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The Mass Spectra of Cores in Turbulent Molecular Clouds and Implications for the Initial Mass Function

Javier Ballesteros-Paredes·Adriana Gazol·Jongsoo Kim·Ralf S. Klessen·Anne-Katharina Jappsen·Epimenio Tejero·.
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Abstract

We investigate the core mass distribution (CMD) resulting from numerical models of turbulent fragmentation of molecular clouds. In particular we study its dependence on the sonic root-mean-square Mach number $\Ms$. We analyze simulations with $\Ms$ ranging from 1 to 15 to show that, as $\Ms$ increases, the number of cores increases as well while their average mass decreases. This stems from the fact that high-Mach number flows produce many and strong shocks on intermediate to small spatial scales, leading to a highly-fragmented density structure. We also show that the CMD from purely turbulent fragmentation does not follow a single power-law, but it may be described by a function that changes continuously its shape, probably more similar to a log-normal function. The CMD in supersonic turbulent flows does not have a universal slope, and as consequence, cast some doubt on attempts to directly relate the CMD to a universal Initial Mass Function.

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Javier Ballesteros-Paredes, Adriana Gazol, Jongsoo Kim, Ralf S. Klessen, Anne-Katharina Jappsen, Epimenio Tejero, .. 2005-09-20. The Mass Spectra of Cores in Turbulent Molecular Clouds and Implications for the Initial Mass Function. https://doi.org/10.1086/498228

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