Contents of: VI/111/./abstract/MTREWHEL_DUST_SED.abs

The following document lists the file abstract/MTREWHEL_DUST_SED.abs from catalogue VI/111.
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==> This proposal is an extension of the
grade 2 open time proposal JIDAVIES.DUSTYGAL
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Our aim is to measure the spectral energy distribution of dust at several
positions in spiral disks. We will be able to accurately determine the mass
fraction of dust at different temperatures, the total mass of dust, the
fraction of energy emitted by dust of different temperatures and the total
energy output of dust. We will also see how these properties vary with position
in the disk. This information will allow us to further investigate our initial
findings from ISO 200 micron observations of NGC 6946 which imply that strong
radial dust temperature gradients are present in disk galaxies which cannot be
detected using data from the IRAS satellite.
By comparing the total energy output accurately measured with LWS to that
measured using IRAS HiRes and ISO (ISOPHOT) observations at 12,25,60,100 and
200 microns we will be in position to create a set of `template' spectra
corresponding to a wide range of physical conditions encountered in galactic
disks.These will significantly increase the accuracy of our measurements of the
internal extinction in spiral galaxies with the JIDAVIES.DUSTYGAL program. The
total dust mass (and therefore dust-to-gas ratio) will be measured accurately
as a function of position. Current estimates of dust mass, based on IRAS data,
span over an order of magnitude.