Simulations of Dust in Interacting Galaxies

Patrik Jonsson; T. J. Cox; Joel R. Primack

doi:10.1063/1.1913946

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arXiv · astro-ph/0412112

Simulations of Dust in Interacting Galaxies

Patrik Jonsson·T. J. Cox·Joel R. Primack

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Abstract

A new Monte-Carlo radiative-transfer code, Sunrise, is used to study the effects of dust in N-body/hydrodynamic simulations of interacting galaxies. Dust has a profound effect on the appearance of the simulated galaxies. At peak luminosities, about 90% of the bolometric luminosity is absorbed, and the dust obscuration scales with luminosity in such a way that the brightness at UV/visual wavelengths remains roughly constant. A general relationship between the fraction of energy absorbed and the ratio of bolometric luminosity to baryonic mass is found. Comparing to observations, the simulations are found to follow a relation similar to the observed IRX-Beta relation found by Meurer et al (1999) when similar luminosity objects are considered. The highest-luminosity simulated galaxies depart from this relation and occupy the region where local (U)LIRGs are found. This agreement is contingent on the presence of Milky-Way-like dust, while SMC-like dust results in far too red a UV continuum slope to match observations. The simulations are used to study the performance of star-formation indicators in the presence of dust. The far-infrared luminosity is found to be reliable. In contrast, the H-alpha and far-UV luminosity suffer severely from dust attenuation, and dust corrections can only partially remedy the situation.

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BibTeX RIS

Patrik Jonsson, T. J. Cox, Joel R. Primack. 2004-12-05. Simulations of Dust in Interacting Galaxies. https://doi.org/10.1063/1.1913946

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