Program: GS-2007A-Q-30

We propose to detect and characterize Giant HII Regions (GHIIRs) in galaxies available to telescopes in the Southern Hemispher and to analyze the properties of the ionized gas and determine the nature and evolutionary state of its source of energy. We propose to analyse the characteristics of bright HII regions selected from the catalogs by Feinstein (1997) and Gil de Paz et al. (2003). Narrow band imaging (Halfa, [SII], [OIII]) and adjacent continua has been obtained at LCO and will be used to study the total emission line fluxes, and GMOS long slit spectroscopy requested in this application will allow to observe emission lines used as diagnostic to analyse the physical conditions of the gas in the selected regions, which is related to the inner stellar population responsible for the gas excitation. For the objects in common, our results will complement those presented by Gil de Paz and Madore (2005). In this proposal we plan to combine the multiple modes available within GMOS in order to analyze longslit spectra from GHIIRs candidates flagged from their photometric properties and to perform an in-depth 2D spectroscopic study of two conspicuous knots within galaxies of our sample.