J/A+A/697/A190ivo://CDS.VizieR/J/A+A/697/A190doi:10.26093/cds/vizier/bc-ns/lbjaCDSLi Z.-Y.Liu X.Liu T.Qin S.-L.Goldsmith P.F.Garcia P.Peng Y.,Chen L.Jiao Y.Kou Z.Li C.Zou J.Tang M.Li S.Liu M.Garay G.,Xu F.Jiao W.Luo Q.-Y.Zhang S.Gu Q.-L.Mai X.Zhang Y.-K.Weng J.,Won Lee C.Sanhueza P.Dib S.Das S.R.Tang X.Bronfman L.Gorai P.,Tatematsu K.Liu H.-L.Yang D.Zhang Z.Shen X.2026-07-03T06:37:02Z2025-05-20T09:36:25ZCDS support team

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

cds-question@unistra.frmillimeter-astronomysubmillimeter-astronomyspectroscopymolecular-physicsHot cores represent critical astrophysical environments for high-mass star formation, distinguished by their rich spectra of organic molecular emission lines. Nevertheless, comprehensive statistical analyses of extensive hot core samples remain relatively scarce in current astronomical research. We aim to utilize high-angular-resolution molecular line data from the Atacama Large Millimeter and Submillimeter Array (ALMA) to identify hot cores, with a particular focus on weak-emission candidates, and to provide one of the largest samples of hot core candidates to date. We propose to use spectral stacking and imaging techniques of complex organic molecules (COMs) in the ALMA-ATOMS survey, including line identification and weights, segmentation of line datacubes, resampling, stacking and normalization, moment 0 maps, and data analysis, to search for hot core candidates. The molecules involved include CH_3_OH, CH_3_OCHO, C_2_H_5_CN, C_2_H_5_OH, CH_3_OCH_3_, CH_3-COCH_3_, and CH_3_CHO. We classify cores with dense emission of CH_3_OH and at least one molecule from the other six molecules as hot core candidates. In addition to the existing sample of 60 strong hot cores from the ALMA-ATOMS survey, we have detected 40 new weak candidates through stacking. All hot core candidates display compact emission from at least one of the other six COM species. For the strong sample, the stacking method provides molecular column density estimates that are consistent with previous fitting results. For the newly identified weak candidates, all species except CH_3_CHO show compact emission in the stacked image, which cannot be fully resolved spatially. These weak candidates exhibit column densities of COMs that are approximately one order of magnitude lower than the ones of the strong sample. The entire hot core sample, including the weak candidates, reveals tight correlations between the compact emission of CH_3_OH and other COM species, suggesting they may share a similar chemical environment for COMs, with CH_3_OH potentially acting as a precursor for other COMs. Among the 100 hot cores in total, 43 exhibit extended CH_3_CHO emission spatially correlated with SiO and H^13^CO^+^, suggesting that CH_3_CHO may form in widely distributed shock regions. The molecular line stacking technique is used to identify hot core candidates in this work, leading to the identification of 40 new hot core candidates. Compared to spectral line fitting methods, it is faster and more convenient, and enables weaker hot cores to be detected with greater sensitivity.2025A&A...697A.190Lhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/697/A190CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/697/A190https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/697/A190http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/697/A190https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/697/A190https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/697/A190http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/697/A190GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/697/A190/tableb2 (Line parameters of CH_3_OH)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/697/A190/tableb2?