Does turbulence determine the initial mass function?
Monthly Notices of the Royal Astronomical Society
Oxford University Press (OUP)
© 2016 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society
We test the hypothesis that the initial mass function (IMF) is determined by the density probability distribution function (PDF) produced by supersonic turbulence. We compare 14 simulations of star cluster formation in 50 M molecular cloud cores where the initial turbulence contains either purely solenoidal or purely compressive modes, in each case resolving fragmentation to the opacity limit to determine the resultant IMF. We find statistically indistinguishable IMFs between the two sets of calculations, despite a factor of 2 difference in the star formation rate and in the standard deviation of log (ρ). This suggests that the density PDF, while determining the star formation rate, is not the primary driver of the IMF.
We thank the anonymous referee for comments which have improved the paper. We acknowledge CPU time on gSTAR, funded by Swinburne University and the Australian Government. This project was funded via Australian Research Council Discovery Project DP130102078 and Future Fellowship FT130100034. We used SPLASH (Price 2007).
This is the author accepted manuscript. The final version is available from Oxford University Press via the DOI in this record.
Vol. 465, Iss. 1, pp. 105-110