The influence of the cloud virial parameter on the initial mass function.

Crucial for star formation is the interplay between gravity and turbulence. The observed cloud virial parameter, |$\alpha _{\mathrm{vir}}$|⁠ , which is the ratio of twice the turbulent kinetic energy to the gravitational energy, is found to vary significantly in different environments, where the scatter among individual star-forming clouds can exceed an order of magnitude. Therefore, a strong dependence of the initial mass function (IMF) on |$\alpha _{\mathrm{vir}}$| may challenge the notion of a universal IMF. To determine the role of |$\alpha _{\mathrm{vir}}$| on the IMF, we compare the star-particle mass functions obtained in high-resolution magnetohydrodynamical simulations including jet and heating feedback, with |$\alpha _{\mathrm{vir}}=0.0625$|⁠ , 0.125, and 0.5. We find that varying |$\alpha _{\mathrm{vir}}$| from |$\alpha _{\mathrm{vir}}\sim 0.5$| to |$\alpha _{\mathrm{vir}}< 0.1$| shifts the peak of the IMF to lower masses by a factor of |$\sim 2$| and increases the star formation rate by a similar factor. The dependence of the IMF and star formation rate on |$\alpha _{\mathrm{vir}}$| is non-linear, with the dependence subsiding at |$\alpha _{\mathrm{vir}}< 0.1$|⁠. Our study shows a systematic dependence of the IMF on |$\alpha _{\mathrm{vir}}$|⁠. Yet, it may not be measurable easily in observations, considering the uncertainties, and the relatively weak dependence found in this study. [ABSTRACT FROM AUTHOR]