2014/03/28 by Florent Renaud, Frédéric Bournaud, Katarina Kraljic +1 · 1 citation
Physics and Astronomy · #astro-ph.GA
paper · pdf · doi:10.1093/mnrasl/slu050
Accepted for publication in MNRAS Letters
arxiv created 2014/03/28 · arxiv updated 2015/06/19
Using parsec-resolution simulations of a typical galaxy merger, we study the triggering of starbursts by connecting the (inter-)galactic dynamics to the structure of the interstellar medium. The gravitational encounter between two galaxies enhances tidal compression over large volumes, which increases and modifies the turbulence, in particular its compressive mode with respect to the solenoidal one. This generates an excess of dense gas leading to intense star formation activity. Along the interaction, the compressive turbulence modifies the efficiency of gas-to-star conversion which, in the Schmidt-Kennicutt diagram, drives the galaxies from the sequence of discs to that of starbursts.