RAS: The turbulent birth of stars in merging galaxies

[MargaritaMc]

Why do stars form when galaxies merge? I confess that although I knew that this was so, I hadn't realised that there was a mystery about WHY stars formed in these starburst galaxies.
This article in the MNRASL explains the issue and the solution.

http://www.ras.org.uk/news-and-press/ne ... g-galaxies

Using state of the art computer simulations, a team of French astrophysicists have for the first time explained a long standing mystery: why surges of star formation (so called ‘starbursts’) take place when galaxies collide. The scientists, led by Florent Renaud of the AIM institute near Paris in France, publish their results in a letter to the journal Monthly Notices of the Royal Astronomical Society.
Stars form when the gas inside galaxies becomes dense enough to collapse, usually under the effect of gravitation. When galaxies merge however, this increases the random motions of their gas generating whirls of turbulence which should hinder the collapse of the gas. Intuitively this turbulence should then slow down or even shut down the formation of stars, but in reality astronomers observe the opposite.

The full paper is available here (free):

http://mnrasl.oxfordjournals.org/content/442/1/L33.full

http://arxiv.org/abs/1403.7316