Gemini GMOS--IFU spectroscopy of the compact HII galaxies Tol 0104-388
  and Tol 2146-391: The dependence on the properties of the interstellar medium
  Using GMOS--IFU spectroscopic observations of the compact HII/BCD galaxies
Tol 0104-388 and Tol 2146-391, we study the spatial distribution of emission
lines, equivalent width EW(Hb), extinction c(Hb), ionization ratios
([OIII]5007/Hb, [SII]6717,6731/Ha and [NII]6584/Ha), kinematics, and the
chemical pattern (O/H, N/H and N/O) of the warm interstellar medium in these
galaxies. We also investigate a possible dependence of these properties on the
I(HeII4686)/I(Hb) ratio and find no significant correlation between these
variables. In fact, the oxygen abundances appear to be uniform in the regions
where the HeII4686 emission line was measured. It can be interpreted in the
sense that these correlations are related to global properties of the galaxies
and not with small patches of the interstellar medium. Although a possible weak
N/H gradient is observed in Tol 2146-391, the available data suggest that the
metals from previous star-formation events are well mixed and homogeneously
distributed through the optical extent of these galaxies. The spatial constancy
of the N/O ratio might be attributed to efficient transport and mixing of
metals by starburst-driven super-shells, powered by a plethora of unresolved
star cluster in the inner part of the galaxies. This scenario agrees with the
idea that most of the observed HeII4686 emission line, in our sample of
galaxies, is produced by radiative shocks.
