J/ApJ/777/157ivo://CDS.VizieR/J/ApJ/777/157doi:10.26093/cds/vizier.17770157CDSHoq S.Jackson J.M.Foster J.B.Sanhueza P.Guzman A.Whitaker J.S.,Claysmith C.Rathborne J.M.Vasyunina T.Vasyunin A.2017-07-05T06:59:50Z2015-05-12T15:16:35ZCDS support team

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

cds-question@unistra.frradio-astronomyh-ii-regionsinterstellar-mediummillimeter-astronomysubmillimeter-astronomygalaxy-planesmilky-way-galaxysurveysThe chemical changes of high-mass star-forming regions provide a potential method for classifying their evolutionary stages and, ultimately, ages. In this study, we search for correlations between molecular abundances and the evolutionary stages of dense molecular clumps associated with high-mass star formation. We use the molecular line maps from Year 1 of the Millimetre Astronomy Legacy Team 90GHz (MALT90) Survey. The survey mapped several hundred individual star-forming clumps chosen from the ATLASGAL survey to span the complete range of evolution, from prestellar to protostellar to H II regions. The evolutionary stage of each clump is classified using the Spitzer GLIMPSE/MIPSGAL mid-IR surveys. Where possible, we determine the dust temperatures and H_2_ column densities for each clump from Herschel/Hi-GAL continuum data. From MALT90 data, we measure the integrated intensities of the N_2_H^+^, HCO^+^, HCN and HNC(1-0) lines, and derive the column densities and abundances of N_2_H^+^ and HCO^+^. The Herschel dust temperatures increase as a function of the IR-based Spitzer evolutionary classification scheme, with the youngest clumps being the coldest, which gives confidence that this classification method provides a reliable way to assign evolutionary stages to clumps. Both N_2_H^+^ and HCO^+^ abundances increase as a function of evolutionary stage, whereas the N_2_H^+^(1-0) to HCO^+^(1-0) integrated intensity ratios show no discernable trend. The HCN(1-0) to HNC(1-0) integrated intensity ratios show marginal evidence of an increase as the clumps evolve.2013ApJ...777..157Hhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/777/157CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/A+A/568/A41 : ATLASGAL Compact Source Catalog: 280<l<60 (Urquhart+, 2014)J/A+A/565/A75 : ATLASGAL. Dust condensations (Csengeri+, 2014)J/A+A/557/A94 : SiO and HCO+ massive molecular outflows (Sanchez-Monge+, 2013)J/A+A/549/A45 : ATLASGAL Compact Source Catalog: 330<l<21 (Contreras+, 2013)J/ApJ/756/60 : A 3mm line survey in 37 IR dark clouds (Sanhueza+, 2012)J/ApJS/197/25 : MALT90 pilot survey (Foster+, 2011)J/A+A/527/A88 : Chemistry in infrared dark clouds (Vasyunina+, 2011)J/AJ/136/2391 : GLIMPSE Extended Green Objects catalog (Cyganowski+, 2008)J/ApJ/641/389 : Millimetric observations of IRDC cores (Rathborne+, 2006)J/ApJ/639/227 : MSX IRDC candidate catalog (Simon+, 2006)J/A+A/291/943 : Protostellar cores (Ossenkopf+, 1994)http://malt90.bu.edu/ : MALT90 home pagehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/777/157https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/777/157http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/777/157https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/777/157https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/777/157http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/777/157GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/777/157/clumps (MALT90 clump parameters and derived molecular properties)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/777/157/clumps?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/777/157/clumps?