Mapping the properties of blue compact dwarf galaxies: integral field
  spectroscopy with PMAS
  (Abridged) We perform integral field spectroscopy of a sample of Blue compact
dwarf (BCD) galaxies with the aim of analyzing their morphology, the spatial
distribution of some of their physical properties (excitation, extinction, and
electron density) and their relationship with the distribution and evolutionary
state of the stellar populations. Integral field spectroscopy observations of
the sample galaxies were carried out with the Potsdam Multi-Aperture
Spectrophotometer (PMAS) at the 3.5 m telescope at Calar Alto Observatory. An
area 16 arcsec x 16 arcsec in size was mapped with a spatial sampling of 1
arcsec x 1 arcsec. We obtained data in the 3590-6996 Angstroms spectral range,
with a linear dispersion of 3.2 Angstroms per pixel. From these data we built
two-dimensional maps of the flux of the most prominent emission lines, of two
continuum bands, of the most relevant line ratios, and of the gas velocity
field. Integrated spectra of the most prominent star-forming regions and of
whole objects within the FOV were used to derive their physical parameters and
the gas metal abundances. Six galaxies display the same morphology both in
emission line and in continuum maps; only in two objects, Mrk 32 and Tololo
1434+032, the distributions of the ionized gas and of the stars differ
considerably. In general the different excitation maps for a same object
display the same pattern and trace the star-forming regions, as expected for
objects ionized by hot stars; only the outer regions of Mrk 32, I Zw 123 and I
Zw 159 display higher [SII]/Halpha values, suggestive of shocks. Six galaxies
display an inhomogeneous dust distribution. Regarding the kinematics, Mrk 750,
Mrk 206 and I Zw 159 display a clear rotation pattern, while in Mrk 32, Mrk 475
and I Zw 123 the velocity fields are flat.
