D. A. Dale, G. Aniano, C. W. Engelbracht, J. L. Hinz, O. Krause, E. J. Montiel, H. Roussel, P. N. Appleton, L. Armus, P. Beirao, A. D. Bolatto, B. R. Brandl, D. Calzetti, A. F. Crocker, K. V. Croxall, B. T. Draine, M. Galametz, K. D. Gordon, B. A. Groves, C. -N. Hao, G. Helou, L. K. Hunt, B. D. Johnson, R. C. Kennicutt, J. Koda, A. K. Leroy, Y. Li, S. E. Meidt, A. E. Miller, E. J. Murphy, N. Rahman, H. -W. Rix, K. M. Sandstrom, M. Sauvage, E. Schinnerer, R. A. Skibba, J. -D. T. Smith, F. S. Tabatabaei, F. Walter, C. D. Wilson, M. G. Wolfire, S. Zibetti
New far-infrared and sub-millimeter photometry from the Herschel Space
Observatory is presented for 61 nearby galaxies from the Key Insights on Nearby
Galaxies: A Far-Infrared Survey with Herschel (KINGFISH) sample. The
spatially-integrated fluxes are largely consistent with expectations based on
Spitzer far-infrared photometry and extrapolations to longer wavelengths using
popular dust emission models. Dwarf irregular galaxies are notable exceptions,
as already noted by other authors, as their 500um emission shows evidence for a
sub-millimeter excess. In addition, the fraction of dust heating attributed to
intense radiation fields associated with photo-dissociation regions is found to
be (21+/-4)% larger when Herschel data are included in the analysis. Dust
masses obtained from the dust emission models of Draine & Li are found to be on
average nearly a factor of two higher than those based on single-temperature
modified blackbodies, as single blackbody curves do not capture the full range
of dust temperatures inherent to any galaxy. The discrepancy is largest for
galaxies exhibiting the coolest far-infrared colors.
View original:
http://arxiv.org/abs/1112.1093
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