degpos.eq.ra;meta.main_DEPositions from the WISE cat. (Anderson+, 2014, J/ApJS/212/1) (declination part)degpos.eq.dec;meta.mainrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintVc[8898/8964.1] the MS-MFS synthesized frequency of the combined continuum spectral windowsMHzem.freqfloatScP[1/7191.1] the peak continuum flux density, S_C_^P^mJy/beamphot.flux.density;em.radio.6-12GHzfloate_ScP[0.02/150] ScP uncertaintymJy/beamstat.errorfloatQFcPQuality factor for the peak flux density (1)meta.code.qualcharTapPthe peak flux density was measured using the non-tapered ("N") or uv-tapered ("Y") imagemeta.codecharScT[0.04/11723] the total flux density within the watershed region, S_C_^T^mJyphot.flux.density;em.radio.6-12GHzdoublee_ScT[0.07/399] ScT uncertaintymJystat.errorfloatQFcTQuality factor for the total flux density (1)meta.code.qualcharTapTThe total flux density was measured using the non-tapered ("N") or uv-tapered ("Y") imagemeta.codecharWCatDisplay data from the WISE cat. of Galactic HII regions (Anderson+, 2014, J/ApJS/212/1)meta.ref.urlcharJ/ApJ/887/114/table5Radio recombination line (RRL) data productsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameName of the HII region (GLLL.lll+BB.bbb) (G1)meta.id;meta.maincharprimaryVl[8542.6/8974.4] The weighted average frequency of the <Hn{alpha}> spectrum (1)MHzem.freqfloatSlP[1.7/1098]? Amplitude of the Gaussian fit to the spectrum extracted from the location of peak continuum brightness, S_L_^P^mJy/beamphot.flux.density;em.radio.6-12GHzfloatnullablee_SlP[0.2/3.1]? SlP uncertaintymJy/beamstat.errorfloatnullablermsP[0.6/11.8]? The spectral rms at this positionmJy/beamstat.stdevfloatnullableVlsrP[-87.5/100.4]? Center LSR velocity of the fitted Gaussiankm/sphys.veloc;pos.lsrfloatnullableSimbadSimbad column added by the CDSmeta.ref.urlchare_VlsrP[0/2.2]? VlsrP uncertaintykm/sstat.errorfloatnullabledelVP[12/39]? FWHM line width of the fitted Gaussian, {Delta}V^P^km/sspect.line.widthfloatnullablee_delVP[0.1/7]? delVP uncertaintykm/sstat.errorfloatnullableTapPThe spectrum was extracted from the non-tapered ("N") or uv-tapered ("Y") imagemeta.codecharSlT[1.7/2080]? Amplitude of the Gaussian fit to the spectrum summed within the watershed regionmJyphot.flux.density;em.radio.6-12GHzfloatnullablee_SlT[0.03/6]? SlT uncertaintymJystat.errorfloatnullablermsT[0.1/22.1]? The spectral rms in this regionmJystat.stdevfloatnullableVlsrT[-97.7/101]? Center LSR velocity of the fitted Gaussiankm/sphys.veloc;pos.lsrfloatnullablee_VlsrT[0/4.5]? VlsrT uncertaintykm/sstat.errorfloatnullabledelVT[13.5/40]? FWHM line width of the fitted Gaussiankm/sspect.line.widthfloatnullablee_delVT[0.1/22]? delVT uncertaintykm/sstat.errorfloatnullableTapTHe spectrum was extracted from the non-tapered ("N") or uv-tapered ("Y") imagemeta.codecharWCatDisplay data from the WISE cat. of Galactic HII regions (Anderson+, 2014, J/ApJS/212/1)meta.ref.urlchar_RAPositions from the WISE cat. (Anderson+, 2014, J/ApJS/212/1) (right ascension part)degpos.eq.ra;meta.main_DEPositions from the WISE cat. (Anderson+, 2014, J/ApJS/212/1) (declination part)degpos.eq.dec;meta.mainJ/ApJ/887/114/table6HII region distances and propertiesNameName of the HII region (GLLL.lll+BB.bbb) (G1)meta.id;meta.maincharprimaryTe[4061/14189] Derived electron temperatureKphys.temperature.electron;phys.electroninte_Te[19/2932] Te uncertaintyKstat.errorintTypeSource type (1)meta.codecharTapTaper column identifying which data cube is used ("N" for non-tapered and "Y" for uv-tapered)meta.codecharDist[0.09/19.5]? HII region distance (see Section 5.4)kpcpos.distancefloatnullablee_Dist[0/1.47]? Lower uncertainty on Distkpcstat.errorfloatnullableE_Dist? Upper uncertainty on Distkpcstat.error;stat.maxfloatnullablef_DistFlag on Dist (2)meta.codecharRad[0.2/15.2]? Radiuskpcphys.size.radiusfloatnullablee_Rad[0/1.31]? Lower uncertainty on Radkpcstat.errorfloatnullableE_Rad? Upper uncertainty on Radkpcstat.error;stat.maxfloatnullablef_RadFlag on Rad (2)meta.codecharMethDistance method (3)meta.codecharr_DistReference on Dist (see refs.dat file)meta.ref;pos.framecharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintTelTelescope used for the observationinstr.setupcharSL/SC[0.04/0.3] Measured RRL-to-continuum flux ratiophot.flux;arith.ratio;em.radio.6-12GHzfloate_SL/SC[0.0002/0.04] SL/SC uncertaintystat.errorfloatdelV[13.5/42] RRL FWHM line widthkm/sspect.line.widthfloate_delV[0/5.6] delV uncertaintykm/sstat.errorfloatWCatDisplay data from the WISE cat. of Galactic HII regions (Anderson+, 2014, J/ApJS/212/1)meta.ref.urlchar_RAPositions from the WISE cat. (Anderson+, 2014, J/ApJS/212/1) (right ascension part)degpos.eq.ra;meta.main_DEPositions from the WISE cat. (Anderson+, 2014, J/ApJS/212/1) (declination part)degpos.eq.dec;meta.mainJ/ApJ/887/114/refsReferencesRefReference codemeta.note;meta.maincharprimaryrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintBibCodeBibcode of the referencemeta.bib.bibcodecharAuthFirst author's namemeta.bib.authorcharCommVizieR catalog designationmeta.id;meta.datasetchar