Bibcode
Castaneda, H. O.; Vilchez, J. M.; Copetti, M. V. F.
Bibliographical reference
Astronomy and Astrophysics (ISSN 0004-6361), vol. 260, no. 1-2, p. 370-380.
Advertised on:
7
1992
Citations
36
Refereed citations
28
Description
We report the results of a systematic study on the spatial variation of
the electron density in a selected group of bright giant H II complexes
in the galaxies M 101, M 51, and NGC 6822. Density values for the
ionized gas of the regions have been obtained from the forbidden S II
6717/6731 ratio, using long-slit spectrophotometry at high spectral and
spatial resolution. Our study shows evidence that some of the regions
present gradients in the distribution of the ionized gas, the brightest
zones being associated with the maximum electron density values. For
those cases where density variation is defined, different models that
describe the internal gas density distribution have been considered and
compared with the observations. We conclude that more realistic
theoretical models of nebulae should take into account the internal
density gradients within the regions.