The system will be going down for regular maintenance. Please save your work and logout.

Show simple item record

Chemistry in disks. I. Deep search for N2H+ in the protoplanetary disks around LkCa 15, MWC 480, and DM Tauri

hal.structure.identifierAMOR 2007
dc.contributor.authorDUTREY, Anne
dc.contributor.authorHENNING, T.
hal.structure.identifierAMOR 2007
dc.contributor.authorGUILLOTEAU, S.
dc.contributor.authorSEMENOV, D.
hal.structure.identifierInstitut de RadioAstronomie Millimétrique [IRAM]
dc.contributor.authorPIÉTU, V.
dc.contributor.authorSCHREYER, K.
hal.structure.identifierAMOR 2007
dc.contributor.authorBACMANN, A.
dc.contributor.authorLAUNHARDT, R.
hal.structure.identifierInstitut de RadioAstronomie Millimétrique [IRAM]
hal.structure.identifierLaboratoire d'Etude du Rayonnement et de la Matière en Astrophysique [LERMA]
dc.contributor.authorPETY, J.
hal.structure.identifierInstitut de RadioAstronomie Millimétrique [IRAM]
dc.contributor.authorGUETH, F.
dc.date.issued2007-03
dc.identifier.issn0004-6361
dc.description.abstractEnAims.To constrain the ionization fraction in protoplanetary disks, we present new high-sensitivity interferometric observations of N2H+ in three disks surrounding DM Tau, LkCa 15, and MWC 480. Methods: We used the IRAM PdBI array to observe the N2H+ J=1-0 line and applied a ?^2-minimization technique to estimate corresponding column densities. These values are compared, together with HCO+ column densities, to results of a steady-state disk model with a vertical temperature gradient coupled to gas-grain chemistry. Results: We report two N2H+ detections for LkCa 15 and DM Tau at the 5 ? level and an upper limit for MWC 480. The column density derived from the data for LkCa 15 is much lower than previously reported. The [ N2H^+/HCO^+] ratio is on the order of 0.02-0.03. So far, HCO+ remains the most abundant observed molecular ion in disks. Conclusions: .All the observed values generally agree with the modelled column densities of disks at an evolutionary stage of a few million years (within the uncertainty limits), but the radial distribution of the molecules is not reproduced well. The low inferred concentration of N2H+ in three disks around low-mass and intermediate-mass young stars implies that this ion is not a sensitive tracer of the overall disk ionization fraction. Based on observations carried out with the IRAM Plateau de Bure Interferometer. IRAM is supported by INSU/CNRS (France), MPG (Germany) and IGN (Spain). Research partially supported by PCMI, the French national program for the Physics and Chemistry of the Interstellar Medium.
dc.language.isoen
dc.publisherEDP Sciences
dc.subject.enstars: pre-main sequence
dc.subject.enplanetary systems: protoplanetary disks
dc.subject.ensubmillimeter
dc.title.enChemistry in disks. I. Deep search for N2H+ in the protoplanetary disks around LkCa 15, MWC 480, and DM Tauri
dc.typeArticle de revue
dc.identifier.doi10.1051/0004-6361:20065385
dc.subject.halPhysique [physics]/Astrophysique [astro-ph]/Cosmologie et astrophysique extra-galactique [astro-ph.CO]
dc.subject.halPlanète et Univers [physics]/Astrophysique [astro-ph]
dc.identifier.arxivastro-ph/0612534
bordeaux.journalAstronomy and Astrophysics - A&A
bordeaux.page615-623
bordeaux.volume464
bordeaux.peerReviewedoui
hal.identifierhal-00315760
hal.version1
hal.popularnon
hal.audienceNon spécifiée
hal.origin.linkhttps://hal.archives-ouvertes.fr//hal-00315760v1
bordeaux.COinSctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:journal&rft.jtitle=Astronomy%20and%20Astrophysics%20-%20A&A&rft.date=2007-03&rft.volume=464&rft.spage=615-623&rft.epage=615-623&rft.eissn=0004-6361&rft.issn=0004-6361&rft.au=DUTREY,%20Anne&HENNING,%20T.&GUILLOTEAU,%20S.&SEMENOV,%20D.&PI%C3%89TU,%20V.&rft.genre=article


Files in this item

FilesSizeFormatView

There are no files associated with this item.

This item appears in the following Collection(s)

Show simple item record