J/MNRAS/500/4901ivo://CDS.VizieR/J/MNRAS/500/4901doi:10.26093/cds/vizier/bg-fm-4s5CDSDrozdovskaya M.N.Schroeder I I.R.H.G.Rubin M.Altwegg K.,van Dishoeck E.F.Kulterer B.M.De Keyser J.Fuselier S.A.Combi M.2026-08-03T07:30:43Z2023-11-14T08:04:17ZCDS support team

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

cds-question@unistra.frcometsmolecular-physicsinterstellar-mediumstar-forming-regionsDeuterated methanol is one of the most robust windows astrochemists have on the individual chemical reactions forming deuterium-bearing molecules and the physicochemical history of the regions where they reside. The first-time detection of mono- and di-deuterated methanol in a cometary coma is presented for comet 67P/Churyumov-Gerasimenko using Rosetta-ROSINA data. D-methanol (CH_3_OD and CH_2_DOH combined) and D_2_-methanol (CH_2_DOD and CHD_2_OH combined) have an abundance of 5.5+/0.46 and 0.00069+/-0.00014 per cent relative to normal methanol. The data span a methanol deuteration fraction (D/H ratio) in the 0.71-6.6 per cent range, accounting for statistical corrections for the location of D in the molecule and including statistical error propagation in the ROSINA measurements. It is argued that cometary CH_2_DOH forms from CO hydrogenation to CH_3_OH and subsequent H-D substitution reactions in CH_3_-R. CHD_2_OH is likely produced from deuterated formaldehyde. Meanwhile, CH_3_OD and CH_2_DOD could form via H-D exchange reactions in OH-R in the presence of deuterated water ice. Methanol formation and deuteration is argued to occur at the same epoch as D_2_O formation from HDO, with formation of mono-deuterated water, hydrogen sulphide, and ammonia occurring prior to that. The cometary D-methanol/methanol ratio is demonstrated to agree most closely with that in prestellar cores and low-mass protostellar regions. The results suggest that cometary methanol stems from the innate cold (10-20K) prestellar core that birthed our Solar system. Cometary volatiles individually reflect the evolutionary phases of star formation from cloud to core to protostar.2021MNRAS.500.4901Dhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/500/4901CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/500/4901https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/500/4901http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/500/4901https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/500/4901https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/500/4901http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/500/4901GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/500/4901/tabled1 (Carbon and oxygen isotopic ratios used in the literature for derivation of methanol column densities)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/500/4901/tabled1?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/500/4901/tabled1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/500/4901/tabled1?GETtext/xml+votable180.050000true85.9642083-1.04808330.005555555555555556Cone search capability for table J/MNRAS/500/4901/tabled2 (Column densities in cm^-2^ of CH_3_OH, CH_2_DOH, and CH_3_OD in star-forming regions and comets used to construct Figs 2-4 and B1-B3)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/500/4901/tabled2?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/500/4901/tabled2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/500/4901/tabled2?GETtext/xml+votable180.050000true76.069166725.180.0055555555555555566/859-860 862 1054 3068 14299 14307 14315 14317 14353 14622 14689 15430 15629 15759 15965 21439 22866 24300 24507 24554 27702 28830 28912 29103 29653 30241 30256 30318-30319 30366 30425 30595 31263 42456 42970https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/500/4901?format=asciidefaultJ/MNRAS/500/4901/tabled1Carbon and oxygen isotopic ratios used in the literature for derivation of methanol column densitiesSimbadNameSimbad column added by the CDSmeta.idcharnullablerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIsotopeCarbon or oxygen ratio (^12^C/^13^C or ^16^O/^18^O)meta.id;spect.linecharRatioIsotopic ratiophys.abundintNameSource namemeta.id;meta.maincharDist? Galactocentric distancepcpos.distanceintnullablee_Dist? Error on Distpcstat.errorfloatnullableRefReference for the source and the distancemeta.ref;pos.framechar_RARight Ascension (J2000) from SIMBAD (not part of the original data)degpos.eq.ra;meta.mainnullable_DEDeclination (J2000) from SIMBAD (not part of the original data)degpos.eq.dec;meta.mainnullableJ/MNRAS/500/4901/tabled2Column densities in cm^-2^ of CH_3_OH, CH_2_DOH, and CH_3_OD in star-forming regions and comets used to construct Figs 2-4 and B1-B3SimbadNameSimbad column added by the CDSmeta.idcharnullablerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameSource namemeta.id;meta.maincharPositionSource location (1)meta.notecharl_CH3OHLimit flag on CH3OHmeta.code.errorcharCH3OHColumn density of CH_3_OHcm**-2phys.columnDensitydoublel_CH2DOHLimit flag on CH2DOHmeta.code.errorcharCH2DOH? Column density of CH_2_DOHcm**-2phys.columnDensitydoublenullablel_CH3ODLimit flag on CH3ODmeta.code.errorcharCH3OD? Column density of CH_3_ODcm**-2phys.columnDensitydoublenullableRefReferencemeta.ref;pos.framecharCommentReason for exclusion (2)meta.notechar_RARight Ascension (J2000) from SIMBAD (not part of the original data)degpos.eq.ra;meta.mainnullable_DEDeclination (J2000) from SIMBAD (not part of the original data)degpos.eq.dec;meta.mainnullable