English   español  
Please use this identifier to cite or link to this item: http://hdl.handle.net/10261/113178
Share/Impact:
Statistics
logo share SHARE   Add this article to your Mendeley library MendeleyBASE

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

Title

OH+in astrophysical media: State-to-state formation rates, einstein coefficients and inelastic collision rates with He

AuthorsGómez Carrasco, Susana ; Godard, Benjamin ; Lique, François; Bulut, Niyazi; Kł os, Jacek; Roncero, Octavio ; Aguado, Alfredo ; Aoiz, F. Javier ; Castillo, Jesús F.; Goicoechea, Javier R. ; Etxaluze, Mireya; Cernicharo, José
KeywordsAstrochemistry
ISM: molecules
Methods: laboratory: molecular
Molecular processes
Photon-dominated region (PDR)
Issue Date19-May-2014
PublisherAmerican Astronomical Society
CitationAstrophysical Journal 794 (2014)
Abstract© 2014 The American Astronomical Society. All rights reserved. The rate constants required to model the OH+observations in different regions of the interstellar medium have been determined using state of the art quantum methods. First, state-to-state rate constants for the H2(v = 0, J = 0, 1) + O+(4S) → H + OH+(X 3Σ-, v′, N) reaction have been obtained using a quantum wave packet method. The calculations have been compared with time-independent results to assess the accuracy of reaction probabilities at collision energies of about 1 meV. The good agreement between the simulations and the existing experimental cross sections in the 0.01-1 eV energy range shows the quality of the results. The calculated state-to-state rate constants have been fitted to an analytical form. Second, the Einstein coefficients of OH+have been obtained for all astronomically significant rovibrational bands involving the X 3Σ-and/or A 3Π electronic states. For this purpose, the potential energy curves and electric dipole transition moments for seven electronic states of OH+are calculated with ab initio methods at the highest level, including spin-orbit terms, and the rovibrational levels have been calculated including the empirical spin-rotation and spin-spin terms. Third, the state-to-state rate constants for inelastic collisions between He and OH+(X 3Σ-) have been calculated using a time-independent close coupling method on a new potential energy surface. All these rates have been implemented in detailed chemical and radiative transfer models. Applications of these models to various astronomical sources show that inelastic collisions dominate the excitation of the rotational levels of OH+. In the models considered, the excitation resulting from the chemical formation of OH+increases the line fluxes by about 10% or less depending on the density of the gas.
Description16 pags.; 11 figs.; 6 tabs.; 4 apps.
Publisher version (URL)http://dx.doi.org/10.1088/0004-637X/794/1/33
URIhttp://hdl.handle.net/10261/113178
DOI10.1088/0004-637X/794/1/33
Identifiersdoi: 10.1088/0004-637X/794/1/33
issn: 1538-4357
Appears in Collections:(CFMAC-IFF) Artículos
(ICMM) Artículos
Files in This Item:
File Description SizeFormat 
OH.pdf481,81 kBAdobe PDFThumbnail
View/Open
Show full item record
Review this work
 

Related articles:


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