author={Bruce G. Elmegreen},
  journal={The Astrophysical Journal},
  • B. Elmegreen
  • Published 23 May 2000
  • Physics
  • The Astrophysical Journal
Statistical sampling from the stellar initial mass function (IMF) for all star-forming regions in the Galaxy would lead to the prediction of ~1000 M☉ stars unless there is a rapid turn-down in the IMF beyond several hundred solar masses. Such a turn-down is not necessary for dense clusters because the number of stars sampled is always too small. Although no upper mass limits to star formation have ever been observed, a theory for the IMF should be able to explain the lack of ~1000 M☉ stars in… 

Figures from this paper

Evidence for a fundamental stellar upper mass limit from clustered star formation
The observed masses of the most massive stars do not surpass about 150 M ○. . This may either be a fundamental upper mass limit which is defined by the physics of massive stars and/or their
The maximum stellar mass, star-cluster formation and composite stellar populations
We demonstrate that the mass of the most massive star in a cluster correlates non-trivially with the cluster mass. A simple algorithm, according to which a cluster is filled up with stars that are
The stellar and sub-stellar IMF of simple and composite populations
The current knowledge on the stellar IMF is documented. It appears to become top-heavy when the star-formation rate density surpasses about 0.1Msun/(yr pc^3) on a pc scale and it may become
An upper limit to the masses of stars
There is an absence of stars with initial masses greater than 130 M [circdot] in the Arches cluster, whereas the typical mass function predicts 18.5; it is concluded that this indicates a firm limit of 150‬M [ Circdot] for stars.
The Initial Mass Function of Young Open Clusters in the Galaxy: A Preliminary Result
Abstract 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 Range of Variation of the Mass of the Most Massive Star in Stellar Clusters Derived from 35 Million Monte Carlo Simulations
A growing fraction of Simple Stellar Population (SSP) models, in an aim to create more realistic simulations capable of including stochastic variation in their outputs, begin their simulations with a
Cluster Density and the IMF
Observed variations in the IMF are reviewed with an emphasis on environmental density. The remote field IMF studied in the LMC by several authors is clearly steeper than most cluster IMFs, which have
Star-Formation Rates of Galaxies
The measured star-formation rates (SFRs) of galaxies comprise an important constraint on galaxy evolution and also on their cosmological boundary conditions. Any available tracer of the SFR depends
Models for the Formation of Massive Stars
The formation of massive stars is currently an unsolved problems in astrophysics. Understanding the formation of massive stars is essential because they dominate the luminous, kinematic, and chemical
Massive stars: their birth sites and distribution
Abstract The stellar IMF has been found to be an invariant Salpeter power-law ( α =2.35) above about 1 M ⊙ , but at the same time a massive star typically has more than one companion. This constrains


A Prediction of Brown Dwarfs in Ultracold Molecular Gas
A recent model for the stellar initial mass function (IMF), in which the stellar masses are randomly sampled down to the thermal Jeans mass from hierarchically structured prestellar clouds, predicts
The Initial Stellar Mass Function from Random Sampling in a Turbulent Fractal Cloud
The initial mass function (IMF) for stars is proposed to result from two distinct physical processes that determine its shape separately in two intervals of mass: random sampling of mass in a fractal
Two stellar mass functions combined into one by the random sampling model of the initial mass function
The turnover in the stellar initial mass function (IMF) at low mass suggests the presence of two independent mass functions that combine in different ways above and below a characteristic mass given
A Theory of the IMF for Star Formation in Molecular Clouds
We present models for the initial mass function (IMF) for stars forming within molecular clouds. These models use the idea that stars determine their own masses through the action of powerful stellar
IMF in starburst regions
There is growing evidence that the Initial Mass function (IMF) appears to be strongly weighted towards high-mass OB stars in certain regions where star formation occurs in a burst. Here, I define a
The Initial Mass Function of Low-Mass Stars and Brown Dwarfs in Taurus
By combining deep optical imaging and infrared spectroscopy with data from the Two-Micron All-Sky Survey (2MASS) and from previous studies (e.g., Briceno et al.), I have measured the initial mass
The Initial mass function and stellar birthrate in the solar neighborhood
We examine the initial mass function (IMF) and time history of the stellar birthrate in the solar neighborhood assuming a time-independent IMF. The present-day mass function is constructed from the
The Stellar Initial Mass Function from Random Sampling in Hierarchical Clouds. II. Statistical Fluctuations and a Mass Dependence for Starbirth Positions and Times
Observed variations in the slope of the stellar initial mass function (IMF) are shown to be consistent with a previously introduced model in which the protostellar gas is randomly sampled from clouds
The Intermediate-mass Stellar Population of the Large Magellanic Cloud Cluster NGC 1818 and the Universality of the Stellar Initial Mass Function*
We present stellar photometry from Hubble Space Telescope images of NGC 1818, a young populous star cluster in the Large Magellanic Cloud. The cluster stars in both the core and the outlying regions
Star Formation in a Crossing Time
Observations suggest that star formation occurs in only one or two crossing times for a range of scales spanning a factor of ~1000. These observations include (1) measurements of embedded cluster