J/A+A/610/A44ivo://CDS.VizieR/J/A+A/610/A44doi:10.26093/cds/vizier.36100044CDSMargules L.Tercero B.Guillemin J.C.Motiyenko R.A.Cernicharo J.2018-03-15T09:10:34Z2018-02-26T09:10:16ZCDS support team

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

cds-question@unistra.fratomic-physicsAbout 40 cyanide molecules have been detected in the interstellar medium, but only 3 examples of organic isocyanide molecules were observed in this medium. Ethyl isocyanide is one of the best candidates for possible detection. To date, measurements of rotational spectra are limited to 40 GHz. The extrapolation of the prediction in the millimeter wave domain is inaccurate and does not permit an unambiguous detection. The rotational spectra were reinvestigated from 0.15 to 1THz. Using the new prediction, we searched for the compound ethyl isocyanide in Orion KL and Sgr B2. We newly assigned 2906 transitions and fitted these new data with those from previous studies, reaching quantum numbers up to J=103 and Ka=30. The asymmetric top Hamiltonian proposed by Watson in the Ir representation was used for the analysis, and both reductions A and S were tested. The search for CH_3_CH_2_NC in SgrB2 (IRAM 30m) and Orion KL (IRAM 30m, ALMA Science Verification) result in a non-detection; upper limits to the column density were derived.2018A&A...610A..44Mhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/610/A44CatalogResearchIsServedByTAP VizieR generic servicerelated-toJ/A+A/493/565 : Deuterated and ^15^N ethyl cyanides (Margules+, 2009)J/A+A/500/1109 : Rotational spectrum of HCOO^13^CH_3_ (Carvajal+, 2009)J/A+A/538/A51 : Rotational spectrum of CH_3_CH(NH_2_)CN (Mollendal+, 2012)J/A+A/538/A119 : Spectrum of ^18^O-methyl formate HCO^18^OCH_3_ (Tercero+ 2012)J/A+A/540/A51 : Submm spectrum of deuterated glycolaldehydes (Bouchez+, 2012)J/A+A/543/A46 : Submillimeter spectrum of HCOOCD_2_H (Coudert+, 2012)J/A+A/543/A135 : New analysis of ^13^C-CH_3_CH_2_CN up to 1THz (Richard+, 2012)J/A+A/544/A82 : Rotational spectroscopy of diisocyanomethane (Motiyenko+ 2012)J/A+A/548/A71 : Spectroscopy and ISM detection of formamide (Motiyenko+, 2012)J/A+A/549/A96 : mm and sub-mm spectra of 13C-glycolaldehydes (Haykal+, 2013)J/A+A/549/A128 : Singly deuterated isotopologues of formamide (Kutsenko+, 2013)J/A+A/552/A117 : Mono-deuterated dimethyl ether (Richard+, 2013)J/A+A/553/A84 : (Sub)mm spectrum of deuterated methyl cyanides (Nguyen+, 2013)J/A+A/559/A44 : Rotational spectrum of MAAN (CH_2_NCH_2_CN) (Motiyenko+, 2013)J/A+A/563/A137 : THz spectrum of methylamine (Motiyenko+, 2014)J/A+A/568/A58 : HCOO^13^CH_3_ rotational spectrum (Haykal+, 2014)J/A+A/579/A46 : Mono^13^C acetaldehydes mm/submm wave spectra (Margules+ 2015)J/A+A/591/A110 : ^15^NH_2_ amidogen radical rotational spectrumJ/A+A/601/A50 : Sub-millimeter spectra of 2-hydroxyacetonitrilehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/610/A44https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/610/A44http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/610/A44https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/610/A44https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/610/A44http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/610/A44GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapdefaultJ/A+A/610/A44/s1Measured frequencies and residuals from the fitrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintJ"Upper J quantum numberinstr.det.qe;stat.maxintKa"Upper Ka quantum numberphys.atmol.qn;stat.maxintKc"Upper Kc quantum numberphys.atmol.qn;stat.maxintJ'Lower J quantum numberinstr.det.qe;stat.minintKa'Lower Ka quantum numberphys.atmol.qn;stat.minintKc'Lower Kc quantum numberphys.atmol.qn;stat.minintFreqObserved transition frequencyem.freqdoubleO-CObserved - Calculated frequenciesstat.fit.residualdoubleuncUncertainty of measurementsstat.errordouble