Abstract
In this contribution, we investigate the energetic processes associated to star formation activity in galaxies. In this way, spectroscopic data was used to discriminate those processes in a sample of starburst, luminous infrared galaxies-LIRGs, ultraluminous infrared galaxies-ULIRGs, and also in Seyfert, quasars and radio galaxies. We propose a new diagnostic diagram based on the polycyclic aromatic hydrocarbon features. The diagnostic diagram allow us to discriminate the behavior of starbursts and LIRGs-ULIRGs objects, taking into account the line emission of the PAHs, [NeII], [NeIII], and [OIV]. We found a good relation between [NeII] and PAH (11.2μ m+11.3μ m) in starburst, LINER and Seyfert samples.
