J/AJ/132/1851ivo://CDS.VizieR/J/AJ/132/1851doi:10.26093/cds/vizier.51321851CDSAraya E.Hofner P.Olmi L.Kurtz S.Linz H.2008-11-11T08:37:16Z2008-11-11T09:31:06ZCDS support team

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

cds-question@unistra.frmolecular-cloudsspectroscopyastronomical-modelsWe report observations of the formaldehyde (H_2_CO) 6cm (4.8GHz) line toward L1551. The observations were conducted with the Arecibo Telescope (beam FWHP~1') to verify the tentative detection of H_2_CO thermal emission reported by Duncan and collaborators in 1987MNRAS.224..721D. The H_2_CO emission lines were expected to be present with a signal-to-noise ratio of >~10 in our spectra. However, we did not detect H_2_CO emission; i.e., our data rule out their tentative detection. The absence of H_2_CO emission is also confirmed by the fact that the H_2_CO line profiles at the two positions of expected emission are well fitted by a single absorption component (accounting for the hyperfine structure of the line) in one of the positions and by a single absorption line plus a red-wing absorption component in the second position. The Orion BN/KL region remains the only H_2_CO 6cm thermal emitter known. Our observations also demonstrate that the H_2_CO 6cm absorption line traces not only the quiescent molecular cloud but also the kinematics associated with the star formation process in L1551-IRS5.2006AJ....132.1851Ahttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/132/1851CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/A+A/318/879 : IR photometry of L1551/IRS5 (Men'shchikov+ 1997)J/A+A/420/945 : L1551 ISOCAM observations (Galfalk+, 2004)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/132/1851https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/132/1851http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/132/1851https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/132/1851https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/132/1851http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/132/1851GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/AJ/132/1851/table1 (Model Results)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/AJ/132/1851/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/AJ/132/1851/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/AJ/132/1851/table1?GETtext/xml+votable180.050000true67.823318.081670.0055555555555555566/23549https://cdsarc.cds.unistra.fr/viz-bin/moc/J/AJ/132/1851?format=asciiOpticaldefaultJ/AJ/132/1851/table1Model ResultsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintoRAOffset along Right Ascension (1)arcminpos.eq.ra;arith.diffintoDEOffset along Declination (1)arcminpos.eq.dec;arith.diffintTex0Excitation temperature lower limitKphys.atmol.excitation;stat.minfloatTex1Excitation temperature upper limitKphys.atmol.excitation;stat.maxfloattau0Optical depth lower limitphys.absorption.opticalDepthfloattau1Optical depth upper limitphys.absorption.opticalDepthfloatDelV0Line width lower limitkm/sspect.line.width;stat.minfloatDelV1Line width upper limitkm/sspect.line.width;stat.maxfloatVLSR0The F=2-2 hyperfine component LSR velocity, lower limitkm/sphys.veloc;pos.lsrfloatVLSR1The F=2-2 hyperfine component LSR velocity, upper limitkm/sphys.veloc;pos.lsrfloatchi2{chi}^2^ value (2)stat.fit.chi2floatDchi2? Different {chi}^2^ value for DelV and VLSR ranges (3)stat.fit.chi2floatnullableWing[c] Presence of wings (4)meta.codechar_RAComputed Right Ascension for Equinox: J2000degpos.eq.ra;meta.main_DEComputed Declination for Equinox: J2000degpos.eq.dec;meta.main