Ionized Gas in the Irr Galaxy IC 10: The Emission Spectrum and
  Ionization Sources
  We present the results of observations of the Irr galaxy IC 10 at the 6-m SAO
telescope with the panoramic Multi-Pupil Fiber Spectrograph (MPFS). Based on
the results of these observations and our long-slit spectroscopy performed
previously, we have investigated the ionized-gas emission spectrum in the
region of intense star formation and refined the gas metallicity estimates. We
show that the "diagnostic diagrams" constructed from our observations agree
best with the new improved ionization models by Martin-Manjon et al. Using
these models, we have determined the electron density and gas ionization
parameter and ionizing-cluster characteristics, the age and mass, from the
spectra of the investigated HII regions. The cluster age and mass are shown to
be within the ranges 2.5 - 5 Myr and (0.2 - 1)*10^5 M(sun), respectively.
