J/MNRAS/499/6018ivo://CDS.VizieR/J/MNRAS/499/6018CDSZhu F.-Y.Wang J.-Z.Liu T.Kim K.-T.Zhu Q.-F.Li F.2023-11-08T07:57:29Z2023-11-08T08:56:19ZCDS support team

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

cds-question@unistra.frinterstellar-mediumprotostarsstar-forming-regionschemically-peculiar-starsradio-astronomyIn order to search for shocks in the very early stage of star formation, we performed single-point surveys of SiO J=1-0, 2-1, and 3-2 lines and the H_2_CO 2_12_-1_11_ line towards a sample of 100 high-mass starless clump candidates (SCCs) by using the Korean VLBI Network (KVN) 21-m radio telescopes. The detection rates of the SiO J=1-0, 2-1, 3-2 lines, and the H_2_CO line are 31.0, 31.0, 19.5, and 93.0 per cent, respectively. Shocks seem to be common in this stage of massive star formation. The widths of the observed SiO lines [full width at zero power (FWZP)] range from 3.4 to 55.1km/s. A significant fraction (~29 per cent) of the detected SiO spectra have broad line widths (FWZP>20km/s), which are very likely associated with fast shocks driven by protostellar outflows. This result suggests that about one third of the SiO-detected SCCs are not really starless but protostellar. On the other hand, about 40 per cent of the detected SiO spectra show narrow line widths (FWZP<10km/s) probably associated with low-velocity shocks which are not necessarily protostellar in origin. The estimated SiO column densities are mostly 0.31-4.32x10^12^cm^-2^. Comparing the SiO column densities derived from SiO J=1-0 and 2-1 lines, we suggest that the SiO molecules in the SCCs may be in the non-LTE condition. The SiO abundances to H_2_ are usually 0.20-10.92x10^-10^.2020MNRAS.499.6018Zhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/499/6018CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/ApJS/208/14 : BGPS. IX. Data release 2. (Ginsburg+, 2013)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/499/6018https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/499/6018http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/499/6018https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/499/6018https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/499/6018http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/499/6018GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/499/6018/table1 (The properties of the H_2_CO 2_12_-1_11_ line)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/499/6018/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/499/6018/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/499/6018/table1?GETtext/xml+votable180.050000true272.3911667-20.78354440.0055555555555555565/7564 6/29090-29091 29100-29101 29103 29112-29113 29115 29118 29505 29508 29510-29511 29522 29529 29532-29533 29535 30216 30218-30219 30222 30241 30244-30245 30260 30262https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/499/6018?format=asciiRadiodefaultJ/MNRAS/499/6018/table1The properties of the H_2_CO 2_12_-1_11_ linee_FWHM1? Error on FWHM1km/sstat.errorfloatnullablerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRAJ2000Right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Declination (J2000)pos.eq.dec;meta.mainVlsrNH31? NH_3_ line central velocity (1st component) (1)km/sspect.dopplerVelocfloatnullablee_VlsrNH31? Error on VlsrNH31km/sstat.errorfloatnullableVlsrNH32? NH_3_ line central velocity (2nd component) (1)km/sspect.dopplerVelocfloatnullablee_VlsrNH32? Error on VlsrNH32km/sstat.errorfloatnullableVlsrH2CO? H_2_CO line central velocitykm/sspect.dopplerVelocfloatnullablee_VlsrH2CO? Error on VlsrH2COkm/sstat.errorfloatnullableintTmbdv1? Velocity-integrated intensity (1st component)K.km/sspect.line.intensityfloatnullablee_intTmbdv1? Error on intTmbdv1K.km/sstat.errorfloatnullableintTmbdv2? Velocity-integrated