中文
相关论文

相关论文: The Chemical Evolution of the Galaxy with Variable…

200 篇论文

The empirical differential metallicity distribution (EDMD) is deduced for (i) local thick disk stars; (ii) likely metal-weak thick disk stars; (iii) chemically selected local G dwarfs, with the corrections performed in order to take into…

天体物理学 · 物理学 2009-06-23 R. Caimmi

One of the most robust observations of the stellar initial mass function (IMF) is its near-universality in the Milky Way and neighboring galaxies. But recent observations of early-type galaxies can be interpreted to imply a bottom-heavy…

星系天体物理 · 物理学 2019-03-26 David Guszejnov , Philip F. Hopkins , Andrew S. Graus

The distribution of stellar masses that form in one star-formation event in a given volume of space is called the initial mass function (IMF). The IMF has been estimated from low-mass brown dwarfs to very massive stars. Combining IMF…

天体物理学 · 物理学 2009-11-07 Pavel Kroupa

The chemical abundances measured in stars of the Galactic bulge offer an unique opportunity to test galaxy formation models as well as impose strong constraints on the history of star formation and stellar nucleosynthesis. The aims of this…

星系天体物理 · 物理学 2015-05-20 Gabriele Cescutti , Francesca Matteucci

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…

宇宙学与河外天体物理 · 物理学 2015-06-11 Desika Narayanan , Romeel Davé

By means of chemo-photometric models for galaxies of different morhological types, we have carried out a detailed study of the history of element production by spheroidal and dwarf irregular galaxies. Spheroidal galaxies suffer a strong and…

天体物理学 · 物理学 2009-11-11 Francesco Calura , Francesca Matteucci

The stellar initial mass function (IMF) of early-type galaxies is the combination of the IMF of the stellar population formed in-situ and that of accreted stellar populations. Using as an observable the effective IMF $\alpha_{IMF}$, defined…

星系天体物理 · 物理学 2017-01-18 Alessandro Sonnenfeld , Carlo Nipoti , Tommaso Treu

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

Peaks and lulls in the star formation rate (SFR) over the history of the Galaxy produce plateaux and declines in the present day mass function (PDMF) where the main-sequence lifetime overlaps the age and duration of the SFR variation. These…

天体物理学 · 物理学 2009-11-13 Bruce G. Elmegreen , John Scalo

In this work, we investigate the implications of the Integrated Galaxy-wide stellar Initial Mass Function (IGIMF) approach in the framework of the semi-analytic model GAEA (GAlaxy Evolution and Assembly), which features a detailed treatment…

The Galaxy is in continuous elemental evolution. Since new elements produced by dying stars are delivered to the interstellar medium, the formation of new enerations of stars and planetary systems is influenced by this metal enrichment. We…

星系天体物理 · 物理学 2019-08-17 Em. M. Penteado , H. M. Cuppen , H. J Rocha-Pinto

We model the star formation history (SFH) and the chemical evolution of the Galactic disk by combining an infall model and a limit-cycle model of the interstellar medium (ISM). Recent observations have shown that the SFH of the Galactic…

天体物理学 · 物理学 2009-11-06 H. Hirashita , A. Burkert , T. T. Takeuchi

It is frequently debated in literature whether a "standard" Initial Mass Function (IMF) - meaning an IMF of the kind usually adopted to explain the chemical evolution in the local Solar Neighbourhood - can account for the observed metal…

天体物理学 · 物理学 2009-11-10 L. Portinari , A. Moretti , C. Chiosi , J. Sommer-Larsen

In this thesis, the field star Initial Mass Function (IMF) and chemical evolution parameters for the Milky Way (MW) are derived using a forward modelling technique in combination with Bayesian statistics. Starting from a local MM disc…

星系天体物理 · 物理学 2018-02-26 Jan Rybizki

Few topics in astronomy initiate such vigorous discussion as whether or not the initial mass function (IMF) of stars is universal, or instead sensitive to the initial conditions of star formation. The distinction is of critical importance:…

星系天体物理 · 物理学 2015-05-18 Nate Bastian , Kevin R. Covey , Michael R. Meyer

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…

In this paper we study the very early phases of the evolution of our Galaxy by means of a chemical evolution model which reproduces most of the observational constraints in the solar vicinity and in the disk. We have restricted our analysis…

天体物理学 · 物理学 2016-08-30 Cristina Chiappini , Francesca Matteucci , Timothy Beers , Ken'ichi Nomoto

The stellar initial mass function and the stellar lifetimes are basic ingredients of chemical evolution models, for which different recipes can be found in the literature. In this paper, we quantify the effects on chemical evolution studies…

天体物理学 · 物理学 2007-05-23 Donatella Romano , Cristina Chiappini , Francesca Matteucci , Monica Tosi

Recent evidence based independently on spectral line strengths and dynamical modelling point towards a non-universal stellar Initial Mass Function (IMF), probably implying an excess of low-mass stars in elliptical galaxies with a high…

宇宙学与河外天体物理 · 物理学 2015-06-16 Carsten Weidner , Ignacio Ferreras , Alexandre Vazdekis , Francesco La Barbera

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