Inverse temperature dependence of the dust submillimeter spectral index
Abstract
We present here a compilation of PRONAOS-based results concerning the temperature dependence of the dust submillimeter spectral index, including data from Galactic cirrus, star-forming regions and a circumstellar envelope. We observe large variations of the spectral index (from 0.8 to 2.4) in a wide range of temperatures (12 to 80 K). These spectral index variations follow a hyperbolic-shaped function of the temperature, large spectral indices (1.5-2.4) being observed in cold regions (12-20 K) while small indices (0.8-1.6) are observed in warm regions (35-80 K). Three interpretations are proposed: one is that the grain sizes change in warm and rather dense environments, another is that the chemical composition of the grains is not the same in different environments, a third one is that there is an intrinsic dependence of the dust spectral index on the temperature due to quantum processes.
Keywords
Cite
@article{arxiv.astro-ph/0310091,
title = {Inverse temperature dependence of the dust submillimeter spectral index},
author = {X. Dupac and J. -P. Bernard and N. Boudet and M. Giard and J. -M. Lamarre and C. Mény and F. Pajot and I. Ristorcelli},
journal= {arXiv preprint arXiv:astro-ph/0310091},
year = {2007}
}
Comments
2 pages, 1 figure, proc. of the SF2A conf. held in Bordeaux, France, June 2003, eds.: F. Combes, D. Barret and T. Contini, EdP-Sciences Conf. Series, p. 97