English
Related papers

Related papers: Analysis of DQZ White Dwarf Evolution through Proc…

200 papers

Context. Understanding the survival and orbital evolution of brown dwarf (BD) companions during the post-main-sequence (MS) evolution of their host stars is increasingly important, especially with recent discoveries of many substellar…

Solar and Stellar Astrophysics · Physics 2026-03-19 Zhangliang Chen , Hongming Jin , Hongwei Ge , Cong Yu , Kejun Wang , Dichang Chen , Bo Ma

We present a theoretical description of macroscopic diffusion caused by convective overshoot in pure-hydrogen DA white dwarfs using three-dimensional (3D), closed-bottom, radiation hydrodynamics CO$^5$BOLD simulations. We rely on a new grid…

Solar and Stellar Astrophysics · Physics 2019-07-10 Tim Cunningham , Pier-Emmanuel Tremblay , Bernd Freytag , Hans-Günther Ludwig , Detlev Koester

The Peccei-Quinn mechanism proposed to solve the CP problem of Quantum Chromodynamics has as consequence the existence of axions, hypothetical weakly interacting particles whose mass is constrained to be on the sub-eV range. If these…

Solar and Stellar Astrophysics · Physics 2016-09-07 Tiara Battich , Alejandro Hugo Córsico , Leandro Gabriel Althaus , Marcelo Miguel Miller Bertolami

Accreting, nuclear-burning white dwarfs have been deemed to be candidate progenitors of type Ia supernovae, and to account for supersoft X-ray sources, novae, etc. depending on their accretion rates. We have carried out a binary population…

Solar and Stellar Astrophysics · Physics 2015-06-19 Hai-Liang Chen , T. E. Woods , L. R. Yungelson , M. Gilfanov , Zhanwen Han

We continue our comprehensive theoretical investigation of the spectral evolution of white dwarfs based on sophisticated simulations of element transport. In this paper, we focus on the transformation of PG 1159 stars into DO/DB white…

Solar and Stellar Astrophysics · Physics 2022-05-11 A. Bédard , P. Bergeron , P. Brassard

We describe radial velocity observations of a large sample of apparently single white dwarfs (WDs), obtained in a long-term effort to discover close, double-degenerate (DD) pairs which might comprise viable Type Ia Supernova (SN Ia)…

Astrophysics · Physics 2009-10-30 Rex A. Saffer , Mario Livio , Lev R. Yungelson

The present work is designed to explore the evolutionary and pulsational properties of low-mass white dwarfs with carbon/oxygen cores. In particular, we follow the evolution of a 0.33 Msun white dwarf remnant in a self-consistent way with…

Astrophysics · Physics 2009-11-10 L. G. Althaus , A. H. Corsico , A. Gautschy , Z. Han , A. M. Serenelli , J. A. Panei

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

Cool white dwarfs are reliable and independent stellar chronometers. The most common white dwarfs have carbon-oxygen dense cores. Consequently, the cooling ages of very cool white dwarfs sensitively depend on the adopted phase diagram of…

Solar and Stellar Astrophysics · Physics 2015-05-30 Leandro G. Althaus , Enrique García-Berro , Jordi Isern , Alejandro H. Córsico , Marcelo M. Miller Bertolami

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…

A photometric and spectroscopic analysis of 152 cool white dwarf stars is presented. The discovery of 7 new DA white dwarfs, 2 new DQ white dwarfs, 1 new magnetic white dwarf, and 3 weak magnetic white dwarf candidates, is reported, as well…

Astrophysics · Physics 2009-10-31 P. Bergeron , S. K. Leggett , Maria Teresa Ruiz

White dwarfs with metal-polluted atmospheres have been studied widely in the context of the accretion of rocky debris from evolved planetary systems. One open question is the geometry of accretion and how material arrives and mixes in the…

Motivated by the possibility that the fundamental ``constants'' of nature could vary with time, this paper considers the long term evolution of white dwarf stars under the combined action of proton decay and variations in the gravitational…

Astrophysics · Physics 2009-11-13 Jacob A. Ketchum , Fred C. Adams

We present a detailed spectroscopic and photometric analysis of 219 DA and DB white dwarfs for which trigonometric parallax measurements are available. Our aim is to compare the physical parameters derived from the spectroscopic and…

Solar and Stellar Astrophysics · Physics 2017-10-18 Antoine Bédard , Pierre Bergeron , Gilles Fontaine

We report on a search for differential shifts between electronic and vibronic transitions in carbon-rich white dwarfs BPM 27606 and Procyon B. The absence of differential shifts within the spectral resolution and taking into account…

High Energy Physics - Phenomenology · Physics 2014-10-01 Roberto Onofrio , Gary A. Wegner

We present a homogeneous analysis of 1023 DBZ/DZ(A) and 319 DQ white dwarf stars taken from the Montreal White Dwarf Database. This represents a significant increase over the previous comprehensive studies on these types of objects. We use…

Solar and Stellar Astrophysics · Physics 2020-01-08 S. Coutu , P. Dufour , P. Bergeron , S. Blouin , E. Loranger , N. F. Allard , B. H Dunlap

The study of high contrast imaged brown dwarfs and exoplanets depends strongly on evolutionary models. To estimate the mass of a directly imaged substellar object, its extracted photometry or spectrum is used and adjusted with model spectra…

The initial-final mass relation (IFMR) represents the total mass lost by a star during the entirety of its evolution from the zero age main sequence to the white dwarf cooling track. The semi-empirical IFMR is largely based on observations…

Solar and Stellar Astrophysics · Physics 2021-09-28 Joseph W. Barnett , Kurtis A. Williams , A. Bédard , Michael Bolte

We present a systematic study of the physical properties of late-M dwarfs based on high-quality dynamical mass measurements and near-infrared (NIR) spectra. We use astrometry from Keck NGS and LGS AO imaging to determine orbits for late-M…

Solar and Stellar Astrophysics · Physics 2015-05-19 Trent Dupuy , Michael Liu , Brendan Bowler , Michael Cushing , Christiane Helling , Soeren Witte , Peter Hauschildt

We present follow-up spectroscopy and a detailed model atmosphere analysis of 29 wide double white dwarfs, including eight systems with a crystallized C/O core member. We use state-of-the-art evolutionary models to constrain the physical…

Solar and Stellar Astrophysics · Physics 2024-10-10 Manuel Barrientos , Mukremin Kilic , Pierre Bergeron , Simon Blouin , Warren R. Brown , Jeff J. Andrews