ИСТИНА

Massive stars shape the interstellar medium (ISM) and affect the ongoing star formation in the galaxy through several channels: supernovae explosions, stellar wind, radiative and thermal pressures. The importance of the particular mechanisms of stellar feedback is a subject of extensive studies for the last several decades. The stellar feedback is crucial ingredient in the state of the art cosmological simulations. Therefore it is especially important to quantify (from observations) the role of stellar feedback in the low metallicity environment -- the conditions that resemble the early Universe. In our work, we analyzed the kinematics of the ionized and atomic gas in the nearby (D ~ 1.4 Mpc) metal-poor (metallicity ~7% of solar) star-forming dwarf galaxies Sextans A and Sextans B and linked the properties of their ISM to that of the young massive stars. Based on our high spectral resolution Fabry-Perot observations, we identified numerous expanding superbubbles with sizes of 30-300 pc. From the analysis of the gas ionization condition and the properties of the young stars (identified from the archival HST data), we conclude that some of these bubbles are probably driven by recent supernovae explosions, while significant contribution of pre-supernovae feedback is required to explain the observed kinematics of the rest of them (despite their low metallicity). In Sextans A we discovered a large discrepancy in the neutral and ionized gas kinematics resulted from the stellar feedback-driven galactic wind. Overall, the ionized gas kinematics in Sextans A and Sextans B is highly affected by the feedback from several generations of massive stars.