The interdependence between density PDF, CMF, and IMF and their relation with Mach number in simulations
Abstract
Context. The initial mass function (IMF) of stars and the corresponding cloud mass function (CMF), traditionally considered universal, exhibit variations that are influenced by the local environment. Notably, these variations are apparent in the distribution's tail, indicating a possible relationship between local dynamics and mass distribution. Aims. Our study was designed to examine how the gas PDF, the IMF, and the CMF depend on the local turbulence within the interstellar medium (ISM). Methods. We ran hydrodynamical simulations on small star-forming sections of the ISM under varying turbulence conditions, characterised by Mach numbers of 1, 3.5, and 10, and with two distinct mean densities. This approach allowed us to observe the effects of different turbulence levels on the formation of stellar and cloud masses.
Results. The study demonstrates a clear correlation between the dynamics of the cloud and the IMF. In environments with lower levels of turbulence likely dominated by gravitational collapse, our simulations showed the formation of more massive structures with a power-law gas PDF, leading to a top-heavy IMF and CMF. On the other hand environment dominated by turbulence result in a lognormal PDF and a Salpeter-like CMF and IMF. This indicates that the turbulence level is a critical factor in determining the mass distribution within star-forming regions.
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BibTeX
@article{nunezcastineyra2026interdependence,
title = {{The interdependence between density PDF, CMF, and IMF and their relation with Mach number in simulations}},
author = {A. Núñez-Castiñeyra and M. González and N. Brucy and P. Hennebelle and F. Louvet and F. Motte},
journal = {Astronomy \& Astrophysics - A\&A},
year = {2026},
month = sep,
doi = {10.1051/0004-6361/202453497},
url = {https://hal.science/hal-05742629v1},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - The interdependence between density PDF, CMF, and IMF and their relation with Mach number in simulations
AU - A. Núñez-Castiñeyra
AU - M. González
AU - N. Brucy
AU - P. Hennebelle
AU - F. Louvet
AU - F. Motte
PY - 2026
DA - 2026/09/08
JO - Astronomy & Astrophysics - A&A
DO - 10.1051/0004-6361/202453497
UR - https://hal.science/hal-05742629v1
AB - Context. The initial mass function (IMF) of stars and the corresponding cloud mass function (CMF), traditionally considered universal, exhibit variations that are influenced by the local environment. Notably, these variations are apparent in the distribution's tail, indicating a possible relationship between local dynamics and mass distribution. Aims. Our study was designed to examine how the gas PDF, the IMF, and the CMF depend on the local turbulence within the interstellar medium (ISM). Methods. We ran hydrodynamical simulations on small star-forming sections of the ISM under varying turbulence conditions, characterised by Mach numbers of 1, 3.5, and 10, and with two distinct mean densities. This approach allowed us to observe the effects of different turbulence levels on the formation of stellar and cloud masses. Results. The study demonstrates a clear correlation between the dynamics of the cloud and the IMF. In environments with lower levels of turbulence likely dominated by gravitational collapse, our simulations showed the formation of more massive structures with a power-law gas PDF, leading to a top-heavy IMF and CMF. On the other hand environment dominated by turbulence result in a lognormal PDF and a Salpeter-like CMF and IMF. This indicates that the turbulence level is a critical factor in determining the mass distribution within star-forming regions.
SN - 0004-6361
SN - 1432-0746
ER -