intensity (2nd component)K.km/sspect.line.intensityfloatnullablee_intTmbdv2? Error on intTmbdv2K.km/sstat.errorfloatnullableTmb1? Line peak at main beam temperature (1st component)Kobs.paramfloatnullableTmb2? Line peak at main beam temperature (2nd component)Kobs.paramfloatnullableFWHM1? Full width at half-maximum (1st component)km/sspect.line.widthfloatnullableFWHM2? Full width at half-maximum (2nd component)km/sspect.line.widthfloatnullablee_FWHM2? Error on FWHM2km/sstat.errorfloatnullableLH2CO? H_2_CO luminosity1e-07solLumphys.luminositydoublenullableNH2CO? H_2_CO column densitycm**-2phys.columnDensitydoublenullableXH2CO? H_2_CO abundancephys.abunddoublenullableMoreLink to Tables 3, 4 and 5meta.ref.urlcharNameSource name (BGPS NNNN) from the BGPS v2.1 data (Ginsburg et al. 2013ApJS..208...14G, Cat. J/ApJS/208/14)meta.id;meta.maincharprimaryJ/MNRAS/499/6018/table3The properties of the SiO 1-0 and 2-1 lines emitted from corresponding sourcesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameSource name (BGPS NNNN) from the BGPS v2.1 data (Ginsburg et al. 2013ApJS..208...14G, Cat. J/ApJS/208/14)meta.id;meta.maincharVlsr1-0? SiO 1-0 line central velocitykm/sspect.dopplerVelocfloatnullablee_Vlsr1-0? Error on Vlsr1-0km/sstat.errorfloatnullableintTmbdv1-0? Velocity-integrated intensity for the SiO 1-0 lineK.km/sspect.line.intensityfloatnullablee_intTmbdv1-0? Error on intTmbdv1-0K.km/sstat.errorfloatnullableTmb1-0? Line peak at main beam temperature for the SiO 1-0 lineKobs.paramfloatnullableFWZP1-0? Full width at zero power for the SiO 1-0 linekm/sspect.line.eqWidthfloatnullableLSiO1-0? SiO 1-0 line luminosity1e-07solLumphys.luminosityfloatnullableVlsr2-1? SiO 2-1 line central velocitykm/sspect.dopplerVelocfloatnullablee_Vlsr2-1? Error on Vlsr2-1km/sstat.errorfloatnullableintTmbdv2-1? Velocity-integrated intensity for the SiO 2-1 lineK.km/sspect.line.intensityfloatnullablee_intTmbdv2-1? Error on intTmbdv2-1K.km/sstat.errorfloatnullableTmb2-1? Line peak at main beam temperature for the SiO 2-1 lineKobs.paramfloatnullableFWZP2-1? Full width at zero power for the SiO 2-1 linekm/sspect.line.eqWidthfloatnullableLSiO2-1? SiO 2-1 line luminosity1e-07solLumphys.luminosityfloatnullableJ/MNRAS/499/6018/table4The properties of the SiO 3-2 line emitted from corresponding sourcesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintVlsrSiO 3-2 line central velocitykm/sspect.dopplerVelocfloate_VlsrError on Vlsrkm/sstat.error;phys.veloc;pos.lsrfloatintTmbdvVelocity-integrated intensity for the SiO 3-2 lineK.km/sspect.line.intensityfloate_intTmbdvError on intTmbdvK.km/sstat.errorfloatTmbLine peak at main beam temperature for the SiO 3-2 lineKobs.paramfloatFWZPFull width at zero power for the SiO 3-2 linekm/sspect.line.eqWidthfloatLSiO3-2SiO 3-2 luminosity1e-07solLumphys.luminosityfloatNameSource name (BGPS NNNN) from the BGPS v2.1 data (Ginsburg et al. 2013ApJS..208...14G, Cat. J/ApJS/208/14)meta.id;meta.maincharJ/MNRAS/499/6018/table5The column densities and abundances of the SiO molecules estimated from the flux densities of the SiO 1-0, 2-1, and 3-2 lines and the excitation temperature is assumed to be 10KrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameSource name (BGPS NNNN) from the BGPS v2.1 data (Ginsburg et al. 2013ApJS..208...14G, Cat. J/ApJS/208/14)meta.id;meta.maincharMassClump masssolMassphys.massfloatNH2H_2_ column densitycm**-2phys.columnDensitydoubleNSiO1-0? SiO 1-0 column densitycm**-2phys.densitydoublenullableXSiO1-0? SiO 1-0 abundancephys.abunddoublenullableNSiO2-1? SiO 2-1 column densitycm**-2phys.densitydoublenullableXSiO2-1? SiO 2-1 abundancephys.abunddoublenullableNSiO3-2? SiO 3-2 column densitycm**-2phys.densitydoublenullableXSiO3-2? SiO 3-2 abundancephys.abunddoublenullable