Previous
abstract 
Next abstract
Lyman continuum fluxes for O stars and early B stars (spectral type B0-B2) are derived from H$\alpha$ and H$\beta$ measurements of HII regions and compared with those predicted by stellar atmospheres models. This is the first extensive application of the Zanstra method to HII regions of B--stars. Diameters and electron densities of observed HII regions are estimated.
A number of HII regions, surrounding O and B stars were observed using wide-field Fabry-Perot scanning interferometers. This technique allows to observe extended HII regions of relatively bright stars. Balmer--$\alpha$ measurements of HII regions of several selected early type B-stars (B0-B2) were carried out during fall-winter 1992 with University of Wisconsin large aperture Fabry-Perot spectrometer and combined with the results of observations, carried out previously primarily on O stars.
