The radial extinction profiles of late-type galaxies

Abstract

We have used UV (FOCA) and FIR (IRAS) images of six nearby late type galaxies to study the radial variation of the UV extinction (deduced from the FIR/UV ratio). We compare the UV extinction gradient with other extinction indicators (Balmer decrement) and search for a relation between the extinction, the metallicity and the gas surface density among our galaxies. We detect in our small sample a clear relation between extinction and metallicity. These observed relations are used to calibrate an empirical recipe useful for extinction correction in the UV, visible and near-infrared images of late type galaxies.