English   español  
Please use this identifier to cite or link to this item: http://hdl.handle.net/10261/10837
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:


Understanding the 8 μm versus Paα Relationship on Subarcsecond Scales in Luminous Infrared Galaxies

AuthorsDíaz-Santos, T. ; Alonso-Herrero, A. ; Colina, Luis ; Packham, Christopher; Radomski, James T.; Telesco, Charles M.
KeywordsGalaxies: Nuclei
Galaxies: Star Clusters
Galaxies: Starburst
Infrared: Galaxies
Issue Date20-Sep-2008
PublisherAmerican Astronomical Society
Institute of Physics Publishing
CitationThe Astrophysical Journal (ApJ) 685(1): 211-224 (2008)
AbstractThis work explores in detail the relation between the 8 μm and the Paα emissions for 122 H II regions identified in a sample of 10 low-z LIRGs with nearly constant metallicity [12+log(O/H)~8.8]. We use Gemini T-ReCS high spatial resolution (<~0.4"~120 pc for the average distance of 60 Mpc of our sample) mid-infrared imaging (at 8.7 or 10.3 μm), together with HST NICMOS continuum and Paα images. The LIRG H II regions extend the L8μm vs. LPaα relation found for H II knots in the high-metallicity SINGS galaxies by about 2 orders of magnitude to higher luminosities. Since the metallicity of the LIRG sample is nearly constant, we can rule out this effect as a cause for the scatter seen in the relationship. In turn, it is attributed to two effects: age and PAH features. The L8μm/LPaα ratio, which varies by a factor of 10 for the LIRG H II regions, is reproduced by a model with instantaneous star formation and ages ranging from ~4 to 7.5 Myr. The remaining dispersion around the model predictions for a given age is probably due to differential contributions of the PAH features (the 8.6 μm, in our case) to the 8 μm emission from galaxy to galaxy.
Description14 pages, 9 figures, 4 tables.-- Based on observations obtained with T-ReCS instrument at the Gemini South Observatory, which is operated by the Association of Universities for Research in Astronomy (AURA), Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: NSF (United States), PPARC (UK), NRC (Canada), CONICYT (Chile) ARC (Australia), CNPq (Brazil), and CONICET (Argentina).-- Also based on observations with the NASA/ESA Hubble Space Telescope, obtained from the data archive at the Space Telescope Science Institute, which is operated by AURA, Inc., under NASA contract NAS 5-266555.
Publisher version (URL)http://dx.doi.org/10.1086/588276
Appears in Collections:(CFMAC-IEM) Artículos
Files in This Item:
File Description SizeFormat 
TReCSimaging_LIRGs_paper2.pdf2,31 MBAdobe PDFThumbnail
Show full item record
Review this work

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