Guseva N. Massive stars in the galaxies with active star formation and their interplay with interstellar medium

The thesis deals with study of new original sample of the blue compact galaxies (BCGs) obtained on the base of 6-m telescope SAO RAN observations. Heavy element abundances have been obtained with high accuracy. It was found that in the blue compact galaxies nitrogen is formed as a primary element, probably, produced by massive stars. ~20% of BCGs are found in voids. For the first time the estimate is made of the star metallicity in the BCGs. The comparison of the star and gas metallicities provides the evidence of selfenrichment of the star formation regions by heavy elements in most metal-deficient BCGs. The large sample of Wolf-Rayet galaxies (WR) based on the observations with 4-m and 2.1-m telescopes of the Kitt Peak observatory and 4.5-m telescope MMT (USA) was created and studied. For the first time the broad red bump is detected in 75% of WR galaxies. We propose a new technique for determining the numbers of WNL stars from newly identified emission lines. Using statistic of WR stars in the poorheavy element environment the constrain on the evolutionary population synthesis models are obtained. On the bases of spectroscopic and photometric observations with 10-m Keck II telescope, MMT, and 2.4-m Hubble space telescope (USA) we show that the BCGs with extremely low metallicity can be reproduced by models with only young stellar population not older than 100 Myr contradicting the usual claim that the absolutely young galaxies can be observed at the large redshifts exclusively.