J/A+A/541/A121ivo://CDS.VizieR/J/A+A/541/A121doi:10.26093/cds/vizier.35410121CDSOrdu M.H.Mueller H.S.P.Walters A.Nunez M.Lewen F.Belloche A.,Menten K.M.Schlemmer S.2017-12-15T10:54:59Z2012-05-11T07:39:19ZCDS support team

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

cds-question@unistra.fratomic-physicsThe saturated n-propyl cyanide has recently been detected in Sagittarius B2(N). The next larger unbranched alkyl cyanide is n-butyl cyanide. We want to provide accurate rest frequency predictions beyond the millimeter wave range to search for this molecule in the Galactic center source Sagittarius B2(N) and facilitate its detection in space. The laboratory rotational spectrum of n-butyl cyanide has been investigated between 75 and 348GHz. We have searched for emission lines caused by the molecule in our sensitive IRAM 30m molecular line survey of Sagittarius B2(N). More than one thousand rotational transitions have been identified in the laboratory for each of the three conformers for which limited data had been obtained previously in a molecular beam microwave study. The quantum number range has been greatly extended to J~120 or more and Ka>35, resulting in accurate spectroscopic parameters and accurate rest frequency calculations up to about 500GHz for strong to moderately weak transitions of the two lower energy conformers. Upper limits of the column densities of N<=3x10^15^cm^-2^ and 8x10^15^cm^-2^ were derived towards Sagittarius B2(N) for the two lower energy conformers, anti-anti and gauche-anti, respectively. The present data will be helpful to identify n-butyl cyanide at millimeter or longer wavelengths with radio telescope arrays such as ALMA, NOEMA, or EVLA. In particular, its detection in Sagittarius B2(N) with ALMA seems feasible.2012A&A...541A.121Ohttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/541/A121CatalogResearchIsServedByTAP VizieR generic servicerelated-toJ/A+A/466/255 : Isotopic ethyl cyanide (Demyk+, 2007)J/A+A/493/565 : Deuterated and ^15^N ethyl cyanides (Margules+, 2009)J/ApJS/184/133 : New ground-state measurements of ethyl cyanide (Brauer+, 2009)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/541/A121https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/541/A121http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/541/A121https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/541/A121https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/541/A121http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/541/A121GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapdefaultJ/A+A/541/A121/C4H9CNMeasured lines of the 3 conformers of the n-butyl cyanide C_4_H_9_CN: anti-anti (AA, table3), gauche-anti (GA, table4) and anti-gauche (AG, table5)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintConfSimbad column added by the CDSphys.atmol.configurationcharJ"[1/136] Upper J quantum numberinstr.det.qe;stat.maxintKa"[0/47] Upper Ka quantum numberphys.atmol.qn;stat.maxintKc"[0/136] Upper Kc quantum numberphys.atmol.qn;stat.maxintF"[0/9]? Upper F quantum numberphys.atmol.qnintnullableJ'[0/135] Lower J quantum numberinstr.det.qe;stat.minintKa'[0/47] Lower Ka quantum numberphys.atmol.qn;stat.minintKc'[0/136] Lower Kc quantum numberphys.atmol.qn;stat.minintF'[0/9]? Lower F quantum numberphys.atmol.qnintnullableFreq[4000/350000] Observed transition frequencyMHzem.freq;phys.atmol.transitiondoublee_FreqUncertainty of measurementsMHzstat.errorfloatO-CObserved - Calculated frequenciesMHzem.freqdoubleWeight[0/1]? Weight for blended linesstat.weight;phys.atmol.weightfloatnullable