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/777/157/clumps?GETtext/xml+votable180.050000true266.54-28.7118330.0055555555555555565/10542 10615 6/28802 28808 28809 28812 28824 28830 28875 28879 28897 28900 28901 28915 28918 28919 29090 29094 29097 29100 41595 41597 41599 41652 41654 41657 41658 41660 41661 41671 41673 41675 41676 41677 41681 41682 41683 41684 41685 41688 41697 41758 41759 41763 41766 41767 41770 41772 41776 41777 41778 41780 41781 41782 41802 41825 42158 42159 42172 42173 42174 42206 42207 42210 42211 42213 42214 42215 42216 42217 42224 42225 42226 42228 42229 42376 42378 42379 42381 42383 42387 42390 42391 42392 42396 42397 42398 42436 42438 42439 42441 42444 42445 42450 42451 42454 42455 42456 42457 42458 42501 42502 42512 43013 43014 43015 43021 43024 43026https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/777/157?format=asciiRadiodefaultJ/ApJ/777/157/table4Gaussian fit parameters for the 333 regionsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintMolMolecular line identifiermeta.id;meta.mainNameSource identifiermeta.idcharTrms? Root-mean-square temperature (noise in T*A)Kstat.stdevfloatnullableT*A[0.08/6.1]? Antenna temperatureKphot.antennaTempfloatnullablee_T*A[0.01/0.2]? Uncertainty in T*AKstat.errorfloatnullablesigma[0.04/0.4]? 1{sigma} uncertainty of integrated intensityK.km/sstat.error;phot.flux.density;em.radiofloatnullableInt[0.1/11.8]? Integrated Intensity over {+/-}1km/s of T*AK.km/sphot.flux.density;em.radiofloatnullableDelV[0.7/19.7]? Line width {Delta}Vkm/sspect.line.width;em.opt.Vfloatnullablee_DelV[0.02/2.2]? Uncertainty in DelVkm/sstat.errorfloatnullableVlsr[-128.3/193]? Local Standard of Rest velocity (1)km/sphys.veloc;pos.lsrfloatnullablee_Vlsr[-0/79.4]? Uncertainty in Vlsrkm/sstat.error;phys.veloc;pos.lsrfloatnullableDetDetection category (2)meta.noteJ/ApJ/777/157/clumpsMALT90 clump parameters and derived molecular propertiesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameSource identifier (GLLL.lll+BB.bbb)meta.id;meta.maincharMDisplay the Gaussian fit parameters of the molecule detectionsmeta.ref.urlcharRAJ2000[12/18] Hour of Right Ascension (J2000)pos.eq.ra;meta.mainDEJ2000[19/63] Degree of Declination (J2000)pos.eq.dec;meta.mainClassSpitzer Classification (H II; Protostellar; Quiescent or PDR=photodissociation region)src.classcharT[9/42]? TemperatureKphys.temperaturefloatnullablee_T[0.9/6]? Lower uncertainty in TKstat.errorfloatnullableE_T[1.4/9]? Upper uncertainty in TKstat.error;stat.maxfloatnullableNH2[0/100.2]? The H_2_ column density1e+22cm**-2phys.columnDensityfloatnullablee_NH2[0.01/25.1]? Uncertainty in NH21e+22cm**-2stat.error;phys.columnDensityfloatnullableOD-N2H+[0/3]? The N_2_H^+^ optical depthphys.absorption.opticalDepthfloatnullablee_OD-N2H+[0.1/3]? Uncertainty in OD-N2H+stat.errorfloatnullableOD-HCO+[3/218]? The HCO^+^ optical depthphys.absorption.opticalDepthfloatnullablee_OD-HCO+[0.4/331]? Uncertainty in OD-HCO+stat.errorfloatnullableCD-N2H+[1/158]? The N_2_H^+^ column density1e+12cm**-2phys.columnDensityfloatnullablee_CD-N2H+[0.6/29]? Uncertainty in CD-N2H+1e+12cm**-2stat.errorfloatnullableCD-HCO+[0.4/36]? The HCO^+^ column density1e+14cm**-2phys.columnDensityfloatnullablee_CD-HCO+[0.1/59]? Uncertainty in CD-HCO+1e+14cm**-2stat.errorfloatnullableA-N2H+[0/168]? The N_2_H^+^ abundancephys.abundfloatnullablee_A-N2H+[0.1/79]? Uncertainty in A-N2H+stat.errorfloatnullableA-HCO+[0.2/197]? The HCO^+^ abundancephys.abundfloatnullablee_A-HCO+[0.1/92]? Uncertainty in A-HCO+stat.errorfloatnullableDt-N2H+The N_2_H^+^ detection type (1)meta.notecharDt-HCO+The HCO^+^ detection type (1)meta.noteSimbadSimbad column added by the CDSmeta.ref.urlchar