J/ApJ/783/36ivo://CDS.VizieR/J/ApJ/783/36doi:10.26093/cds/vizier.17830036CDSMcGuire B.A.Carroll P.B.Gratier P.Guzman V.Pety J.Roueff E.,Gerin M.Blake G.A.Remijan A.J.2017-01-23T22:00:00Z2016-04-13T14:51:37ZCDS support team

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

cds-question@unistra.frinterstellar-mediumatomic-physicsspectroscopyPety et al. have reported the detection of eight transitions of a closed-shell, linear molecule (B11244) in observations toward the Horsehead photodissociation region (PDR), which they attribute to the l-C_3_H^+^ cation. Recent high-level ab initio calculations have called this assignment into question; the anionic C_3_H^-^ molecule has been suggested as a more likely candidate. Here, we examine observations of the Horsehead PDR, Sgr B2(N), TMC-1, and IRC+10216 in the context of both l-C_3_H^+^ and C_3_H^-^. We find no observational evidence of K_a_=1 lines, which should be present were the carrier indeed C_3_H^-^. Additionally, we find a strong anticorrelation between the presence of known molecular anions and B11244 in these regions. Finally, we discuss the formation and destruction chemistry of C_3_H^-^ in the context of the physical conditions in the regions. Based on these results, we conclude there is little evidence to support the claim that the carrier is C_3_H^-^.2014ApJ...783...36Mhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/783/36CatalogResearchIsServedByTAP VizieR generic servicerelated-toJ/A+A/587/L4 : Methyl isocyanate in Orion (Cernicharo+, 2016)J/A+A/562/A56 : CH_2_CN^-^ and its deuterated derivatives (Majumdar+, 2014)J/ApJ/688/L83 : Detection of C_5_N^-^ in IRC +10216 (Cernicharo+, 2008)J/A+A/449/855 : Linelists for ammonia NH3, NH2D, ND2H, and ND3 (Coudert+, 2006)http://spec.jpl.nasa.gov/ : Jet Propulsion Laboratoryhttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/783/36https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/783/36http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/783/36https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/783/36https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/783/36http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/783/36GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapOpticaldefaultJ/ApJ/783/36/table2CALPGM catalog simulation of C_3_H^-^ formatrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintFreq[51/2e+06] Line frequency (1)MHzem.freqdoublee_Freq[0.005/1000] Error in FreqMHzstat.errordoublelogI[-11/-1] Log of integrated intensity at 300Klog(nm**2.MHz**-1)spect.line.intensitydoubleDOF[3] Degrees of freedom in rotational partition function (0=atoms, 2=linear molecule, 3=nonlinear molecule)stat.fit.dofintELow[0/3795] Lower state energy (2)cm**-1phys.energy;phys.atmol.leveldoubleGUp[3/41] Upper state degeneracyphys.electron.degenintSpecies[60006] Species tag or molecular identifier (60006) (3)meta.codeintQnF[303/303] Quantum number format identifier (4)phys.atmol.qnintQ1up[1/20] First quantum number upper state (5)phys.atmol.qnintQ2up[0/15] Second quantum number upper state (5)phys.atmol.qnintQ3up[0/20] Third quantum number upper state (5)phys.atmol.qnintQ4up? Fourth quantum number upper state (5)phys.atmol.qnintnullableQ5up? Fifth quantum number upper state (5)phys.atmol.qnintnullableQ6up? Sixth quantum number upper state (5)phys.atmol.qnintnullableQ1low[0/20] First quantum number lower state (5)phys.atmol.qnintQ2low[0/15] Second quantum number lower state (5)phys.atmol.qnintQ3low[0/20] Third quantum number lower state (5)phys.atmol.qnintQ4low? Fourth quantum number lower state (5)phys.atmol.qnintnullableQ5low? Fifth quantum number lower state (5)phys.atmol.qnintnullableQ6low? Sixth quantum number lower state (5)phys.atmol.qnintnullable