English   español  
Please use this identifier to cite or link to this item: http://hdl.handle.net/10261/182889
logo share SHARE logo core CORE   Add this article to your Mendeley library MendeleyBASE

Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL | DATACITE
Exportar a otros formatos:


Chemical composition of the circumstellar disk around AB Aurigae

AuthorsPacheco-Vázquez, S.; Fuente, A.; Agúndez, Marcelino ; Pinte, C.; Alonso-Albi, T.; Neri, R.; Cernicharo, José ; Goicoechea, Javier R. ; Berné, O.; Wiesenfeld, L.; Bachiller, R.; Lefloch, Bertrand
KeywordsStars: individual: AB Aurigae
Circumstellar matter
Protoplanetary disks
Stars: variables: T Tauri, Herbig Ae/Be
Stars: formation
Stars: pre-main sequence
Issue Date10-Jun-2015
PublisherEDP Sciences
CitationAstronomy and Astrophysics 578: A81 (2015)
Abstract[Aims] Our goal is to determine the molecular composition of the circumstellar disk around AB Aurigae (hereafter, AB Aur). AB Aur is a prototypical Herbig Ae star and the understanding of its disk chemistry is paramount for understanding the chemical evolution of the gas in warm disks.
[Methods] We used the IRAM 30-m telescope to perform a sensitive search for molecular lines in AB Aur as part of the IRAM Large program ASAI (a chemical survey of Sun-like star-forming regions). These data were complemented with interferometric observations of the HCO+ 1→0 and C17O 1→0 lines using the IRAM Plateau de Bure Interferometer (PdBI). Single-dish and interferometric data were used to constrain chemical models.
[Results] Throughout the survey, several lines of CO and its isotopologues, HCO+, H2CO, HCN, CN, and CS, were detected. In addition, we detected the SO 54→33 and 56→45 lines, confirming the previously tentative detection. Compared to other T Tauri and Herbig Ae disks, AB Aur presents low HCN 3→2/HCO+ 3→2 and CN 2→1/HCN 3→2 line intensity ratios, similar to other transition disks. AB Aur is the only protoplanetary disk detected in SO thus far, and its detection is consistent with interpretation of this disk being younger than those associated with T Tauri stars.
[Conclusions] We modeled the line profiles using a chemical model and a radiative transfer 3D code. Our model assumes a flared disk in hydrostatic equilibrium. The best agreement with observations was obtained for a disk with a mass of 0.01 M⊙, Rin = 110 AU, Rout = 550 AU, a surface density radial index of 1.5, and an inclination of 27◦. The intensities and line profiles were reproduced within a factor of ∼2 for most lines. This agreement is reasonable considering the simplicity of our model that neglects any structure within the disk. However, the HCN 3→2 and CN 2→1 line intensities were predicted to be more intense by a factor of >10. We discuss several scenarios to explain this discrepancy.
Publisher version (URL)https://doi.org/10.1051/0004-6361/201425347
Identifiersdoi: 10.1051/0004-6361/201425347
e-issn: 1432-0746
issn: 0004-6361
Appears in Collections:(ICMM) Artículos
Files in This Item:
File Description SizeFormat 
accesoRestringido.pdf15,38 kBAdobe PDFThumbnail
Show full item record
Review this work

WARNING: Items in Digital.CSIC are protected by copyright, with all rights reserved, unless otherwise indicated.