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Related papers: Simulating a white dwarf dominated halo

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Aims: We study single and binary white dwarfs in the inner halo of the Milky Way in order to learn more about the conditions under which the population of halo stars was born, such as the initial mass function (IMF), the star formation…

The interpretation of microlensing results towards the Large Magellanic Cloud (LMC) still remains controversial. White dwarfs have been proposed to explain these results and, hence, to contribute significantly to the mass budget of our…

Astrophysics · Physics 2009-11-13 J. Camacho , S. Torres , J. Isern , L. G. Althaus , E. Garcia-Berro

I discuss two hypotheses that might explain LMC microlensing: the Halo stellar remnant lensing hypothesis and the unvirialized LMC lensing hypothesis. I show that white dwarfs cannot contribute substantially to the cosmic baryon budget;…

Astrophysics · Physics 2007-05-23 David S. Graff

We review recent advances in our understanding of the origin of the initial mass function (IMF). We emphasize the use of numerical simulations to investigate how each physical process involved in star formation affects the resulting IMF. We…

Astrophysics · Physics 2007-05-23 Ian A. Bonnell , Richard B. Larson , Hans Zinnecker

The discovery of Massive Astrophysical Compact Halo Objects (MACHOs) in microlensing experiments makes it compelling to understand their physical nature, as well as their formation mechanism. Within the present uncertainties, brown dwarfs…

Astrophysics · Physics 2011-05-12 F. De Paolis , G. Ingrosso , Ph. Jetzer , M. Roncadelli

The manner in which the stellar initial mass function (IMF) scales with global galaxy properties is under debate. We use two hydrodynamical, cosmological simulations to predict possible trends for two self-consistent variable IMF…

Astrophysics of Galaxies · Physics 2018-10-22 Christopher Barber , Joop Schaye , Robert A. Crain

Motivated by the observed bottom-light initial mass function (IMF) in faint dwarfs, we study how a metallicity-dependent IMF affects the feedback budget and observables of an ultra-faint dwarf galaxy. We model the evolution of a low-mass…

We present high-resolution simulations of tidal dwarf galaxies (TDG) to investigate their early chemo-dynamical evolution and test their survivability. In this work the simulation setup is introduced and the response of TDGs to…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 S. Ploeckinger , G. Hensler , S. Recchi , N. Mitchell , P. Kroupa

We revisit the properties and astrophysical implications of the field white dwarf mass distribution in preparation of Gaia applications. Our study is based on the two samples with the best established completeness and most precise…

Solar and Stellar Astrophysics · Physics 2016-07-27 P. -E. Tremblay , J. Cummings , J. S. Kalirai , B. T. Gaensicke , N. Gentile-Fusillo , R. Raddi

We use recent microlensing observations toward the central bulge of the Galaxy to probe the overall stellar plus brown dwarf initial mass function (IMF) in these regions well within the brown dwarf domain. We find that the IMF is consistent…

Astrophysics of Galaxies · Physics 2023-02-22 Gilles Chabrier , Romain Lenoble

Recent observational and theoretical studies indicate that the stellar initial mass function (IMF) varies systematically with the environment (star formation rate - SFR, metallicity). Although the exact dependence of the IMF on those…

Astrophysics of Galaxies · Physics 2020-04-08 Martyna Chruslinska , Tereza Jerabkova , Gijs Nelemans , Zhiqiang Yan

The first generations of stars ionised and enriched their host galaxies and seeded the growth of massive black holes. Models often assume that Pop III stellar masses in different minihaloes are stochastic realisations of a single universal…

Astrophysics of Galaxies · Physics 2026-04-06 Shingo Hirano , Yusuke Sakai , Hideyuki Umeda

We examine the applicability of the initial-to-final mass relation (IFMR) for white dwarfs (WDs) in intermediate-separation binary systems (approximately 1 AU), using astrometric binaries identified in open clusters from Gaia DR3. A careful…

Solar and Stellar Astrophysics · Physics 2025-01-30 Oren Ironi , Sagi Ben-Ami , Na'ama Hallakoun , Sahar Shahaf

Ultra-massive white dwarfs ($\rm M_{WD} \gtrsim 1.05\, M_{\odot}$) are considered powerful tools to study type Ia supernovae explosions, merger events, the occurrence of physical processes in the Super Asymptotic Giant Branch (SAGB) phase,…

Solar and Stellar Astrophysics · Physics 2022-03-09 María E. Camisassa , Leandro G. Althaus , Detlev Koester , Santiago Torres , Pilar Gil Pons , Alejandro H. Córsico

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

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

The mass function of hydrogen-rich atmosphere white dwarfs has been frequently found to reveal a distinctive high-mass excess near 1Msun. However, a significant excess of massive white dwarfs has not been detected in the mass function of…

Solar and Stellar Astrophysics · Physics 2015-08-06 A. Rebassa-Mansergas , M. Rybicka , X. -W. Liu , Z. Han , E. Garcia-Berro

Observations by the MACHO collaboration indicate that a significant fraction of the galactic halo dark matter may be in form of compact objects with masses $M\sim 0.5M_{\odot}$. Identification of these objects as red or white dwarfs is…

Astrophysics · Physics 2009-10-30 Karsten Jedamzik

Extreme mass ratio inspirals (EMRIs) of low-mass white dwarfs (WDs, 0.1 - 0.3 Msun) around spinning intermediate-mass black holes (IMBHs, 10^3 - 10^5 Msun) offer unique opportunities for multi-messenger astronomy, emitting both…

High Energy Astrophysical Phenomena · Physics 2025-11-11 Yang Yang , Jie Yang , Xian Chen , Zihan Zhang

We study the Initial Mass Function (IMF) and host halo properties of Intermediate Mass Black Holes (IMBH, 10^{4-6} Msun) formed inside metal-free, UV illuminated atomic cooling haloes (virial temperature T_vir > 10^4 K) either via the…

Astrophysics of Galaxies · Physics 2015-06-22 A. Ferrara , S. Salvadori , B. Yue , D. R. G. Schleicher