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Related papers: White dwarf constraints on a varying $G$

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Ultra-massive white dwarfs are powerful tools to study various physical processes in the Asymptotic Giant Branch (AGB), type Ia supernova explosions and the theory of crystallization through white dwarf asteroseismology. Despite the…

Massive, highly magnetized white dwarfs with fields up to $10^9$ G have been observed and theoretically used for the description of a variety of astrophysical phenomena. Ultramagnetized white dwarfs with uniform interior fields up to…

Solar and Stellar Astrophysics · Physics 2014-09-29 J. G. Coelho , R. M. Marinho , M. Malheiro , R. Negreiros , D. L. Cáceres , J. A. Rueda , R. Ruffini

Only a handful of gas giant planets orbiting white dwarfs are known. It remains unclear whether this paucity reflects observational challenges or the consequences of stellar evolution. We aim to carry out population synthesis of substellar…

Analysis of AR Sco optical light curves spanning nine years show a secular change in the relative amplitudes of the beat pulse pairs generated by the two magnetic poles of its rotating white dwarf. Recent photometry now shows that the…

Deriving precise stellar ages is a challenging task. Consequently, age-dependent relations - such as the age-metallicity and age-velocity dispersion relations of the Milky Way, or the age-rotation-activity relation of low-mass stars - are…

We consider the pulsational properties of white dwarf star models with temperatures appropriate for the ZZ Ceti instability strip and with masses large enough that they should be substantially crystallized. Our work is motivated by the…

Astrophysics · Physics 2009-10-31 M. H. Montgomery , D. E. Winget

The evolution of star clusters is studied using N-body simulations in which the evolution of single stars and binaries are taken self-consistently into account. Initial conditions are chosen to represent relatively young Galactic open…

M dwarfs remain active over longer timescales than their Sunlike counterparts, with potentially devastating implications for the atmospheres of their planets. However, the age at which fully-convective M dwarfs transition from active and…

Solar and Stellar Astrophysics · Physics 2022-09-14 Emily K. Pass , David Charbonneau , Jonathan M. Irwin , Jennifer G. Winters

The standard theory of pulsations deals with the frequencies and growth rates of infinitesimal perturbations in a stellar model. Modes which are calculated to be linearly driven should increase their amplitudes exponentially with time; the…

Solar and Stellar Astrophysics · Physics 2020-02-19 M. H. Montgomery , J. J. Hermes , D. E. Winget , B. H. Dunlap , K. J. Bell

White dwarfs (WDs) represent the final evolutionary stage of most stars, typically originating from progenitor stars with masses below approximately 8 $M_{\odot}$ to 10 $M_{\odot}$. Formation through single-star evolution generally requires…

We present here a detailed pulsational study applied to low-mass He-core white dwarfs, based on full evolutionary models representative of these objects. The background stellar models on which our pulsational analysis was carried out were…

Solar and Stellar Astrophysics · Physics 2015-06-11 A. H. Córsico , A. D. Romero , L. G. Althaus , J. J. Hermes

Using the most recent results about white dwarfs in 10 open clusters, we revisit semi-empirical estimates of the initial-final mass relation in star clusters, with emphasis on the use of stellar evolution models. We discuss the influence of…

Astrophysics · Physics 2011-02-11 Maurizio Salaris , Aldo Serenelli , Achim Weiss , Marcelo Miller Bertolami

Many magnetic white dwarfs exhibit a polarised spectrum that periodically varies as the star rotates because the magnetic field is not symmetric about the rotation axis. In this work, we report the discovery that while weakly magnetic white…

Solar and Stellar Astrophysics · Physics 2024-11-18 S. Bagnulo , J. D. Landstreet

We present new white dwarf evolutionary sequences for low-metallicity progenitors. White dwarf sequences have been derived from full evolutionary calculations that take into account the entire history of progenitor stars, including the…

Over the last decade or so, we have been developing the possible existence of highly magnetized white dwarfs with analytical stellar structure models. While the primary aim was to explain the nature of the peculiar overluminous type Ia…

High Energy Astrophysical Phenomena · Physics 2021-11-01 B. Mukhopadhyay , M. Bhattacharya , A. J. Hackett , S. Kalita , D. Karinkuzhi , C. A. Tout

Recent observations of white dwarfs in globular clusters indicate that these stars may get a velocity kick during their time as giants. This velocity kick could originate naturally if the mass loss while on the asymptotic giant branch is…

Astrophysics · Physics 2009-11-13 Jeremy S. Heyl

We explore the internal structures of the white dwarfs in two different modified theories of gravity: (i) scalar-tensor-vector gravity and (ii) beyond Horndeski theories of $G_3$ type. The modification of the gravitational force inside the…

General Relativity and Quantum Cosmology · Physics 2023-01-31 Khursid Alam , Tousif Islam

A number of White Dwarfs (WDs) in cataclysmic binaries have shown brightness variations consistent with non-radial oscillations as observed in isolated WDs. A few objects have been well-characterized with photometric campaigns in the hopes…

Solar and Stellar Astrophysics · Physics 2016-01-12 Dean M. Townsley , Phil Arras , Lars Bildsten

We discuss the feasibility of using astrophysical observations of white dwarfs as probes of fundamental physics. We quantify the effects of varying fundamental couplings on the white dwarf mass-radius relation in a broad class of…

Cosmology and Nongalactic Astrophysics · Physics 2017-10-17 D. M. N. Magano , J. M. A. Vilas Boas , C. J. A. P. Martins

We study the dynamical evolution of globular clusters containing primordial binaries, including full single and binary stellar evolution using our Monte Carlo cluster evolution code updated with an adaptation of the single and binary…

Astrophysics of Galaxies · Physics 2014-11-20 Sourav Chatterjee , John M. Fregeau , Stefan Umbreit , Frederic A. Rasio
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