English
Related papers

Related papers: Simulating a White Dwarf-dominated Galactic Halo

200 papers

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

Recent observations and theories have presented a strong challenge to the universality of the stellar initial mass function (IMF) in extreme environments. A notable example has been found for starburst conditions, where evidence favours a…

Astrophysics of Galaxies · Physics 2024-05-10 Ziyi Guo , Zhi-Yu Zhang , Zhiqiang Yan , Eda Gjergo , Allison Man , R. J. Ivison , Xiaoting Fu , Yong Shi

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 pre-stellar clouds, predicts that regions of ultra-cold CO gas, such…

Astrophysics · Physics 2009-10-31 Bruce G. Elmegreen

Observations of mergers of multi-compact object systems offer insights to the formation processes of massive stars in globular clusters. Simulations of stellar clusters, may be used to understand and interpret observations. Simulations…

Astrophysics of Galaxies · Physics 2018-12-27 Indulekha Kavila , Megha Viswambharan

Growing evidence in recent years suggests a systematic variation of the stellar initial mass function (IMF), being top-heavy for starburst galaxies and possibly bottom-heavy for massive ellipticals. Galaxy chemical evolution simulations…

Astrophysics of Galaxies · Physics 2019-09-11 Zhiqiang Yan , Tereza Jerabkova , Pavel Kroupa , Alejandro Vazdekis

We use the relations between aperture stellar velocity dispersion (\sigma_ap), stellar mass (M_sps), and galaxy size (R_e) for a sample of \sim 150,000 early-type galaxies from SDSS/DR7 to place constraints on the stellar initial mass…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Aaron A. Dutton , Andrea V. Maccio' , J. Trevor Mendel , Luc Simard

The long-standing assumption that the stellar initial mass function (IMF) is universal has recently been challenged by a number of observations. Several studies have shown that a "heavy" IMF (e.g., with a Salpeter-like abundance of low mass…

Instrumentation and Methods for Astrophysics · Physics 2015-06-17 Brendon J. Brewer , Philip J. Marshall , Matthew W. Auger , Tommaso Treu , Aaron A. Dutton , Matteo Barnabè

Extended, old, and round stellar halos appear to be ubiquitous around high-mass dwarf galaxies ($10^{8.5}<M_\star/M_\odot<10^{9.6}$) in the observed universe. However, it is unlikely that these dwarfs have undergone a sufficient number of…

Galaxies can form in a sufficiently deep gravitational potential so that efficient gas cooling occurs. We estimate that such potential is provided by a halo of mass $M \gtsim M_{c} \approx 7.0 \times 10^{12} ~ (\Delta_{c}(z)…

Astrophysics · Physics 2009-09-07 Hung-Yu Jian , Chia-Hung Chien , Tzihong Chiueh

Massive relic galaxies formed the bulk of their stellar component before z~2 and have remained unaltered since then. Therefore, they represent a unique opportunity to study in great detail the frozen stellar population properties of those…

There is mounting evidence that the stellar initial mass function (IMF) could extend much beyond the canonical Mi ~100, Msun limit, but the impact of such hypothesis on the chemical enrichment of galaxies still remains to be clarified. We…

Astrophysics of Galaxies · Physics 2021-06-30 S. Goswami , A. Slemer , P. Marigo , A. Bressan , L. Silva , M. Spera , L. Boco , V. Grisoni , L. Pantoni , A. Lapi

Accreted stellar populations are comprised of the remnants of destroyed galaxies, and often dominate the `stellar haloes' of galaxies such as the Milky Way (MW). This ensemble of external contributors is a key indicator of the past assembly…

Astrophysics of Galaxies · Physics 2023-03-01 Alis J. Deason , Sergey E. Koposov , Azadeh Fattahi , Robert J. J. Grand

Dwarf galaxies have a wide variety of structures, such as dark matter (DM) distribution, stellar-to-halo mass ratio, and stellar density. Recent high-resolution simulations have shown a variety of stellar-to-halo mass ratios for dwarf…

Astrophysics of Galaxies · Physics 2026-01-21 Katsuhiro Kaneko , Takayuki R. Saitoh , Yutaka Hirai , Michiko S. Fujii

Deep optical/near-IR surface photometry of galaxies outside the Local Group have revealed faint and very red halos around objects as diverse as disk galaxies and starbursting dwarf galaxies. The colours of these structures are too extreme…

Astrophysics · Physics 2009-11-13 E. Zackrisson , N. Bergvall , C. Flynn , G. Ostlin , G. Micheva , B. Caldwell

The chemical evolution of the Galactic bulge is treated here in the context of an inside-out model for the Galaxy formation. We assume that this central region evolved even faster than the Galactic halo and test the effect of changing the…

Astrophysics · Physics 2007-05-23 F. Matteucci , D. Romano , P. Molaro

Context: The determination of the stellar initial mass function (IMF) of massive galaxies is one of the open problems in cosmology. Strong gravitational lensing is one of the few methods that allow us to constrain the IMF outside of the…

We exploit the recent observations of extremely metal-poor (EMP) stars in the Galactic halo and investigate the constraints on the IMF of the stellar population that left these low-mass survivors of [Fe/H]<-2.5 and the chemical evolution…

Astrophysics of Galaxies · Physics 2011-02-11 Yutaka Komiya , Takuma Suda , Masayuki Y. Fujimoto

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…

Astrophysics of Galaxies · Physics 2018-03-14 Giulio Rosani , Anna Pasquali , Francesco La Barbera , Ignacio Ferreras , Alexandre Vazdekis

White Dwarfs (WDs) are the final evolutionary product of the vast majority of stars in the Universe. They are electron-degenerate structures characterized by no stable thermonuclear activity, and their evolution is generally described as a…

Astrophysics of Galaxies · Physics 2021-09-07 J. Chen , F. R. Ferraro , M. Cadelano , M. Salaris , B. Lanzoni , C. Pallanca , L. G. Althaus , E. Dalessandro , -

The stellar initial mass function (IMF) describes the distribution in stellar masses produced from a burst of star formation. For more than fifty years, the implicit assumption underpinning most areas of research involving the IMF has been…