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Related papers: White dwarf cooling via gravity portals

200 papers

White dwarfs can be used as galactic chronometers and, therefore, provide important information about galactic evolution if good theoretical models of their cooling are available. Consequently, it is natural to wonder if all the sources or…

Astrophysics · Physics 2016-08-15 J. Isern , R. Mochkovitch , E. García--Berro , Margarita Hernanz

White dwarfs are compact objects that stand against gravitational collapse by their internal pressure of degenerate matter. In this work we aimed to perform an introductory study on these stars, using two equations of state (EOS): (I) an…

Solar and Stellar Astrophysics · Physics 2018-06-22 Sílvia Pereira Nunes , Marcelo Chiapparini , Santiago Esteban Perez Bergliaffa

White dwarfs are one of the densest form of matter following neutron star and black holes. A typical white dwarf is as massive as our sun has radius comparable to the earth. This paper reviewed the Fermi gas model Equation of State of white…

Solar and Stellar Astrophysics · Physics 2025-01-29 Tousif Raza

In this paper we compute detailed evolutionary models providing chemical profiles for white dwarfs having progenitors in the mass range from 1.0 to $7 M_{\sun}$ and we examine the influence of such profiles in the cooling process. The…

Astrophysics · Physics 2016-08-30 M. Salaris , I. Dominguez , E. Garcia-Berro , M. Hernanz , J. Isern , R. Mochkovitch

Sufficiently old white dwarfs cool down through a convective envelope that directly couples their degenerate cores to the surface. Magnetic fields may inhibit this convection by stiffening the criterion for convective instability. We…

Solar and Stellar Astrophysics · Physics 2024-09-13 Sivan Ginzburg

Motivated by the fact that, so far, the whole body of evidence for dark matter is of gravitational origin, we study the decays of dark matter into Standard Model particles mediated by gravity portals, i.e., through nonminimal gravitational…

High Energy Physics - Phenomenology · Physics 2017-03-14 Oscar Catà , Alejandro Ibarra , Sebastian Ingenhütt

We present an improved treatment for the scattering of heavy dark matter from the ion constituents of a white dwarf. In the heavy dark matter regime, multiple collisions are required for the dark matter to become gravitationally captured.…

High Energy Physics - Phenomenology · Physics 2024-07-22 Nicole F. Bell , Giorgio Busoni , Sandra Robles , Michael Virgato

The evolution of white dwarfs is a cooling process that depends on the energy stored in the core and on the way in which it is transferred through the envelope. In this paper we show that despite some (erroneous) claims, the redistribution…

Astrophysics · Physics 2009-10-31 J. Isern , E. Garcia-Berro , M. Hernanz , G. Chabrier

The evolution of white dwarfs is a simple gravothermal process. This means that their luminosity function, i.e. the number of white dwarfs per unit bolometric magnitude and unit volume as a function of bolometric magnitude, is a…

Astrophysics of Galaxies · Physics 2015-06-12 J. Isern , A. Artigas , E. Garcia-Berro

Recently, it has been shown by S.~M. de Carvalho et al. (2014) that the deviations between the degenerate case and observations were already evident for 0.7-0.8 M$_{\odot}$ white dwarfs. Such deviations were related to the neglected effects…

Solar and Stellar Astrophysics · Physics 2016-04-13 Kuantay Boshkayev , Jorge A. Rueda , Bakytzhan Zhami , Zhanerke Kalymova , Galymdin Balgymbekov

The evolution of white dwarfs (WDs) depends crucially on thermal processes. The plasma in their core can produce neutrinos which escape from the star, thus contributing to the energy loss. While in absence of a magnetic field the main…

Solar and Stellar Astrophysics · Physics 2022-08-02 Marco Drewes , Jamie McDonald , Loïc Sablon , Edoardo Vitagliano

We propose a novel and feasible method to detect dark matter (DM) electron interaction via pulsating white dwarfs (WDs) in the central region of globular clusters. Annihilation of the DM particles captured by those WDs can provide…

High Energy Astrophysical Phenomena · Physics 2017-03-30 Jia-Shu Niu , Weikai Zong , Hui-Fang Xue

We present the first radiation magnetohydrodynamics simulations of the atmosphere of white dwarf stars. We demonstrate that convective energy transfer is seriously impeded by magnetic fields when the plasma-beta parameter, the thermal to…

Solar and Stellar Astrophysics · Physics 2015-10-14 P. -E. Tremblay , G. Fontaine , B. Freytag , O. Steiner , H. -G. Ludwig , M. Steffen , S. Wedemeyer , P. Brassard

A number of so-called ultra-cool white dwarfs have been detected in different surveys so far. However, based on anecdotal evidence it is believed that most or all of these ultra-cool white dwarfs are low-mass products of binary evolution…

Astrophysics of Galaxies · Physics 2015-05-20 S. Catalan , R. Napiwotzki , S. Hodgkin , D. Pinfield , D. Cristobal Hornillos

To the best of our knowledge, there are no specific calculations of gravity-darkening exponents for white dwarfs in the literature. On the other hand, the number of known eclipsing binaries whose components are tidally and/or rotationally…

Solar and Stellar Astrophysics · Physics 2021-04-28 A. Claret

Reliable modeling of the atmospheres of cool white dwarfs is crucial for understanding the atmospheric evolution of these stars and for accurate white dwarfs cosmochronology. Over the last decade {\it ab initio} modeling entered many…

Solar and Stellar Astrophysics · Physics 2015-05-20 Piotr M. Kowalski

We report on photometric and spectroscopic observations of white dwarf companions to four binary radio millisecond pulsars, leading to the discovery of companions to PSRs J0614-3329, J1231-1411 and J2017+0603. We place limits on the…

High Energy Astrophysical Phenomena · Physics 2015-12-09 C. G. Bassa , J. Antoniadis , F. Camilo , I. Cognard , D. Koester , M. Kramer , S. R. Ransom , B. W. Stappers

We analysed the cooling of white dwarfs in the globular cluster 47 Tucanae using deep observations from the Hubble Space Telescope that resolve the white dwarf cooling sequence to late enough cooling times that the white dwarf core has…

Solar and Stellar Astrophysics · Physics 2025-07-30 Leesa Fleury , Harvey Richer , Jeremy Heyl

Due to the short settling times of metals in DA white dwarf atmospheres, any white dwarfs with photospheric metals must be actively accreting. It is therefore natural to expect that the metals may not be deposited uniformly on the surface…

Astrophysics · Physics 2009-11-13 M. H. Montgomery , S. E. Thompson , T. von Hippel

We consider a model where the interaction between dark matter and the Standard Model particles are mediated by a ghost-free bi-gravity portal. The bi-gravity model invokes a massive spin-2 particle coupled to the usual massless graviton as…

High Energy Physics - Phenomenology · Physics 2023-10-06 Qing Chen , Shuang-Yong Zhou