English
Related papers

Related papers: A Dual Power Law Distribution for the Stellar Init…

200 papers

The combination of a finite time-scale for star formation, rapid early stellar evolution and rapid stellar-dynamical processes imply that the stellar IMF cannot be inferred for any star cluster independently of its age (the Cluster IMF…

Astrophysics · Physics 2007-08-10 Pavel Kroupa

The stellar IMF has been found to be an invariant Salpeter power-law (alpha=2.35) above about 1 Msun, but at the same time a massive star typically has more than one companion. This constrains the possible formation scenarios of massive…

Astrophysics · Physics 2009-11-10 Pavel Kroupa

In the present work we examined the hypothesis that, a core mass function (CMF), such as the one deduced for cores in the Orion molecular cloud (OMC), could possibly be the primogenitor of the stellar initial mass function (IMF). Using the…

Astrophysics of Galaxies · Physics 2015-05-27 S. Anathpindika

We examine variations of the stellar initial mass function (IMF) in extreme environments within the formalism derived by Hennebelle \& Chabrier. We focus on conditions encountered in progenitors of massive early type galaxies and starburst…

Astrophysics of Galaxies · Physics 2015-06-23 G. Chabrier , P. Hennebelle , P. Charlot

The aim of this paper is to quantify the amplitude of the predicted plateau in [alpha/Fe] ratios associated with the most metal-poor stars of a galaxy. We assume that the initial mass function in galaxies is steeper if the star formation…

Astrophysics of Galaxies · Physics 2015-06-17 S. Recchi , F. Calura , B. K. Gibson , P. Kroupa

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 increasingly bottom-heavy with increasing…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Pavel Kroupa , Carsten Weidner , Jan Pflamm-Altenburg , Ingo Thies , Joerg Dabringhausen , Michael Marks , Thomas Maschberger

We measure the high-mass stellar initial mass function (IMF) from resolved stars in M33 young stellar clusters. Leveraging \textit{Hubble Space Telescope's} high resolving power, we fully model the IMF probabilistically. We first model the…

Star formation rates (SFR) larger than 1000 Msun/ yr are observed in extreme star bursts. This leads to the formation of star clusters with masses > 10^6 Msun in which crowding of the pre-stellar cores may lead to a change of the stellar…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Carsten Weidner , Pavel Kroupa , Jan Pflamm-Altenburg

We determine an absolute calibration of the initial mass function (IMF) of early-type galaxies, by studying a sample of 56 gravitational lenses identified by the SLACS Survey. Under the assumption of standard Navarro, Frenk & White dark…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 T. Treu , M. W. Auger , L. V. E. Koopmans , R. Gavazzi , P. J. Marshall , A. S. Bolton

The stellar initial mass function (IMF) is predicted to depend upon the temperature of gas in star-forming molecular clouds. The introduction of an additional parameter, $T_{IMF}$ , into photometric template fitting, allows galaxies to be…

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 investigate the effect of a metallicity-dependent stellar initial mass function (IMF), as deduced observationally by Martin-Navarro et al. (2015c), on the inferred stellar masses and star formation rates (SFRs) of a representative sample…

Astrophysics of Galaxies · Physics 2016-08-31 Bart Clauwens , Joop Schaye , Marijn Franx

We present velocity dispersion measurements of 20 Local Group stellar clusters (7 < log(age [yrs]) < 10.2) from integrated light spectra and examine the evolution of the stellar mass-to-light ratio, Upsilon_*. We find that the clusters…

Astrophysics of Galaxies · Physics 2015-06-11 Dennis Zaritsky , Janet E. Colucci , Peter M. Pessev , Rebecca A. Bernstein , Rupali Chandar

We review current theories for the origin of the Stellar Initial Mass Function (IMF) with particular focus on the extent to which the IMF can be considered universal across various environments. To place the issue in an observational…

The initial mass function (IMF) succinctly characterizes a stellar population, provides a statistical measure of the end result of the star-formation process, and informs our under- standing of the structure and dynamical evolution of…

Solar and Stellar Astrophysics · Physics 2011-07-25 Kevin R. Covey , Nate Bastian , Michael R. Meyer

We present constraints on the stellar initial mass function (IMF) in two ultra-faint dwarf (UFD) galaxies, Hercules and Leo IV, based on deep HST/ACS imaging. The Hercules and Leo IV galaxies are extremely low luminosity (M_V = -6.2, -5.5),…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 M. Geha , T. M. Brown , J. Tumlinson , J. Kalirai , J. D. Simon , E. Kirby , D. VandenBerg , R. M. Munoz , R. Avila , P. Guhathakurta , H. Ferguson

A wealth of observations recently challenged the notion of a universal stellar initial mass function (IMF) by showing evidences in favour of a variability of this statistical indicator as a function of galaxy properties. I present…

Astrophysics of Galaxies · Physics 2020-06-17 Fabio Fontanot

The stellar initial mass function (IMF) is a key property of stellar populations. There is growing evidence that the classical star-formation mechanism by the direct cloud fragmentation process has difficulties reproducing the observed…

Astrophysics of Galaxies · Physics 2015-02-19 Ingo Thies , Jan Pflamm-Altenburg , Pavel Kroupa , Michael Marks

This work aims to study the distribution of luminous and dark matter in Coma early-type galaxies. Dynamical masses obtained under the assumption that mass follows light do not match with the masses of strong gravitational lens systems of…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 J. Thomas , R. P. Saglia , R. Bender , D. Thomas , K. Gebhardt , J. Magorrian , E. M. Corsini , G. Wegner , S. Seitz

We examine the cosmic evolution of a stellar initial mass function (IMF) in galaxies that varies with the Jeans mass in the interstellar medium, paying particular attention to the K-band stellar mass to light ratio (M/L_K) of present-epoch…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Desika Narayanan , Romeel Davé