English
Related papers

Related papers: Calibrated, cosmological hydrodynamical simulation…

200 papers

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…

Astrophysics of Galaxies · Physics 2020-10-07 Timothy A. Davis , Freeke van de Voort

We present an investigation about the shape of the initial mass function (IMF) of early-type galaxies (ETGs), based on a joint lensing and dynamical analysis, and on stellar population synthesis models, for a sample of 55 lens ETGs…

Astrophysics of Galaxies · Physics 2015-06-22 Silvia Posacki , Michele Cappellari , Tommaso Treu , Silvia Pellegrini , Luca Ciotti

Because direct measurements require resolved stellar populations including low-mass stars, determining the stellar initial mass function (IMF) has been a historically difficult problem even within our own Galaxy and impossible everywhere…

Astrophysics of Galaxies · Physics 2026-03-26 Charles L. Steinhardt , Carter Meyerhoff , Alexander J. Luening

We have studied the effects of various initial mass functions (IMFs) on the chemical evolution of the Sagittarius dwarf galaxy (Sgr). In particular, we tested the effects of the integrated galactic initial mass function (IGIMF) on various…

The spectral absorption lines in early-type galaxies contain a wealth of information regarding the detailed abundance pattern, star formation history, and stellar initial mass function (IMF) of the underlying stellar population. Using our…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Charlie Conroy , Pieter van Dokkum

Theoretical and indirect observational evidences suggest that stellar initial mass function (IMF) increases with redshift. On the other hand star formation rates (SFR) may be as high as 100 $M_{\odot}$ yr$^{-1}$ in star burst galaxies.…

Astrophysics of Galaxies · Physics 2015-08-06 Tanuka Chattopadhyay , Tuli De , Bharat Warlu , Asis Kumar Chattopadhyay

In this work we explore the effects of adopting initial mass functions (IMFs) variable in time on the chemical evolution of the Galaxy. In order to do that we adopt a chemical evolution model which assumes two main infall episodes for the…

Astrophysics · Physics 2009-10-31 Cristina Chiappini , Francesca Matteucci , Paolo Padoan

Recent results form the James Webb Space Telescope (JWST) report space densities for bright and massive galaxies at z>7 that far exceed expectations of theoretical models of galaxy formation, prompting a revision of our understanding of the…

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

In this work we explore the effects of adopting an initial mass function (IMF) variable in time on the chemical evolution of the Galaxy. In order to do that we adopt a chemical evolution model which assumes two main infall episodes for the…

Astrophysics · Physics 2016-01-27 Cristina Chiappini , Francesca Matteucci

Spectroscopic analyses of gravity-sensitive line strengths give growing evidence towards an excess of low-mass stars in massive early-type galaxies (ETGs). Such a scenario requires a bottom-heavy initial mass function (IMF). However, strong…

Astrophysics of Galaxies · Physics 2015-06-23 I. Ferreras , C. Weidner , A. Vazdekis , F. La Barbera

Much of our knowledge of galaxies comes from analysing the radiation emitted by their stars. It depends on the stellar initial mass function (IMF) describing the distribution of stellar masses when the population formed. Consequently…

There is good evidence that the centers of massive early-type galaxies have a bottom-heavy stellar initial mass function (IMF) compared to the IMF of the Milky Way. Here we study the radial variation of the IMF within such galaxies, using a…

Astrophysics of Galaxies · Physics 2017-05-31 Pieter van Dokkum , Charlie Conroy , Alexa Villaume , Jean Brodie , Aaron Romanowsky

Observational and theoretical arguments increasingly suggest that the initial mass function (IMF) of stars may depend systematically on environment, yet most galaxy formation models to date assume a universal IMF. Here we investigate…

Astrophysics of Galaxies · Physics 2018-11-26 Thales A. Gutcke , Volker Springel

We describe the use of our chemical evolution model to reproduce the abundance patterns observed in a catalog of elliptical galaxies from the SDSS DR4. The model assumes ellipticals form by fast gas accretion, and suffer a strong burst of…

Astrophysics of Galaxies · Physics 2018-01-10 Carlo Maria De Masi , Francesca Matteucci , Fiorenzo Vincenzo

We perform Jeans anisotropic modeling (JAM) on elliptical and spiral galaxies from the MaNGA DR13 sample. By comparing the stellar mass-to-light ratios estimated from stellar population synthesis (SPS) and from JAM, we find a similar…

The stellar initial mass function (IMF) is commonly assumed to be an invariant probability density distribution function of initial stellar masses being represented by the canonical IMF. As a consequence the galaxy-wide IMF (gwIMF), defined…

Astrophysics of Galaxies · Physics 2018-11-28 T. Jerabkova , A. H. Zonoozi , P. Kroupa , G. Beccari , Z. Yan , A. Vazdekis , Z. -Y. Zhang

We investigate the impact of an environment-dependent galaxy-wide stellar initial mass function (gwIMF) on the baryonic Tully-Fisher relation (BTFR). The integrated galaxy-wide IMF (IGIMF) theory, which incorporates variations in stellar…

Astrophysics of Galaxies · Physics 2025-07-18 Akram Hasani Zonoozi , Hosein Haghi , Pavel Kroupa , Sara Yousefizadeh , Zhiqiang Yan , Tereza Jerabkova , Eda Gjergo

Given a flurry of recent claims for systematic variations in the stellar initial mass function (IMF), we carry out the first inventory of the observational evidence using different approaches. This includes literature results, as well as…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Crescenzo Tortora , Aaron J. Romanowsky , Nicola R. Napolitano

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,…