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Modeling Spiral Galaxy Surface Luminosity to Explain Non-Uniform Inclination Distributions
  • Jordan C Rozum, Utah State University
  • Shane L Larson

The distribution of spiral and bar galaxy inclination angles is expected to be uniform. However, analysis of several major galaxy catalogs shows this is not the case; galaxies oriented near edge-on are significantly more common in these catalogs. In an attempt to explain this discrepancy, we have developed a galaxy simulation code to compute the appearance of a spiral type galaxy as a function of its morphological parameters. We examine the dependence of observed brightness upon inclination angle by using smooth luminous mass density and ISM density distributions. The luminous component is integrated along a particular line of sight, thus producing a mass distribution, from which a surface luminosity profile is derived. The ISM component is integrated alongside the luminous component to account for light extinction. Preliminary data ignoring extinction demonstrate trends matching the observed small inclination distribution. We reproduce overall spiral galaxy morphology and outline the ongoing validation process.

Publication Date
March, 2013
Citation Information
Jordan C Rozum and Shane L Larson. "Modeling Spiral Galaxy Surface Luminosity to Explain Non-Uniform Inclination Distributions" (2013)
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