Ionization conditions in the central Giant H II Region of NGC 5253

Abstract

We are carrying out a detailed 2D spectroscopic study of the central 210× 130 pc of the blue compact dwarf (BCD) galaxy NGC 5253. This contribution presents the ionization conditions and chemical abundance patterns for the different kinematic components of the ionized gas detected in our previous work. All the kinematic components present an excess in nitrogen abundance. In particular, the broad velocity component has larger excess than the narrow one by a factor of ∼1.4 ± 0:4 which is consistent with a scenario for the Giant H II Region where the broad component of the emission lines traces the material expelled by the two central Super Star Clusters while the narrow one is associated to previously existing ionized gas. © Springer-Verlag Berlin Heidelberg 2012.