A multiple power-law distribution for initial mass functions

Authors

Christopher Essex, The University of Western Ontario
Shantanu Basu, The University of Western OntarioFollow
Janett Prehl, Technische Universität Chemnitz
Karl Heinz Hoffmann, Technische Universität Chemnitz

Document Type

Article

Publication Date

1-1-2020

Journal

Monthly Notices of the Royal Astronomical Society

Volume

494

Issue

2

First Page

1579

Last Page

1586

URL with Digital Object Identifier

10.1093/MNRAS/STAA755

Abstract

We introduce a new multi-power-law distribution for the initialmass function (IMF) to explore its potential properties. It follows on prior work that introduced mechanisms accounting for mass accretion in star formation, developed within the framework of general evolution equations for the mass distribution of accreting and non-accreting (proto)stars. This paper uses the same fundamental framework to demonstrate that the interplay between a mass-dependent and a time-dependent step-like dropout rate from accretion leads to IMFs that exhibit multiple power laws for an exponential mass growth. While the mass-dependent accretion and its dropout is intrinsic to each star, the time-dependent dropout might be tied to a specific history such as the rapid consumption of nebular material by nearby stars or the sweeping away of some material by shock waves. The time-dependent dropout folded into the mass-dependent process of star formation is shown to have a significant influence on the IMFs.