Sign on

SAO/NASA ADS Astronomy Abstract Service

· Find Similar Abstracts (with default settings below)
· Electronic Refereed Journal Article (HTML)
· Full Refereed Journal Article (PDF/Postscript)
· arXiv e-print (arXiv:1210.2391)
· References in the article
· Citations to the Article (22) (Citation History)
· Refereed Citations to the Article
· SIMBAD Objects (13)
· Also-Read Articles (Reads History)
· Translate This Page
Evidence for grain growth in molecular clouds: A Bayesian examination of the extinction law in Perseus
Foster, Jonathan B.; Mandel, Kaisey S.; Pineda, Jaime E.; Covey, Kevin R.; Arce, Héctor G.; Goodman, Alyssa A.
AA(Institute for Astrophysical Research, Boston University, Boston, MA 02215, USA; ), AB(Imperial College London, Blackett Laboratory, Prince Consort Road, London SW7 2AZ), AC(UK ALMA Regional Centre Node, Jodrell Bank Centre for Astrophysics, School of Physics and Astronomy, University of Manchester, Manchester M13 9PL), AD(Department of Astronomy, Cornell University, 226 Space Sciences Building, Ithaca, NY 14853, USA), AE(Department of Astronomy, Yale University, PO Box 208101, New Haven, CT 06520, USA), AF(Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA)
Monthly Notices of the Royal Astronomical Society, Volume 428, Issue 2, p.1606-1622 (MNRAS Homepage)
Publication Date:
Astronomy Keywords:
methods: statistical, ISM: clouds, dust, extinction
Abstract Copyright:
2012 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society
Bibliographic Code:


We investigate the shape of the extinction law in two 1° square fields of the Perseus molecular cloud complex. We combine deep red-optical (r, i and z band) observations obtained using Megacam on the MMT with UKIRT (United Kingdom Infrared Telescope) Infrared Deep Sky Survey near-infrared (J, H and K band) data to measure the colours of background stars. We develop a new hierarchical Bayesian statistical model, including measurement error, intrinsic colour variation, spectral type and dust reddening, to simultaneously infer parameters for individual stars and characteristics of the population. We implement an efficient Markov chain Monte Carlo algorithm utilizing generalized Gibbs sampling to compute coherent probabilistic inferences. We find a strong correlation between the extinction (AV) and the slope of the extinction law (parametrized by RV). Because the majority of the extinction towards our stars comes from the Perseus molecular cloud, we interpret this correlation as evidence of grain growth at moderate optical depths. The extinction law changes from the `diffuse' value of RV ˜ 3 to the `dense cloud' value of RV ˜ 5 as the column density rises from AV = 2 to 10 mag. This relationship is similar for the two regions in our study, despite their different physical conditions, suggesting that dust grain growth is a fairly universal process.
Bibtex entry for this abstract   Preferred format for this abstract (see Preferences)

Find Similar Abstracts:

Use: Authors
Keywords (in text query field)
Abstract Text
Return: Query Results Return    items starting with number
Query Form
Database: Astronomy
arXiv e-prints