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Related papers: The pulsational properties of ultra-massive DB whi…

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Pulsating low-mass white dwarf stars are white dwarfs with stellar masses between 0.30~M$_{\odot}$ and 0.45~M$_{\odot}$ that show photometric variability due to gravity-mode pulsations. Within this mass range, they can harbour both a…

Solar and Stellar Astrophysics · Physics 2021-12-15 A. D. Romero , G. R. Lauffer , A. G. Istrate , S. G. Parsons

Galactic history is written in the white dwarf stars. Their surface properties hint at interiors composed of matter under extreme conditions. In the forty years since their discovery, pulsating white dwarf stars have moved from side-show…

Astrophysics · Physics 2009-11-13 D. E. Winget , S. O. Kepler

ZZ Ceti stars are pulsating white dwarfs with a carbon-oxygen core (or possibly ONe for the most massive stars) build up during the core helium burning (CHeB) and thermally pulsing Asymptotic Giant Branch (TP-AGB) phases. Through the…

Solar and Stellar Astrophysics · Physics 2018-09-26 F. C. De Gerónimo , L. G. Althaus , A. H. Córsico , A. D. Romero , S. O. Kepler

White dwarfs, the final evolutionary stage of the vast majority of stars, serve as critical tools for cosmochronology, studies of planetary system evolution, and laboratories for non-standard physics, including exotic cooling channels and…

Instrumentation and Methods for Astrophysics · Physics 2025-12-19 Murat Uzundag , Ingrid Pelisoli , Stephane Charpinet , Alejandro H. Corsico , Leandro G. Althaus , V. Van Grootel , Suzanna Randall , Thomas Kupfer , Roberto Raddi

Hot DQ white dwarfs constitute a new class of white dwarf stars, uncovered recently within the framework of the SDSS project. Recently, three hot DQ white dwarfs have been reported to exhibit photometric variability with periods compatible…

Solar and Stellar Astrophysics · Physics 2015-05-13 A. H. Córsico , A. D. Romero , L. G. Althaus , E. García-Berro

We study the structure and evolution of white dwarf stars with helium-rich atmospheres (DB) in a self-consistent way with the predictions of time-dependent element diffusion. Our treatment of diffusion includes gravitational settling and…

Astrophysics · Physics 2009-11-10 L. G. Althaus , A. H. Corsico

White dwarf stars are the most common end point of stellar evolution. Of special interest are the ultramassive white dwarfs, as they are related to type Ia Supernovae explosions, merger events, and Fast Radio Bursts. Ultramassive white…

Ultra-massive hydrogen-rich (DA spectral type) white dwarf (WD) stars ($M_{\star} > 1M_{\odot}$) coming from single-star evolution are expected to harbor cores made of $^{16}$O and $^{20}$Ne, resulting from semi-degenerate carbon burning…

Solar and Stellar Astrophysics · Physics 2020-11-24 A. H. Córsico , F. C. De Gerónimo , M. E. Camisassa , L. G. Althaus

At present, a large number of pulsating white dwarf (WD) stars is being discovered either from Earth-based surveys such as the Sloan Digital Sky Survey, or through observations from space (e.g., the Kepler mission). The asteroseismological…

Solar and Stellar Astrophysics · Physics 2017-03-06 Alejandro H. Córsico

Motivated by the recent detection of single and binary He-core white dwarfs in metal-rich clusters, we present a full set of evolutionary calculations and colors appropriate for the study of such white dwarfs. The paper is also aimed at…

Solar and Stellar Astrophysics · Physics 2015-05-13 L. G. Althaus , J. A. Panei , A. D. Romero , R. D. Rohrmann , A. H. Córsico , E. García-Berro , M. M. Miller Bertolami

The recent plethora of sky surveys, especially the Sloan Digital Sky Survey, have discovered many low-mass (M < 0.45 Msun) white dwarfs that should have cores made of nearly pure helium. These WDs come in two varieties; those with masses…

Two of the possibilities for the formation of low-mass ($M_{\star}\lesssim 0.5\,M_{\odot}$) hydrogen-deficient white dwarfs are the occurrence of a very-late thermal pulse after the asymptotic giant-branch phase or a late helium-flash onset…

Solar and Stellar Astrophysics · Physics 2020-07-01 Tiara Battich , Leandro G. Althaus , Alejandro H. Córsico

A recent study by Yoon & Langer (2004a) indicated that the inner cores of rapidly accreting (Mdot > 10^{-7} M_sun/yr) CO white dwarfs may rotate differentially, with a shear rate near the threshold value for the onset of the dynamical shear…

Astrophysics · Physics 2008-11-26 Sung-Chul Yoon , Norbert Langer

We present a prescription for parametrizing the chemical profile in the core of white dwarfs in the light of the recent discovery that pulsation modes may sometimes be deeply confined in some cool pulsating white dwarfs. Such modes may be…

Solar and Stellar Astrophysics · Physics 2017-01-18 N. Giammichele , S. Charpinet , G. Fontaine , P. Brassard

We present a new method that investigates the evolutionary history of the pulsating DB white dwarf GD358 using asteroseismology. This is done considering the internal C/O profile, which describes the relative abundances of carbon and oxygen…

Astrophysics · Physics 2008-02-15 J. M. Gonzalez Perez , T. S. Metcalfe

White dwarf asteroseismology offers the opportunity to probe the structure and composition of stellar objects governed by relatively simple physical principles. The observational requirements of asteroseismology have been addressed by the…

Astrophysics · Physics 2009-11-06 Travis S. Metcalfe

Helium core white dwarfs (WDs) with mass M <~ 0.20 Msun undergo several Gyrs of stable hydrogen burning as they evolve. We show that in a certain range of WD and hydrogen envelope masses, these WDs may exhibit g-mode pulsations similar to…

Solar and Stellar Astrophysics · Physics 2015-05-19 Justin D. R. Steinfadt , Lars Bildsten , Phil Arras

In the absence of a third dredge-up episode during the asymptotic giant branch phase, white dwarf models evolved from low-metallicity progenitors have a thick hydrogen envelope, which makes hydrogen shell burning be the most important…

Solar and Stellar Astrophysics · Physics 2016-10-26 María E. Camisassa , Alejandro H. Córsico , Leandro G. Althaus , Hiromoto Shibahashi

Most of low- and intermediate-mass stars that populate the Universe will end their lives as white dwarf stars. These ancient stellar remnants have encrypted inside a precious record of the evolutionary history of the progenitor stars,…

Solar and Stellar Astrophysics · Physics 2014-12-23 A. H. Córsico