English
Related papers

Related papers: The Initial Mass Function and its Variation

200 papers

When a detailed model of a stellar population is unavailable, it is most common to assume that stellar masses are independently and identically distributed according to some distribution: the universal initial mass function (IMF). However,…

The stellar initial mass function (IMF) is a fundamental property of star formation, offering key insight into the physics driving the process as well as informing our understanding of stellar populations, their by-products, and their…

Astrophysics of Galaxies · Physics 2019-03-14 M. W. Hosek , J. R. Lu , M. Andersen , T. Do , D. Kim , N. Z. Rui , P. Boyle , B. F. Williams , S. Chakrabarti , R. L. Beaton

Analyses of strong gravitational lenses, galaxy-scale kinematics, and absorption line stellar population synthesis (SPS) have all concluded that the stellar initial mass function (IMF) varies within the massive early-type galaxy (ETG)…

Astrophysics of Galaxies · Physics 2017-11-29 Alexa Villaume , Jean Brodie , Charlie Conroy , Aaron J. Romanowsky , Pieter van Dokkum

The hypothesis of a universal initial mass function (IMF) -- motivated by observations in nearby stellar systems -- has been recently challenged by the discovery of a systematic variation of the IMF with the central velocity dispersion,…

Observations have not yielded convincing results concerning the form of the stellar initial mass function (IMF) or its variations in space and time, so it is proposed that theoretical models may provide useful guidance. Several classes of…

Astrophysics · Physics 2009-09-25 John Scalo

We present a combined analysis of the low-mass Initial Mass Function (IMF) for seven star forming regions. We first demonstrate that the ratios of stars to brown dwarfs are consistent with a single underlying IMF. Assuming the underlying…

Astrophysics · Physics 2009-11-13 M. Andersen , M. R. Meyer , J. Greissl , A. Aversa

We derive a semi-empirical galactic initial mass function (IMF) from observational constraints. We assume that the star formation rate in a galaxy can be expressed as the product of the IMF, $\psi (m)$, which is a smooth function of mass…

Astrophysics of Galaxies · Physics 2015-05-20 Antonio Parravano , Christopher F. McKee , David J. Hollenbach

The debate about the universality of the stellar initial mass function (IMF) revolves around two competing lines of evidence. While measurements in the Milky Way, an archetypal spiral galaxy, seem to support an invariant IMF, the observed…

The initial mass function (IMF) is one of the most important functions in astrophysics because it is key to reconstructing the cosmological matter cycle, understanding the formation of super-massive black holes, and deciphering the light…

Astrophysics of Galaxies · Physics 2024-12-30 Pavel Kroupa , Eda Gjergo , Tereza Jerabkova , Zhiqiang Yan

I review efforts to determine the form and any lower limit to the initial mass function in the Galactic disk, using observations of low-mass stars and brown dwarfs in the field, young clusters and star forming regions. I focus on the…

Solar and Stellar Astrophysics · Physics 2015-06-05 R. D. Jeffries

Recent studies seem to suggest that the stellar initial mass function (IMF) in early-type galaxies might be different from a classical Kroupa or Chabrier IMF, i.e. contain a larger fraction of the total mass in low-mass stars. From a…

Astrophysics of Galaxies · Physics 2016-08-05 Clio Bertelli Motta , Paul C. Clark , Simon C. O. Glover , Ralf S. Klessen , Anna Pasquali

A number of recent studies have proposed that the stellar initial mass function (IMF) of early type galaxies varies systematically as a function of galaxy mass, with higher mass galaxies having bottom heavy IMFs. These bottom heavy IMFs…

Some ultra-compact dwarf galaxies have large dynamical mass to light (M/L) ratios and also appear to contain an overabundance of LMXB sources, and some Milky Way globular clusters have a low concentration and appear to have a deficit of…

Astrophysics of Galaxies · Physics 2020-03-18 Pavel Kroupa

The initial mass function (IMF) is an essential tool with which to study star formation processes. We have initiated the photometric survey of young open clusters in the Galaxy, from which the stellar IMFs are obtained in a homogeneous way.…

Astrophysics of Galaxies · Physics 2015-11-05 Beomdu Lim , Hwankyung Sung , Hyeonoh Hur , Byeong-Gon Park

(abridged) The case can be made for a rather universal stellar IMF form that can be approximated by a two-part power-law function in the stellar regime. However, there exists a possible hint for a systematic variation with metallicity. A…

Astrophysics · Physics 2007-05-23 Pavel Kroupa

The current status of both the observational evidence and the theory of the stellar initial mass function (IMF) is reviewed, with particular attention to the two basic, apparently universal features shown by all observations of nearby…

Astrophysics · Physics 2007-05-23 Richard B. Larson

We investigate how different stellar initial mass functions (IMFs) can affect the mass loss and survival of star clusters. We find that IMFs with radically different low-mass cut-offs (between 0.1 and 2 Msun) do not change cluster…

Solar and Stellar Astrophysics · Physics 2015-06-22 M. B. N. Kouwenhoven , S. P. Goodwin , R. de Grijs , M. Rose , Sungsoo S. Kim

The stellar initial mass function (IMF) seems to be variable and not universal, as argued in the literature in the last three decades. Several relations among the low-mass end of the IMF slope and other stellar population, photometric or…

Astrophysics of Galaxies · Physics 2021-01-13 C. E. Barbosa , C. Spiniello , M. Arnaboldi , L. Coccato , M. Hilker , T. Richtler

Two varieties of the universal stellar initial mass function (IMF) viz., the Kroupa and the Chabrier IMF, have emerged over the last decade to explain the observed distribution of stellar masses. The possibility of the universal nature of…

Astrophysics of Galaxies · Physics 2015-06-05 S. Anathpindika

The origin of the stellar initial mass function (IMF) is a fundamental issue in the theory of star formation. It is generally fit with a composite power law. Some clues on the progenitors can be found in dense starless cores that have a…

Astrophysics of Galaxies · Physics 2015-09-21 Tingtao Zhou , Chelsea X. Huang , D. N. C. Lin , Matthias Gritschneder , Herbert Lau