English
Related papers

Related papers: Evolutionary sequences for hydrogen-deficient whit…

200 papers

Observations of galactic white dwarfs with Gaia have allowed for unprecedented modeling of white dwarf cooling, resolving core crystallization and sedimentary heating from neutron rich nuclei. These cooling sequences are sensitive to the…

Solar and Stellar Astrophysics · Physics 2021-07-07 M. E. Caplan , I. F. Freeman

We have detected three new hydrogen-deficient (H < 0.001 mass fraction) pre-white dwarfs (WDs) with helium-dominated atmospheres. The first object is a relatively cool PG1159 star (effective temperature Teff = 72,000 K) that has the lowest…

Solar and Stellar Astrophysics · Physics 2024-12-23 Klaus Werner , Nicole Reindl , Max Pritzkuleit , Stephan Geier

We study the thermodynamics of helium at densities relevant for white dwarf physics. We find evidence that, as the temperature is increased, there is first a first order transition between two superconducting phases followed by a second…

High Energy Astrophysical Phenomena · Physics 2014-02-26 Paulo F. Bedaque , Evan Berkowitz , Srimoyee Sen

Recent Hubble Space Telescope observations have unveiled the white dwarf cooling sequence of the Galactic bulge. Although the degenerate sequence can be well fitted employing the most up-to-date theoretical cooling sequences, observations…

Astrophysics of Galaxies · Physics 2018-02-21 S. Torres , E. García-Berro , R. Cojocaru , A. Calamida

We perform binary evolution calculations on helium star - carbon-oxygen white dwarf (CO WD) binaries using the stellar evolution code MESA. This single degenerate channel may contribute significantly to thermonuclear supernovae at short…

Solar and Stellar Astrophysics · Physics 2019-06-26 Tin Long Sunny Wong , Josiah Schwab

We investigate in detail the white dwarf cooling sequence of the globular cluster Messier 4. In particular we study the influence of various systematic uncertainties, both observational and theoretical, on the determination of the cluster…

Pulsating white dwarfs provide constraints to the evolution of progenitor stars. We revise He-burning stellar models, with particular attention to core convection and to its connection with the nuclear reactions powering energy generation…

Astrophysics · Physics 2009-11-07 Oscar Straniero , Inma Dominguez , Gianluca Imbriani , Luciano Piersanti

The evolution of binaries consisting of evolved main sequence stars (1 < M_d/Msun < 3.5) with white dwarf companions (0.7 < M_wd/Msun < 1.2) is investigated through the thermal mass transfer phase. Taking into account the stabilizing effect…

Astrophysics · Physics 2016-08-30 Natalia Ivanova , Ronald E. Taam

White dwarf atmospheres are frequently polluted by material from their own planetary systems. Absorption features from Ca, Mg, Fe and other elements can provide unique insights into the provenance of this exoplanetary material, with their…

Earth and Planetary Astrophysics · Physics 2024-07-02 Andrew M. Buchan , Amy Bonsor , Laura K. Rogers , Marc G. Brouwers , Oliver Shorttle , Pier-Emmanuel Tremblay

White dwarfs are almost completely degenerate objects that cannot obtain energy from the thermonuclear sources and their evolution is just a gravothermal process of cooling. The simplicity of these objects, the fact that the physical inputs…

Solar and Stellar Astrophysics · Physics 2010-10-27 J. Isern , S. Catalan , E. Garcia-Berro , M. Salaris , S. Torres

We report the identification of the double degenerate system NLTT 16249 that comprises a normal, hydrogen-rich (DA) white dwarf and a peculiar, carbon-polluted white dwarf (DQ) showing photospheric traces of nitrogen. We disentangled the…

Solar and Stellar Astrophysics · Physics 2015-06-03 S. Vennes , A. Kawka

Isolated hot subdwarfs might be formed by the merging of two helium-core white dwarfs. Before merging, helium-core white dwarfs have hydrogen-rich envelopes and some of this hydrogen may survive the merger. We calculate the mass of hydrogen…

Solar and Stellar Astrophysics · Physics 2016-09-30 Philip D. Hall , C. Simon Jeffery

Low mass white dwarfs are the remnants of disrupted red giant stars in binary millisecond pulsars and other exotic binary star systems. Some low mass white dwarfs cool rapidly, while others stay bright for millions of years due to stable…

There is overwhelming evidence that white dwarfs host planetary systems; revealed by the presence, disruption, and accretion of planetary bodies. A lower limit on the frequency of white dwarfs that host planetary material has been estimated…

Helium-core white dwarfs (He WDs) formed through common envelope (CE) evolution offer valuable insight into binary interaction channels and compact remnant formation. Their cooling rates critically impact both detectability and age…

Solar and Stellar Astrophysics · Physics 2025-07-23 Leandro G. Althaus , Leila M. Calcaferro , Alejandro H. Córsico , Warren R. Brown

We present evolutionary models for low mass stars and brown dwarfs ($m \le 1.2 \msol$) based on recent improvement of the theory: equation of state, atmosphere models, ... We concentrate on early evolutionary phases from the initial…

Astrophysics · Physics 2007-05-23 I. Baraffe , G. Chabrier , F. Allard , P. Hauschildt

Hydrogen-rich matter has been added to a CO white dwarf of initial mass 0.516 \msun at the rates $10^{-8}$ and $2\times 10^{-8}$ \msun \yrm1, and results are compared with those for a white dwarf of the same initial mass which accretes pure…

Astrophysics · Physics 2009-10-31 L. Piersanti , S. Cassisi , I. Iben , A. Tornambe'

We study the full evolution of a 1.313 Msun white dwarf star that descended from a 9 Msun main-sequence progenitor with an initial metallicity of Z=0.02. Using MESA r24.08.01, we calculate its entire evolution from pre-ZAMS to the WD…

Solar and Stellar Astrophysics · Physics 2026-03-12 Ana S. R. Antonini , Alejandra D. Romero , S. O. Kepler

An adiabatic, non-radial pulsation study of a 0.563 M_sun DA white dwarf model is presented on the basis of new evolutionary calculations performed in a self-consistent way with the predictions of time dependent element diffusion, nuclear…

Astrophysics · Physics 2009-11-07 A. H. Corsico , L. G. Althaus , O. G. Benvenuto , A. M. Serenelli

We investigate the formation of the ten double-lined double white dwarfs that have been observed so far. A detailed stellar evolution code is used to calculate grids of single-star and binary models and we use these to reconstruct possible…

Astrophysics · Physics 2007-05-23 M. V. van der Sluys , F. Verbunt , O. R. Pols
‹ Prev 1 8 9 10 Next ›