RAS Discussion Meeting Abstract

The Distribution of Dust in Nearby Spiral Galaxies

We present 450 micron and 850 micron continuum images of the nearby edge-on galaxy NGC 281. Our data are sufficiently sensitive (1 sigma of 13 mJy/beam and 3.5 mJy/beam at 450 microns and 850 microns respectively) to trace submm dust emission form 2/3 of the optical disk and also to detect dust 'chimneys' escaping from the main absorption layer up to z-heights of 2kpc. At both 450 microns and 850 microns, peak emission is associated with the nucleus but there are also 2 bright secondary maxima, one on either side of the nucleus, which probably consitute the limb of a ring with radius 4kpc.

The submm emission resembles the distribution of molecular gas rather than that of the atomic hydrogen. A comparison between the major axis profile at 850 microns with the corresponding profile at 60 microns (IRAS HiRes data) implies that cold dust, rather than warm grains, predominates at larger radii.

Paul Alton, Simone Bianchi & Jon Davies (University of Wales, Cardiff),

Richard Rand (University of New Mexico),

& Manolis Xilouris (University of Crete)