J/ApJS/282/18ivo://CDS.VizieR/J/ApJS/282/18CDSPineda J.E.Friesen R.K.Rosolowsky E.Chacon-Tanarro A.Chen M.C.-Y.,Di Francesco J.Kirk H.Punanova A.Seo Y.Shirley Y.Ginsburg A.,Offner S.S.R.Pandhi A.Singh A.Quan F.Arce H.G.Caselli P.,Choudhury S.Goodman A.A.Heitsch F.Martin P.G.Matzner C.D.,Myers P.C.Redaelli E.Scibelli S.co-PIsThe GAS collaboration2026-08-25T09:38:42Z2026-08-25T10:09:24ZCDS support team

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

cds-question@unistra.frmolecular-cloudsgalaxy-kinematicsinterstellar-mediummolecular-physicsradio-astronomyWe present an overview of the final data release (DR2) from the Green Bank Ammonia Survey (GAS). GAS is a large program at the Green Bank Telescope to map all Gould Belt star-forming regions with A_V_>~7mag visible from the Northern Hemisphere in emission from NH3 and other key molecular tracers. This final release includes the data for all the regions observed: Heiles Cloud 2 and B18 in Taurus; Barnard 1, Barnard 1-E, IC 348, NGC 1333, L1448, L1451, and Per7/34 in Perseus; L1688 and L1689 in Ophiuchus; Orion A (North and South) and Orion B in Orion; Cepheus; B59 in Pipe; Corona Australis East and West; IC 5146; and Serpens Aquila and MWC297 in Serpens. Similar to what was presented in GAS DR1, we find that the NH3 emission and dust continuum emission from Herschel correspond closely. We find that the NH3 emission is generally extended beyond the typical 0.1pc length scales of dense cores, and we find that the transition between coherent core and turbulent cloud is a common result. This shows that the regions of coherence are common throughout different star-forming regions, with a substantial fraction of the high column density regions displaying subsonic nonthermal velocity dispersions. We produce maps of the gas kinematics, temperature, and NH3 column densities through forward modeling of the hyperfine structure of the NH3 (1,1) and (2,2) lines. We show that the NH3 velocity dispersion, {sigma}v, and gas kinetic temperature, TK, vary systematically between the regions included in this release, with an increase in both the mean value and spread of {sigma}v and TK with increasing star formation activity.2026ApJS..282...18Phttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJS/282/18CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toVIII/64 : Westerhout's Catalogue of 82 Discrete Sources (Westerhout 1958)J/ApJS/125/161 : A database of dense cores mapped in ammonia (Jijina+, 1999)J/ApJ/526/788 : Survey of infall motions toward starless cores (Lee+, 1999)J/ApJS/153/523 : Starless cores in CS(3-2) and DCO^+^(2-1) lines (Lee+, 2004)J/A+A/487/993 : MAMBO Mapping of c2d Clouds and Cores (Kauffmann+, 2008)J/ApJS/175/509 : Ammonia spectral atlas in Perseus (Rosolowsky+, 2008)J/MNRAS/426/1972 : H_2_O Southern Gal. Plane Survey, HOPS. II (Purcell+, 2012)J/A+A/544/A146 : ATLASGAL cold high-mass clumps with NH_3_ (Wienen+, 2012)J/ApJ/779/113 : IR photometry of YSOs in the W40 region (Mallick+, 2013)J/ApJS/220/11 : SEDs of Spitzer YSOs in the Gould Belt (Dunham+, 2015)J/ApJ/830/127 : CLASSy: CARMA obs. in L1451 region of Perseus (Storm+, 2016)J/ApJ/846/144 : Virial analysis of the dense cores in Orion A (Kirk+, 2017)J/ApJ/867/151 : YSOs in the Gould Belt regions with Gaia-DR2 (Dzib+, 2018)J/ApJ/859/33 : GOBELINS. IV. VLBA obs. of Taurus (Galli+, 2018)J/A+A/619/A106 : 3D shape of Orion A from Gaia DR2 (Grossschedl+, 2018)J/A+A/610/A77 : Orion Integral Filament ALMA+IRAM30m N2H+ (Hacar+, 2018)J/AJ/156/84 : APOGEE-2 survey of Orion Complex. II. (Kounkel+, 2018)J/ApJ/865/73 : GOBELINS. V. Kinematics of Perseus (Ortiz-Leon+, 2018)J/A+A/658/A104 : HL Tau SO2 14(0-14)-13(1,13) datacube (Garufi+, 2022)J/A+A/667/A12 : PRODIGE I. Per-emb-50 datacubes (Valdivia-Mena+, 2022)J/A+A/677/A92 : Flow of gas in Barnard 5 (Valdivia-Mena+, 