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Related papers: White dwarf cooling in $f(R,T)$ gravity

200 papers

The discovery of the existence of an upper bound on the mass of a white dwarf star is considered as one of the finest of twentieth century astrophysics. On approaching this limiting mass of $1.4M_\odot$, known as the Chandrasekhar…

General Relativity and Quantum Cosmology · Physics 2019-08-30 Sayan K Pal , Partha Nandi

A detailed analysis of halo white dwarf candidates is presented, which is based on model atmosphere fits to observed energy distributions built from photoelectric or photographic magnitudes. Most of the candidates identified in reduced…

Astrophysics · Physics 2009-11-07 P. Bergeron

In Palatini $f(R)$ gravity, the parameters of the Schwarzschild - de Sitter solution as well as the whole interior solutions of compact objects are expected to change when compared to general relativity. We solve the Palatini field…

General Relativity and Quantum Cosmology · Physics 2009-12-07 Vappu Reijonen

Recently, the power of Gaia data has revealed an enhancement of high-mass white dwarfs (WDs) on the Hertzsprung--Russell diagram, called the Q branch. This branch is located at the high-mass end of the recently identified crystallization…

Solar and Stellar Astrophysics · Physics 2019-12-12 Sihao Cheng , Jeffrey D. Cummings , Brice Ménard

In this work, we investigate the equilibrium configurations of massive white dwarfs (MWD) in the context of modified gravity, namely $f(R,L_m)$ gravity, where $R$ stands for the Ricci scalar and $L_m$ is the Lagrangian matter density. We…

General Relativity and Quantum Cosmology · Physics 2022-06-22 R. V. Lobato , G. A. Carvalho , N. G. Kelkar , M. Nowakowski

We present a large forward-modeling analysis for 55 late-T (T7-T9) dwarfs, using low-resolution ($R\approx150$) near-infrared spectra and cloudless Sonora-Bobcat model atmospheres. We derive the objects' effective temperatures, surface…

Solar and Stellar Astrophysics · Physics 2021-11-17 Zhoujian Zhang , Michael C. Liu , Mark S. Marley , Michael R. Line , William M. J. Best

The precise astrometric measurements of the Gaia Data Release 2 have opened the door to detailed tests of the predictions of white dwarf cooling models. Significant discrepancies between theory and observations have been identified, the…

Solar and Stellar Astrophysics · Physics 2021-04-21 Simon Blouin , Jerome Daligault , Didier Saumon

Chandrasekhar made the startling discovery about nine decades back that the mass of compact object white dwarf has a limiting value, once nuclear fusion reactions stop therein. This is the Chandrasekhar mass-limit, which is $\sim1.4M_\odot$…

General Relativity and Quantum Cosmology · Physics 2021-04-27 Surajit Kalita , Banibrata Mukhopadhyay , T. R. Govindarajan

Accurate models of cooling white dwarfs must treat the energy released as their cores crystallize. This phase transition slows the cooling by releasing latent heat and also gravitational energy, which results from phase separation: liquid C…

Solar and Stellar Astrophysics · Physics 2023-12-20 M. H. Montgomery , Bart H. Dunlap

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

The explosion of a type Ia supernova starts in a white dwarf as a laminar deflagration at the center of the star and soon several hydrodynamic instabilities, in particular, the Rayleigh-Taylor instability, begin to act. A cellular…

We present an empirical determination of the white dwarf cooling sequence in the globular cluster 47 Tucanae. Using spectral models, we determine temperatures for 887 objects from Wide Field Camera 3 data, as well as 292 objects from data…

Solar and Stellar Astrophysics · Physics 2015-06-11 R. Goldsbury , J. Heyl , H. B. Richer , P. Bergeron , A. Dotter , J. S. Kalirai , J. MacDonald , R. M. Rich , P. B. Stetson , P. -E. Tremblay , K. A. Woodley

Double white dwarf (WD) binaries are increasingly being discovered at short orbital periods where strong tidal effects and significant tidal heating signatures may occur. We assume the tidal potential of the companion excites outgoing…

Solar and Stellar Astrophysics · Physics 2024-03-28 Peter Scherbak , Jim Fuller

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

We present a new model for the Galactic population of close double white dwarfs. The model accounts for the suggestion of the avoidance of a substantial spiral-in during mass transfer between a giant and a main-sequence star of comparable…

Astrophysics · Physics 2015-05-20 Lev Yungelson , Gijs Nelemans , Simon. F. Portegies Zwart , Frank Verbunt

As a result of competing physical mechanisms, the atmospheric composition of white dwarfs changes throughout their evolution, a process known as spectral evolution. Because of the ambiguity of their atmospheric compositions and the…

Solar and Stellar Astrophysics · Physics 2019-06-19 Simon Blouin , Patrick Dufour , Christian Thibeault , Nicole F. Allard

We present full evolutionary calculations appropriate for the study of hydrogen-rich DA white dwarfs. This is done by evolving white dwarf progenitors from the zero age main sequence, through the core hydrogen burning phase, the helium…

We use the most recent, complete and independent measurements of masses and radii of white dwarfs in binaries to bound the class of non-trivial modified gravity theories, viable after GW170817/GRB170817, using its effect on the mass-radius…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-23 Ippocratis D. Saltas , Ignacy Sawicki , Ilidio Lopes

Models predict that the well-studied mass-radius relation of white dwarf stars depends on the temperature of the star, with hotter white dwarfs having larger masses at a given radius than cooler stars. In this paper, we use a catalog of…

Is the Chandrasekhar mass limit for white dwarfs (WDs) set in stone? Not anymore -- recent observations of over-luminous, peculiar type Ia supernovae can be explained if significantly super-Chandrasekhar WDs exist as their progenitors, thus…

High Energy Astrophysical Phenomena · Physics 2013-09-19 Upasana Das , Banibrata Mukhopadhyay