J/A+A/651/A86ivo://CDS.VizieR/J/A+A/651/A86doi:10.26093/cds/vizier.36510086CDSDokara R.Brunthaler A.Menten K.M.Dzib S.A.Reich W.Cotton W.D.,Anderson L.D.Chen C.-H.R.Gong Y.Medina S.-N.X.Ortiz-Leon G.N.,Rugel M.Urquhart J.S.Wyrowski F.Yang A.Y.Beuther H.,Billington S.J.Csengeri T.Carrasco-Gonzalez C.Roy N.2023-02-08T11:42:44Z2021-07-22T09:00:59ZCDS support team

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

cds-question@unistra.frsurveysgalaxy-planesmilky-way-galaxysupernova-remnantsradio-sourcespolarimetryThe properties of the population of Galactic supernova remnants (SNRs) are essential to our understanding of the dynamics of the interstellar medium (ISM) in the Milky Way. However, the completeness of the catalog of Galactic SNRs is expected to be only ~30%, with on order 700 SNRs yet to be detected. Deep interferometric radio continuum surveys of the Galactic plane help in rectifying this apparent deficiency by identifying low surface brightness SNRs and compact SNRs that have not been detected in previous surveys. However, SNRs are routinely confused with HII regions, which can have similar radio morphologies. Radio spectral index, polarization, and emission at mid-infrared (MIR) wavelengths can help distinguish between SNRs and HII regions. We aim to identify SNR candidates using continuum images from the Karl G. Jansky Very Large Array GLObal view of the STAR formation in the Milky Way (GLOSTAR) survey. GLOSTAR is a C-band (4-8GHz) radio wavelength survey of the Galactic plane covering 358{deg}>=l<=60{deg}, |b|<=1{deg}. The continuum images from this survey, which resulted from observations with the most compact configuration of the array, have an angular resolution of 18''. We searched for SNRs in these images to identify known SNRs, previously identified SNR candidates, and new SNR candidates. We study these objects in MIR surveys and the GLOSTAR polarization data to classify their emission as thermal or nonthermal. We identify 157 SNR candidates, of which 80 are new. Polarization measurements provide evidence of nonthermal emission from 9 of these candidates. We find that two previously identified candidates are filaments. We also detect emission from 91 of the 94 known SNRs in the survey region. Four of these are reclassified as HII regions following detection in MIR surveys. The better sensitivity and resolution of the GLOSTAR data have led to the identification of 157 SNR candidates, along with the reclassification of several misidentified objects. We show that the polarization measurements can identify nonthermal emission, despite the diffuse Galactic synchrotron emission. These results underscore the importance of higher resolution and higher sensitivity radio continuum data in identifying and confirming SNRs.2021A&A...651A..86Dhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/651/A86CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toVII/284 : A Catalogue of Galactic Supernova Remnants (Green, 2019)J/A+A/627/A175 : GLOSTAR. Radio Source Catalogue I (Medina+ 2019)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/651/A86https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/651/A86http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/651/A86https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/651/A86https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/651/A86http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/651/A86GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/651/A86/table2 (*Green (2019, Cat. VII/284) SNRs identified in the GLOSTAR-VLA images)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/651/A86/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/651/A86/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/651/A86/table2?GETtext/xml+votable180.050000true266.405-28.936170.005555555555555556Cone search capability for table J/A+A/651/A86/table3 (*Newly identified SNR candidates in the GLOSTAR-VLA data)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/651/A86/table3?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/651/A86/table3?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/651/A86/table3?GETtext/xml+votable180.050000true267.64391-27.319080.005555555555555556Cone search capability for table J/A+A/651/A86/table4 (*Previously identified SNR candidates with counterparts in the GLOSTAR-VLA data)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/651/A86/table4?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/651/A86/table4?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/651/A86/table4?GETtext/xml+votable180.050000true268.78346-26.582230.0055555555555555565/7206 7228 7377 7561 7605 7679 6/12970 12974 14340 14342 14352-14353 14355 28830-28831 28837 28848 28874-28875 28878-28879 28890 28896-28897 28900-28901 28918-28919 28925 29090 29094 29096-29097 29100-29101 29103 29112 29114-29115 29118-29119 29162 29166 29460-29461 29504-29505 29507 29516 29522-29523 29528-29529 29532-29533 29535 30216 30219 30240-30241 30256 30258-30259 30262-30263 30268-30269 30306 30312-30313 30315 30317-30319 30330-30331 30417 30419 30429 30594-30595 30598 30604-30605 30607 30616 30619 30622 30645 30667 30690 30692 30694 30710 307123.8431204771608934e-24 3.8431204771608934e-24https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/651/A86?format=asciiRadiodefaultJ/A+A/651/A86/table2*Green (2019, Cat. VII/284) SNRs identified in the GLOSTAR-VLA imagesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameName of the sourcemeta.id;meta.maincharGLON[0.0/359.12] Galactic longitudedegpos.galactic.lonGLAT[-1.11/1.0] Galactic latitudedegpos.galactic.latRadius[1.3/36.5] Radius of the circle encompassing all emission of the sourcearcminphys.angSizefloatTypeType of the source (G1)meta.code.classcharSint[0.0/5.78]? 