Seminar 2018/10/03

Speaker: Dr. Michał Michałowski (Adam Mickiewicz University in Poznań, Poland)

Title: Massive stars formed in atomic hydrogen reservoirs

Date: 10:30-(11:30) 3 Oct., 2018 (Wed)

Place: ES640

Abstract:

I will discuss the process of gas inflow on galaxies and subsequent fuelling of star-formation. Using Australia Telescope Compact Array HI observations I will show that galaxies with anomalous local metallicity decrements (gamma-ray burst and relativistic supernova host galaxies) have substantial atomic gas reservoirs and significant off-centre gas clouds, suggesting recent gas inflows. Moreover, they are possibly deficient in molecular gas. This suggests that star formation in these galaxies may be fuelled by recent inflow of metal-poor atomic gas. This is controversial, but can happen in low-metallicity gas near the onset of star formation because cooling of gas (necessary for star formation) is faster than the HI-to-H2 conversion.