K. Foyle, C. D. Wilson, E. Mentuch, G. Bendo, A. Dariush, T. Parkin, M. Pohlen, M. Sauvage, M. W. L. Smith, H. Roussel, M. Baes, M. Boquien, A. Boselli, D. L. Clements, A. Cooray, J. I. Davies, S. A. Eales, S. Madden, M. J. Page, Spinoglio
We examine the dust and gas properties of the nearby, barred galaxy M83,
which is part of the Very Nearby Galaxy Survey. Using images from the PACS and
SPIRE instruments of Herschel, we examine the dust temperature and dust mass
surface density distribution. We find that the nuclear, bar and spiral arm
regions exhibit higher dust temperatures and masses compared to interarm
regions. However, the distribution of dust temperature and mass are not
spatially coincident. Assuming a trailing spiral structure, the dust
temperature peaks in the spiral arms lie ahead of the dust surface density
peaks. The dust mass surface density correlates well with the distribution of
molecular gas as traced by CO (J=3-2) images (JCMT) and the star formation rate
as traced by H?2 with a correction for obscured star formation using 24 micron
emission. Using HI images from THINGS to trace the atomic gas component, we
make total gas mass surface density maps and calculate the gas-to-dust ratio.
We find a mean gas-to-dust ratio of 84 \pm 4 with higher values in the inner
region assuming a constant CO-to-H2 conversion factor. We also examine the
gas-to-dust ratio using CO-to-H2 conversion factor that varies with
metallicity.
View original:
http://arxiv.org/abs/1201.2178
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