Does turbulence determine the initial mass function?

2016/10/26 by David Liptai, Daniel J. Price, James Wurster +1 · 1 citation
Chemical Engineering · Physics and Astronomy · #Advanced Combustion Engine Technologies #Astrophysics #Astrophysics and Star Formation Studies #Initial mass function #Mechanics #Molecular cloud #Physics #Probability density function #Solenoidal vector field #Star formation #Stars #Statistical physics #Statistics #Stellar, planetary, and galactic studies #Supersonic speed #Turbulence #astro-ph.GA #astro-ph.SR

paper · pdf · doi:10.1093/mnras/stw2770

6 pages, 7 figures, accepted to MNRAS

arxiv created 2016/10/26 · openalex publication_date 2016/10/27 · arxiv updated 2016/12/07 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05

Abstract

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.

Citations

• The stellar initial mass function, core mass function and the last-crossing distribution
• RADIATION FEEDBACK, FRAGMENTATION, AND THE ENVIRONMENTAL DEPENDENCE OF THE INITIAL MASS FUNCTION
• Stellar, brown dwarf and multiple star properties from hydrodynamical simulations of star cluster formation
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• Accretion and the stellar mass spectrum in small clusters
• The formation of star clusters - II. 3D simulations of magnetohydrodynamic turbulence in molecular clouds
• Gravitational Collapse in Turbulent Molecular Clouds. II. Magnetohydrodynamical Turbulence
• Star Formation in Clusters: A Survey of Compact Millimeter-Wave Sources in the Serpens Core
• On the variation of the initial mass function
• Galactic Stellar and Substellar Initial Mass Function

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