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/697/A190/tableb2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/697/A190/tableb2?GETtext/xml+votable180.050000true128.0361667-43.22938330.0055555555555555566/28830 28913 28918 29092 29094 29096-29097 29101 29103 29113 29461 29509-29510 29529 30218 30241 30258-30259 30263 30269 30312 30318 30425 30616 30618 37850 37900 38019 39246 39251 41597 41653 41655 41677 41685 41688 41778 41804-41805 41814 41817 41820 42158-42159 42169 42171-42172 42207 42211 42214-42215 42224 42226 42229 42381 42390 42396 42398 42436 42445 42447 42451 42456 42497-42498 43010 43013 43021https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/697/A190?format=asciiMillimeterdefaultJ/A+A/697/A190/tableb1Identified transitions from stacked spectra of 100 hot coresrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSpeciesName of molecular speciesmeta.id;phys.molcharTransQuantum number of molecular transitionsphys.mol.qncharFreqRest frequency corresponding to the molecular transitionMHzem.freq;phys.atmol.transitiondoubleElowLower energy level temperature corresponding to the transitionKphysdoubleEupUpper energy level temperature corresponding to the transitionKphysdoubledatabase[CDMS JPL] A molecular spectral database for obtaining information on molecular transitionsmeta.id;meta.datasetcharJ/A+A/697/A190/tableb2Line parameters of CH_3_OHSimbadNameSimbad column added by the CDSmeta.idcharnullableID[1/100] Line number corresponding to each linespect.line.intensityintrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSourceName of sourcemeta.id;meta.maincharn_Source[N] N for hot core candidates newly identified in this workmeta.notecharRAJ2000Right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Declination (J2000)pos.eq.dec;meta.mainDistDistance from the source to the sunkpcpos.distancefloatthetaSource sizearcsecphys.angSizefloate_thetaError of source sizearcsecstat.error;pos.posAngfloatPAPosition angledegpos.posAnginte_PAError of position angledegstat.errorintIp(CH3OH)Peak intensity of the moment 0 map of CH_3OH emissionK.km/sspect.line.intensityfloate_Ip(CH3OH)Error value of the peak intensity of the moment 0 map of CH_3_OH emissionK.km/sstat.errorfloatI(CH3OH)Integrated intensity of the moment 0 map of CH_3_OH emissionK.km.s**-1.arcsec**-2spect.line.intensitydoublee_I(CH3OH)Error value of the integrated intensity of the moment 0 map of CH_3OH emissionK.km.s**-1.arcsec**-2stat.errorfloatN(CH3OH)Column density obtained by molecular fitting moment 0 map1e-16cm**-2phys.columnDensity;meta.modelledfloate_N(CH3OH)Error value of the column density obtained by molecular fitting moment 0 map1e-16cm**-2stat.errorfloatJ/A+A/697/A190/tableb3Physical parameters of CH_3_OCHO, C_2_H_5_CN and C_2_H_5_OHI(CH3OCHO)? Integrated intensity of the moment 0 map of CH_3_OCHO emissionK.km.s**-1.arcsec**-2spect.line.intensitydoublenullablerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintID[1/100] Line number corresponding to each linespect.line.intensityintSourceName of sourcemeta.id;meta.maincharn_Source[N] N for hot core candidates newly identified in this workmeta.notecharIp(CH3OCHO)? Peak intensity of the moment 0 map of CH_3_OCHO emissionK.km/sspect.line.intensityfloatnullablee_Ip(CH3OCHO)? Error value of the peak intensity of the moment 0 map of CH_3_OCHO emissionK.km/sstat.errorfloatnullablee_I(CH3OCHO)? Error value of the integrated intensity of the moment 0 map of CH_3OCHO emissionK.km.s**-1.arcsec**-2stat.errorfloatnullableN(CH3OCHO)? Column density obtained by molecular fitting moment 0 map1e-15cm**-2phys.columnDensity;meta.modelleddoublenullablee_N(CH3OCHO)? Error value of the column density obtained by molecular fitting moment 0 map1e-15cm**-2stat.errorfloatnullableIp(C2H5CN)? Peak intensity of the moment 0 map of C_2_H_5_CN emissionK.km/sspect.line.intensityfloatnullablee_Ip(C2H5CN)? Error value of the peak intensity of the moment 0 map