J/ApJ/927/213ivo://CDS.VizieR/J/ApJ/927/213doi:10.26093/cds/vizier.19270213CDSPunanova A.Vasyunin A.Caselli P.Howard A.Spezzano S.Shirley Y.,Scibelli S.Harju J.2024-11-06T20:23:56Z2024-02-27T09:22:08ZCDS support team

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

cds-question@unistra.frstar-forming-regionsmillimeter-astronomysubmillimeter-astronomyinterstellar-mediumChemical models predict that in cold cores gas-phase methanol is expected to be abundant at the outer edge of the CO depletion zone, where CO is actively adsorbed. CO adsorption correlates with volume density in cold cores, and, in nearby molecular clouds, catastrophic CO freeze-out happens at volume densities above 10^4^cm^-3^. The methanol production rate is maximized there and its freeze-out rate does not overcome its production rate, while the molecules are shielded from UV destruction by gas and dust. Thus, in cold cores, methanol abundance should generally correlate with visual extinction, which depends on both volume and column density. In this work, we test the most basic model prediction that maximum methanol abundance is associated with a local A_V_~4mag in dense cores and constrain the model parameters with the observational data. With the IRAM 30m antenna, we mapped the CH_3_OH(2-1) and (3-2) transitions toward seven dense cores in the L1495 filament in Taurus to measure the methanol abundance. We use the Herschel/SPIRE maps to estimate visual extinction, and the C^18^O(2-1) maps from Tafalla & Hacar to estimate CO depletion. We explored the observed and modeled correlations between the methanol abundances, CO depletion, and visual extinction, varying the key model parameters. The modeling results show that hydrogen surface diffusion via tunneling is crucial to reproduce the observed methanol abundances, and the necessary reactive desorption efficiency matches the one deduced from laboratory experiments.2022ApJ...927..213Phttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/927/213CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toVII/220 : Barnard's Catalogue of 349 Dark Objects in the Sky (Barnard, 1927)VII/7 : Lynds' Catalogue of Dark Nebulae (LDN) (Lynds 1962)J/A+A/432/369 : Leiden Atomic & Molecular Database (LAMDA) (Schoeier+, 2005)J/ApJS/186/259 : Taurus Spitzer survey: new candidate members (Rebull+, 2010)J/A+A/554/A55 : C^18^O(1-0) and N_2_H^+^(1-0) in L1495/B213 (Hacar+, 2013)J/ApJ/786/29 : Catalog of distances to molecular clouds (Schlafly+, 2014)J/A+A/574/A104 : Dense cores in L1495/B213 complex (Tafalla+, 2015)J/MNRAS/463/1008 : LDN 1495 SCUBA-2 and Herschel data (Ward-Thompson+, 2016)J/A+A/604/A52 : B213 filament 150 and 260GHz emission maps (Bracco+, 2017)J/A+A/606/A142 : L1544 1.2 and 2mm emission maps (Chacon-Tanarro+, 2017)J/A+A/617/A27 : Kinematics of dense gas in L1495 filament (Punanova+, 2018)J/A+A/624/A108 : Modeling interstellar sulfur depletion (Laas+, 2019)J/A+A/630/A136 : Starless core L1521E chemical structure (Nagy+, 2019)J/A+A/638/A74 : Dense cores in Oph molecular cloud (Ladjelate+, 2020)J/A+A/633/A118 : 3mm-band study of L183 and L1544 (Lattanzi+, 2020)J/A+A/638/A85 : Taurus with Gaia & Herschel (Roccatagliata+, 2020)J/A+A/643/A60 : Starless cores CH_3_OH and c-C_3_H_2_ maps (Spezzano+, 2020)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/927/213https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/927/213http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/927/213https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/927/213https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/927/213http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/927/213GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/927/213/table1 (The mapped cores)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/927/213/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/927/213/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/927/213/table1?GETtext/xml+votable180.050000true64.4264458328.125244440.005555555555555556Associated datahttps://cdsarc.cds.unistra.fr/assocdata/?obs_collection=J/ApJ/927/2136/1080 1082 1168https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/927/213?format=asciiMillimeterdefaultJ/ApJ/927/213/table1The mapped coresCoreName of the dense core in Seo+ 2015ApJ...805..185S ; (<[SSG2015] NN> in Simbad)meta.id;meta.maincharRegRegion identifier according to Barnard 1927, VII/220 ; (<Barnard NNN> in Simbad)obs.fieldcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintf_ID[*] *: protostellar coremeta.codecharRAJ2000[4] Hour of right ascension (J2000) (1)pos.eq.ra;meta.mainDEJ2000[26/28] Degree of declination (J2000) (1)pos.eq.dec;meta.mainfits1Download the FITS file for the CH3OH(2-1) line at 96.74GHz (3mm)meta.ref.urlcharFileName1Name of the FITS file in subdirectory "fits" for the CH3OH(2-1) line at 96.74GHz (3mm)meta.id;meta.fitscharfits2Download the FITS file for the CH3OH(3-2) line at 145.10GHz (2mm)meta.ref.urlcharFileName2Name of the FITS file in subdirectory "fits" for the CH3OH(3-2) line at 145.10GHz (2mm)meta.id;meta.fitscharID[1/16]? Identifier of the dense core in Hacar+ 2013, J/A+A/554/A55 ; (<[HTK2013] NN> in Simbad)meta.idintnullable