5.8GHz integrated flux densityJyphot.flux.density;em.radio.3-6GHzdoublenullablee_Sint[0.0/0.04]? Error in the 5.8GHz integrated flux densityJystat.errordoublenullableLint[0.0/0.63]? 5.8GHz integrated linearly polarized flux densityJyphot.flux.density;em.radio.3-6GHzdoublenullablee_Lint[0.0/0.11]? Error in the 5.8GHz integrated linearly polarized flux densityJystat.errorfloatnullableSimbadNameSimbad column added by the CDSmeta.idcharnullable_RA.icrsRight ascension (ICRS) (computed by VizieR, not part of the original data. The format may include more digits than the original data because of internal accuracy requirements in VizieR and across other CDS services)degpos.eq.ranullableindexed_DE.icrsDeclination (ICRS) (computed by VizieR, not part of the original data. The format may include more digits than the original data because of internal accuracy requirements in VizieR and across other CDS services)degpos.eq.decnullableindexedp[0.0/0.43]? Degree of linear polarizationphys.polarization.lineardoublenullablee_p[0.0/0.11]? Error in the degree of linear polarizationstat.errordoublenullablel_p[Y] Linear polarization upper limit flag. =Y if it is an upper limit.meta.code.errorcharRemarksSome remarks on the sourcemeta.notecharJ/A+A/651/A86/table3*Newly identified SNR candidates in the GLOSTAR-VLA dataSimbadNameSimbad column added by the CDSmeta.idcharnullable_RA.icrsRight ascension (ICRS) (computed by VizieR, not part of the original data. The format may include more digits than the original data because of internal accuracy requirements in VizieR and across other CDS services)degpos.eq.ranullableindexed_DE.icrsDeclination (ICRS) (computed by VizieR, not part of the original data. The format may include more digits than the original data because of internal accuracy requirements in VizieR and across other CDS services)degpos.eq.decnullableindexedrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameName of the sourcemeta.id;meta.maincharGLON[1.94/359.18] Galactic longitudedegpos.galactic.lonGLAT[-0.98/0.82] Galactic latitudedegpos.galactic.latRadius[1.0/27.0] Radius of the circle encompassing all emission of the sourcearcminphys.angSizefloatTypeType of the source (G1)meta.code.classcharSint[0.0/0.23]? 5.8GHz integrated flux densityJyphot.flux.density;em.radio.3-6GHzdoublenullablee_Sint[0.0/0.02]? Error in the 5.8GHz integrated flux densityJystat.errordoublenullableLint[0.0/0.02]? 5.8GHz integrated linearly polarized flux densityJyphot.flux.density;em.radio.3-6GHzdoublenullablee_Lint[0.0/0.01]? Error in the 5.8GHz integrated linearly polarized flux densityJystat.errorfloatnullablep[0.0/0.48]? Degree of linear polarizationphys.polarization.lineardoublenullablee_p[0.0/0.21]? Error in the degree of linear polarizationstat.errordoublenullablel_p[Y] Linear polarization upper limit flag (=Y if it is an upper limit)meta.code.errorcharDet-inPrevious surveys in which the source can be identified (2)meta.notecharJ/A+A/651/A86/table4*Previously identified SNR candidates with counterparts in the GLOSTAR-VLA dataSimbadNameSimbad column added by the CDSmeta.idcharnullableRemarksSome remarks on the sourcemeta.notecharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameName of the sourcemeta.id;meta.maincharGLON[3.1/359.56] Galactic longitudedegpos.galactic.lon_RA.icrsRight ascension (ICRS) (computed by VizieR, not part of the original data. The format may include more digits than the original data because of internal accuracy requirements in VizieR and across other CDS services)degpos.eq.ranullableindexed_DE.icrsDeclination (ICRS) (computed by VizieR, not part of the original data. The format may include more digits than the original data because of internal accuracy requirements in VizieR and across other CDS services)degpos.eq.decnullableindexedGLAT[-0.86/0.9] Galactic latitudedegpos.galactic.latRadius[0.6/20.0] Radius of the circle encompassing all emission of the sourcearcminphys.angSizefloatTypeType of the source (G1)meta.code.classcharSint[0.0/1.06]? 5.8GHz integrated flux densityJyphot.flux.density;em.radio.3-6GHzdoublenullablee_Sint[0.0/0.02]? Error in the 5.8GHz integrated flux densityJystat.errordoublenullableLint[0.0/0.09]? 5.8GHz integrated linearly polarized flux densityJyphot.flux.density;em.radio.3-6GHzdoublenullablee_Lint[0.0/0.02]? Error in the 5.8GHz integrated linearly polarized flux densityJystat.errorfloatnullablep[0.0/0.71]? Degree of linear polarizationphys.polarization.lineardoublenullablee_p[0.0/0.4]? Error in the degree of linear polarizationstat.errordoublenullablel_p[Y] Linear polarization upper limit flag (=Y if it is an upper limit)meta.code.errorcharRefsPrevious studies on this object (2)meta.bibchar