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相关论文: Variations in the initial mass function in early-t…

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The stellar initial mass function (IMF) is a fundamental astrophysical quantity that impacts a wide range of astrophysical problems from heavy element distribution to galactic evolution to planetary system formation. However, the origin and…

太阳与恒星天体物理 · 物理学 2017-01-11 S. S. R. Offner

Star formation models predict that the metal-poor initial mass function (IMF) can be substantially different from that observed in the metal-rich Milky Way. This changeover occurs because metal-poor gas clouds cool inefficiently due to…

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…

星系天体物理 · 物理学 2015-05-20 Antonio Parravano , Christopher F. McKee , David J. Hollenbach

We investigate the time evolution and spatial variation of the stellar initial mass function (IMF) in star-forming disk galaxies by using chemodynamical simulations with an IMF model depending both on local densities and metallicities…

宇宙学与河外天体物理 · 物理学 2015-06-12 Kenji Bekki , Gerhardt R. Meurer

We present new observations of the three nearest early-type galaxy (ETG) strong lenses discovered in the SINFONI Nearby Elliptical Lens Locator Survey (SNELLS). Based on their lensing masses, these ETGs were inferred to have a stellar…

星系天体物理 · 物理学 2017-08-30 Andrew B. Newman , Russell J. Smith , Charlie Conroy , Alexa Villaume , Pieter van Dokkum

The observed stellar initial mass function (IMF) appears to vary, becoming bottom-heavy in the centres of the most massive, metal-rich early-type galaxies. It is still unclear what physical processes might cause this IMF variation. In this…

星系天体物理 · 物理学 2020-10-07 Timothy A. Davis , Freeke van de Voort

The stellar initial mass function (IMF) is commonly interpreted to be a scale-invariant probability density distribution function (PDF) such that many small clusters yield the same IMF as one massive cluster of the same combined number of…

星系天体物理 · 物理学 2023-02-22 Zhiqiang Yan , Tereza Jerabkova , Pavel Kroupa

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…

星系天体物理 · 物理学 2016-08-05 Clio Bertelli Motta , Paul C. Clark , Simon C. O. Glover , Ralf S. Klessen , Anna Pasquali

In this paper we investigate whether the stellar initial mass function of early-type galaxies depends on their host environment. To this purpose, we have selected a sample of early-type galaxies from the SPIDER catalogue, characterized…

星系天体物理 · 物理学 2018-03-14 Giulio Rosani , Anna Pasquali , Francesco La Barbera , Ignacio Ferreras , Alexandre Vazdekis

Growing evidence suggests that the stellar initial mass function (IMF) varies systematically across galaxies, deviating from the canonical Milky Way form. Such variations would modify the integrated nucleosynthetic yields, and hence the…

A universal stellar initial mass function (IMF) should not be expected from theoretical models of star formation, but little conclusive observational evidence for a variable IMF has been uncovered. In this paper, a parameterization of the…

星系天体物理 · 物理学 2022-06-01 Albert Sneppen , Charles L. Steinhardt , Hagan Hensley , Adam S. Jermyn , Basel Mostafa , John R. Weaver

The observed distribution of IMF shapes can be understood as statistical sampling from a universal IMF and variations that result from stellar-dynamical processes. However, young star clusters appear to have an IMF biased towards low-mass…

天体物理学 · 物理学 2007-05-23 Pavel Kroupa

We explore the stellar initial mass function (IMF) of a sample of 49 massive quiescent galaxies (MQGs) at 0.9$<$z$<$1.5. We base our analysis on intermediate resolution spectro-photometric data in the GOODS-N field taken in the…

The stellar initial mass function (IMF) describes the mass distribution of stars at the time of their formation and is of fundamental importance for many areas of astrophysics. The IMF is reasonably well constrained in the disk of the Milky…

宇宙学与河外天体物理 · 物理学 2015-05-20 Pieter van Dokkum , Charlie Conroy

The stellar initial mass function (IMF) describes the distribution of stellar masses that form in a given star formation event. The long main-sequence lifetimes of low-mass stars mean that the IMF in this regime (below $\sim 1…

Theoretical arguments and indirect observational evidence suggest that the stellar initial mass function (IMF) may evolve with time, such that it is more weighted toward high mass stars at higher redshift. Here we test this idea by…

天体物理学 · 物理学 2010-01-07 Pieter van Dokkum

Banerji et al. (2009) suggested that top-heavy stellar Initial Mass Functions (IMFs) in galaxies may arise when the interstellar physical conditions inhibit low-mass star formation, and they determined the physical conditions under which…

宇宙学与河外天体物理 · 物理学 2010-03-23 Manda Banerji , Serena Viti , David A. Williams

Recent work has suggested that the stellar initial mass function (IMF) is not universal, but rather is correlated with galaxy stellar mass, stellar velocity dispersion, or morphological type. In this paper, we investigate variations of the…

宇宙学与河外天体物理 · 物理学 2015-06-05 A. A. Dutton , T. Treu , B. J. Brewer , P. J. Marshall , M. W. Auger , M. Barnabe , D. C. Koo , A. S. Bolton , L. V. E. Koopmans

In this work, we want to find out if the IMF can be determined from colour images, integrated colours, or mass-to-light ratios, especially at high redshift, where galaxies cannot be resolved into individual stars, which would enable us to…

天体物理学 · 物理学 2008-11-26 P. Westera , M. Samland , S. J. Kautsch , R. Buser , K. Ammon

The Initial Mass Function (IMF) for massive galaxies can be constrained by combining stellar dynamics with strong gravitational lensing. However, this method is limited by degeneracies between the density profile of dark matter and the…