J/ApJS/243/13ivo://CDS.VizieR/J/ApJS/243/13doi:10.26093/cds/vizier.22430013CDSLi M.Zhou J.Esimbek J.Quan D.He Y.Li Q.Zhu C.2021-02-23T10:45:30Z2020-02-06T15:37:20ZCDS support team

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

cds-question@unistra.frmolecular-cloudsstar-forming-regionsinterstellar-mediumradio-astronomyWe selected 90 massive star-forming clumps with strong N2H+(1-0), HCO+(1-0), HCN(1-0), and HNC(1-0) emission from the Millimetre Astronomy Legacy Team 90 GHz survey. We obtained Herschel data for all 90 sources and NRAO VLA Sky Survey data for 51 of them. We convolved and regridded all images to the same resolution and pixel size and derived the temperature, H2 column density, molecules' abundances and abundance, and ratios of each pixel. Our analysis yields three main conclusions. First, the abundances of N2H+, HCO+, HCN, and HNC increase when the column density decreases and the temperature increases, with spatial variations in their abundances dominated by changes in the H2 column density. Second, the abundance ratios between N2H+, HCO+, HCN, and HNC also display systemic variations as a function of the column density due to the chemical properties of these molecules. Third, the sources associated with the 20cm continuum emission can be classified into four types based on the behavior of the abundances of the four molecules considered here as a function of this emission. The variations of the first three types could also be attributed to the variation of the H2 column density.2019ApJS..243...13Lhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJS/243/13CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toVIII/65 : 1.4GHz NRAO VLA Sky Survey (NVSS) (Condon+ 1998)J/A+A/291/943 : Protostellar cores (Ossenkopf+, 1994)J/A+AS/124/205 : W3 star-forming region 345 GHz survey (Helmich+ 1997)J/A+A/527/A88 : Chemistry in infrared dark clouds (Vasyunina+, 2011)J/ApJ/756/60 : A 3mm line survey in 37 IR dark clouds (Sanhueza+, 2012)J/ApJ/777/157 : 90GHz obs. of high-mass star-forming regions (Hoq+, 2013)J/A+A/563/A97 : IRAM 30m reduced spectra of 59 sources (Gerner+, 2014)J/A+A/568/A41 : ATLASGAL Compact Source Catalog: 280<l<60 (Urquhart+, 2014)J/other/ApSS/361.191 : High-mass star forming clumps from MALT90 (Zhang+, 2016)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJS/243/13https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJS/243/13http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJS/243/13https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJS/243/13https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJS/243/13http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJS/243/13GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJS/243/13/table1 (*51 massive star-forming clumps selected from Zhang+ (2016, J/other/ApSS/361.191))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJS/243/13/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJS/243/13/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJS/243/13/table1?GETtext/xml+votable180.050000true266.2565461-28.84968890.005555555555555556Cone search capability for table J/ApJS/243/13/table2 (39 massive star-forming clumps selected from Zhang+ (2016, J/other/ApSS/361.191))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJS/243/13/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJS/243/13/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJS/243/13/table2?GETtext/xml+votable180.050000true270.0621761-24.02436190.0055555555555555565/10615 6/28802 28803 28806 28809 28811 28812 28813 28814 28824 28827 28828 28830 28852 28912 28913 28919 29091 29094 29096 29100 29101 29103 29112 29113 29115 42207 42378 42379 42381 42383 42390 42392 42397 42434 42435 42441 42444 42445 42447 42450 42454 42456 42457 42458https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJS/243/13?format=asciiRadiodefaultJ/ApJS/243/13/table1*51 massive star-forming clumps selected from Zhang+ (2016, J/other/ApSS/361.191)SimbadNameSimbad column added by the CDSmeta.idcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeq[1/90] Running sequence numbermeta.idintNameClump name from Zhang+ (2016, J/other/ApSS/361.191)meta.id;meta.maincharTypeType (only for Table 1) (1)src.classcharGroupGroup (2)meta.codecharStageEvolutionary stage from Zhang+ (2016, J/other/ApSS/361.191)src.classchar_RAPositions from Zhang+ 2016, J/other/ApSS/361.191 (right ascension part)degpos.eq.ra;meta.main_DEPositions from Zhang+ 2016, J/other/ApSS/361.191 (declination part)degpos.eq.dec;meta.mainJ/ApJS/243/13/table239 massive star-forming clumps selected from Zhang+ (2016, J/other/ApSS/361.191)SimbadNameSimbad column added by the CDSmeta.idcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeq[1/90] Running sequence numbermeta.idintNameClump name from Zhang+ (2016, J/other/ApSS/361.191)meta.id;meta.maincharGroupGroup (2)meta.codecharStageEvolutionary stage from Zhang+ (2016, J/other/ApSS/361.191)src.classchar_RAPositions from Zhang+ 2016, J/other/ApSS/361.191 (right ascension part)degpos.eq.ra;meta.main_DEPositions from Zhang+ 2016, J/other/ApSS/361.191 (declination part)degpos.eq.dec;meta.main