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Modelling the spectral energy distribution of galaxies from the ultraviolet to submillimeter

Cristina C. Popescu·Richard J. Tuffs
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Abstract

We present results from a new modelling technique which can account for the observed optical/NIR - FIR/submm spectral energy distributions (SEDs) of normal star-forming galaxies in terms of a minimum number of essential parameters specifying the star-formation history and geometrical distribution of stars and dust. The model utilises resolved optical/NIR images to constrain the old stellar population and associated dust, and geometry-sensitive colour information in the FIR/submm to constrain the spatial distributions of young stars and associated dust. It is successfully applied to the edge-on spirals NGC891 and NGC5907. In both cases the young stellar population powers the bulk of the FIR/sub-mm emission. The model also accounts for the observed surface brightness distribution and large-scale radial brightness profiles in NGC891 as determined using the Infrared Space Observatory (ISO) at 170 and 200 mcrions and at 850 micron using SCUBA.

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Cristina C. Popescu, Richard J. Tuffs. 2002-03-07. Modelling the spectral energy distribution of galaxies from the ultraviolet to submillimeter. https://arxiv.org/abs/astro-ph/0203123

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