Integral Field Spectroscopy of Local LCBGs: NGC 7673, a case study.
  Physical properties of star-forming regions
  Physical properties of the star-forming regions in the local Luminous Compact
Blue Galaxy NGC 7673 are studied in detail using 3D spectroscopic data taken
with the PPAK IFU at the 3.5-m telescope in CAHA. We derive integrated and
spatially resolved properties such as extinction, star formation rate and
metallicity for this galaxy. Our data show an extinction map with maximum
values located at the position of the main clumps of star formation showing
small spatial variations (E(B-V)_{t}=0.12-0.21 mag). We derive a H\alpha-based
SFR for this galaxy of 6.2 \pm 0.8 M_{\odot}/yr in agreement with the SFR
derived from infrared and radio continuum fluxes. The star formation is located
mainly in clumps A, B, C and F. Different properties measured in clump B makes
this region peculiar. We find the highest H\alpha luminosity with a SFR surface
density of 0.5 M_{\odot}yr^{-1}kpc^{-2} in this clump. In our previous work,
the kinematic analysis for this galaxy shows an asymmetrical ionized gas
velocity field with a kinematic decoupled component located at the position of
clump B. This region shows the absence of strong absorption features and the
presence of a Wolf-Rayet stellar population indicating this is a young burst of
massive stars. Furthermore, we estimate a gas metallicity of
12+log(O/H)=8.20\pm0.15 for the integrated galaxy using the R23 index. The
values derived for the different clumps with this method show small metallicity
variations in this galaxy, with values in the range 8.12 (for clump A) - 8.23
(for clump B) for 12+log(O/H). The analysis of the emission line ratios
discards the presence of any AGN activity or shocks as the ionization source in
this galaxy. Between the possible mechanisms to explain the starburst activity
in this galaxy, our 3D spectroscopic data support the scenario of an on-going
interaction with the possibility for clump B to be the dwarf satellite galaxy.
