Inflow of atomic gas fuelling star formation

Michałowski, M. J.; Gentile, G.; Hjorth, J.; Krumholz, M. R.; Tanvir, N. R.; Kamphuis, P.; Burlon, D.; Baes, M.; Basa, S.; Berta, S.; Castro Cerón, J. M.; Crosby, D.; D'Elia, V.; Elliott, J.; Greiner, J.; Hunt, L. K.; Klose, S.; Koprowski, M. P.; Le Floc'h, E.; Malesani, D.; Murphy, T.; Nicuesa Guelbenzu, A.; Palazzi, E.; Rasmussen, J.; Rossi, A.; Savaglio, S.; Schady, P.; De Ugarte Postigo, A.; Watson, D.; Van Der Werf, P.; Vergani, S. D.; Xu, D.

Inflow of atomic gas fuelling star formation

Date

2015

Authors

Abstract

Gamma-ray burst host galaxies are deficient in molecular gas, and show anomalous metal-poor regions close to GRB positions. Using recent Australia Telescope Compact Array (ATCA) Hi observations we show that they have substantial atomic gas reservoirs. This suggests that star formation in these galaxies may be fuelled by recent inflow of metal-poor atomic gas. While this process is debated, it can happen in low-metallicity gas near the onset of star formation because gas cooling (necessary for star formation) is faster than the Hi-to-H2 conversion.