open access

https://hdl.handle.net/2115/57653

Environmental dependence of star formation induced by cloud collisions in a barred galaxy

英語

galaxies: structure

2014-11-21

Oxford University Press

Monthly notices of the Royal Astronomical Society

445(1)

L65-L69

Cloud collision has been proposed as a way to link the small-scale star formation process with the observed global relation between the surface star formation rate and gas surface density. We suggest that this model can be improved further by allowing the productivity of such collisions to depend on the relative velocity of the two clouds. Our adjustment implements a simple step function that results in the most successful collisions being at the observed velocities for triggered star formation. By applying this to a high-resolution simulation of a barred galaxy, we successfully reproduce the observational result that the star formation efficiency (SFE) in the bar is lower than that in the spiral arms. This is not possible when we use an efficiency dependent on the internal turbulence properties of the clouds. Our results suggest that high-velocity collisions driven by the gravitational pull of the clouds are responsible for the low bar SFE.

学術雑誌論文

Version of Record

This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society ©: 2014 The Authors Published by Oxford University Press on behalf of The Royal Astronomical Society. All rights reserved.

0035-8711

1365-2966