of C_2_H_5_CN emissionK.km/sstat.errorfloatnullableI(C2H5CN)? Integrated intensity of the moment 0 map of C_2_H_5_CN emissionK.km.s**-1.arcsec**-2spect.line.intensitydoublenullablee_I(C2H5CN)? Error value of the integrated intensity of the moment 0 map of C_2_H_5_CN emissionK.km.s**-1.arcsec**-2stat.errorfloatnullableN(C2H5CN)? Column density obtained by molecular fitting moment 0 map1e-15cm**-2phys.columnDensity;meta.modelledfloatnullablee_N(C2H5CN)? Error value of the column density obtained by molecular fitting moment 0 map1e-15cm**-2stat.errorfloatnullableIp(C2H5OH)? Peak intensity of the moment 0 map of C_2_H_5_OH emissionK.km/sspect.line.intensityfloatnullablee_Ip(C2H5OH)? Error value of the peak intensity of the moment 0 map of C_2_H_5_OH emissionK.km/sstat.errorfloatnullableI(C2H5OH)? Integrated intensity of the moment 0 map of C_2_H_5_OH emissionK.km.s**-1.arcsec**-2spect.line.intensitydoublenullablee_I(C2H5OH)? Error value of the integrated intensity of the moment 0 map of C_2_H_5_OH emissionK.km.s**-1.arcsec**-2stat.errorfloatnullableN(C2H5OH)? Column density obtained by molecular fitting moment 0 map1e-15cm**-2phys.columnDensity;meta.modelledchare_N(C2H5OH)? Error value of the column density obtained by molecular fitting moment 0 map1e-15cm**-2stat.errorcharJ/A+A/697/A190/tableb4Physical parameters of CH_3_OCH_3_, CH_3_CHO and CH_3_COCH_3_recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintID[1/100] Line number corresponding to each linespect.line.intensityintSourceName of sourcemeta.id;meta.maincharn_Source[N] N for hot core candidates newly identified in this workmeta.notecharIp(CH3OCH3)? Peak intensity of the moment 0 map of CH_3_OCH_3_ emissionK.km/sspect.line.intensityfloatnullablee_Ip(CH3OCH3)? Error value of the peak intensity of the moment 0 map of CH_3_OCH_3_ emissionK.km/sstat.errorfloatnullableI(CH3OCH3)? Integrated intensity of the moment 0 map of CH_3_OCH_3_ emissionK.km.s**-1.arcsec**-2spect.line.intensitydoublenullablee_I(CH3OCH3)? Error value of the integrated intensity of the moment 0 map of CH_3_OCH_3_ emissionK.km.s**-1.arcsec**-2stat.errorfloatnullableN(CH3OCH3)? Column density obtained by molecular fitting moment 0 map1e-15cm**-2phys.columnDensity;meta.modelledfloatnullablee_N(CH3OCH3)? Error value of the column density obtained by molecular fitting moment 0 map1e-15cm**-2stat.errorfloatnullableIp(CH3CHO)? Peak intensity of the moment 0 map of CH_3_CHO emissionK.km/sspect.line.intensityfloatnullablee_Ip(CH3CHO)? Error value of the peak intensity of the moment 0 map of CH_3CHO emissionK.km/sstat.errorfloatnullableI(CH3CHO)? Integrated intensity of the moment 0 map of CH_3_CHO emissionK.km.s**-1.arcsec**-2spect.line.intensitydoublenullablee_I(CH3CHO)? Error value of the integrated intensity of the moment 0 map of CH_3_CHO emissionK.km.s**-1.arcsec**-2stat.errorfloatnullableN(CH3CHO)? Column density obtained by molecular fitting moment 0 map1e-15cm**-2phys.columnDensity;meta.modelledfloatnullablee_N(CH3CHO)? Error value of the column density obtained by molecular fitting moment 0 map1e-15cm**-2stat.errorfloatnullableIp(CH3COCH3)? Peak intensity of the moment 0 map of CH_3_COCH_3_ emissionK.km/sspect.line.intensityfloatnullablee_Ip(CH3COCH3)? Error value of the peak intensity of the moment 0 map of CH_3_COCH_3_ emissionK.km/sstat.errorfloatnullableI(CH3COCH3)? Integrated intensity of the moment 0 map of CH_3_COCH_3_ emissionK.km.s**-1.arcsec**-2spect.line.intensityfloatnullablee_I(CH3COCH3)? Error value of the integrated intensity of the moment 0 map of CH_3_COCH_3_ emissionK.km.s**-1.arcsec**-2stat.errorfloatnullableN(CH3COCH3)? Column density obtained by molecular fitting moment 0 map1e-15cm**-2phys.columnDensity;meta.modelledfloatnullablee_N(CH3COCH3)? Error value of the column density obtained by molecular fitting moment 0 map1e-15cm**-2stat.errorfloatnullable