2023)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJS/282/18https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJS/282/18http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJS/282/18https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJS/282/18https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJS/282/18http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJS/282/18GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJS/282/18/table1 (Observed regions, distances, and masses)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJS/282/18/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJS/282/18/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJS/282/18/table1?GETtext/xml+votable180.050000true70.2525.86670.005555555555555556Cone search capability for table J/ApJS/282/18/table8 (NH3 core properties for selected regions)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJS/282/18/table8?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJS/282/18/table8?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJS/282/18/table8?GETtext/xml+votable180.050000true53.0687530.8255560.0055555555555555566/858-862 1052 1539 14029 16191 16196-16197 16203 21425 21428 21430 21436 21438-21439 22805 22854-22855 22873 29206 30251 30341 30343 30352 30366 42970 42981 42992 47828https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJS/282/18?format=asciiRadiodefaultJ/ApJS/282/18/table1Observed regions, distances, and massesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintCloudCloud namemeta.id;meta.maincharRegionMolecular cloud named substructure (as in Table 8)obs.fieldcharprimaryDist[126.6/813] Distancepcpos.distancefloatArea[0.01/0.39] Areadeg**2phys.angSizefloatSimbadNameSimbad column added by the CDSmeta.idcharnullableMass[8/3141] Total mass (1)solMassphys.massintRef[1/8]? Reference (2)meta.ref;pos.frameintnullableNcNumber of NH3 cores within this region (link to Table 8)meta.numberintnullable_RARight Ascension (J2000) from SIMBAD (not part of the original data)degpos.eq.ra;meta.main_DEDeclination (J2000) from SIMBAD (not part of the original data)degpos.eq.dec;meta.mainJ/ApJS/282/18/table8NH3 core properties for selected regionsRegionMolecular cloud named substructuremeta.id.parentcharalpha[0.16/9760]? Virial parameter of corephys.mass;arith.ratiodoublenullableCTypeCore classification as starless, prestellar, or protostellarsrc.classcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintGASID[0/253] Dendrogram index within Region (1)meta.id.part;meta.mainintRAJ2000[3/22] Hour of right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Degree of declination (J2000)pos.eq.dec;meta.mainvLSR[-8.2/12.4]? Mean local standard of rest velocity across corekm/sphys.veloc;pos.lsr;stat.meandoublenullablee_vLSR[0.009/3.2]? One-sigma uncertainty in vLSRkm/sstat.error;phys.veloc;pos.lsrdoublenullableSigma[0.1/3.2]? Mean velocity dispersion across corekm/sphys.veloc.dispersion;stat.meandoublenullablee_Sigma[0.005/3]? One-sigma uncertainty in Sigmakm/sstat.error;phys.veloc.dispersion;stat.meandoublenullableTex[2.86/10.64]? Mean excitation temperature derived from NH3 (1,1) and (2,2) fits across coreKphys.atmol.excitation;phys.temperaturedoublenullablee_Tex[0/2.31]? One-sigma uncertainty in TexKstat.error;phys.atmol.excitation;phys.temperaturedoublenullableTkin[7.85/46.2]? Mean kinetic temperature derived from NH3 (1,1) and (2,2) fits across coreKphys.temperature;stat.meandoublenullablee_Tkin[0/17.32]? One-sigma uncertainty in TkinKstat.error;phys.temperature;stat.meandoublenullablelogNNH3[13.57/14.97]? Mean of logarithm of NH3 column density across corecm**-2phys.columnDensitydoublenullablee_logNNH3[0/0.42]? One-sigma uncertainty in logNNH3cm**-2stat.error;phys.columnDensitydoublenullablesigth[0.16/0.41]? Thermal line width of H2 given mean kinetic temperature of corekm/sspect.line.widthdoublenullablesignth[0.07/3.2]? Mean non-thermal component of line width given mean kinetic temperature of corekm/sspect.line.width;stat.meandoublenullablecontIDID of cross-matched continuum counterpart of core (1)meta.id;spect.continuumcharcontr[0.006/0.16] Radius of core as derived using continuum datapcphys.size.radius;spect.continuumfloatcontM[0/166] Mass of core as derived using continuum datasolMassphys.massfloat