A simple model to interpret the ultraviolet, optical and infrared emission from galaxies

We present a simple, largely empirical but physically motivated model to interpret the mid-and far-infrared spectral energy distributions of galaxies consistently with the emission at ultraviolet, optical and near-infrared wavelengths. Our model relies on an existing angle-averaged prescription to compute the absorption of starlight by dust in stellar birth clouds and in the ambient interstellar medium (ISM) in galaxies. We compute the spectral energy distribution of the power reradiated by dust in stellar birth clouds as the sum of three components: a component of polycyclic aromatic hydrocarbons (PAHs); a mid-infrared continuum characterizing the emission from hot grains at temperatures in the range 130-250…

• NA
  National Aeronautics and Space Administration
• CI
  California Institute of Technology
• JP
  Jet Propulsion Laboratory