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Related papers: Cooling Process of White Dwarf Stars in Palatini $…

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A few questions related to white dwarfs' physics is posed. It seems that the modified gravity framework can be a good starting point to provide alternative explanations to cooling processes, their age determination, and Chandrasekhar mass…

General Relativity and Quantum Cosmology · Physics 2021-07-29 Aneta Wojnar

We analyze the effects of modified gravity on specific heats of electrons and ions, Debye temperature, crystallization process, and cooling mechanism in white dwarfs. We derive the Lane-Emden-Chandrasekhar equation and relate it to the…

General Relativity and Quantum Cosmology · Physics 2023-03-07 Surajit Kalita , Lupamudra Sarmah , Aneta Wojnar

In recent times, astounding observations of both over- and under-luminous type Ia supernovae have emerged. These peculiar observations hint not only at surpassing the Chandrasekhar limit but may also suggest potential modifications in the…

General Relativity and Quantum Cosmology · Physics 2024-05-16 Snehasish Bhattacharjee

We study the effects of massive scalar-tensor theories on the internal properties, crystallization, and cooling process of white dwarf stars that might potentially solve observational tensions. We show that these modified gravity theories…

General Relativity and Quantum Cosmology · Physics 2024-08-29 Sofía Vidal , Aneta Wojnar , Laur Järv , Daniela Doneva

We present an analytical model for the evolution of brown dwarfs in quadratic Palatini f(R) gravity. We improve previous studies by adopting a more realistic description of the partially-degenerate state that characterizes brown dwarfs.…

General Relativity and Quantum Cosmology · Physics 2021-03-24 María Benito , Aneta Wojnar

There are currently two open questions in white dwarf physics: why are massive dwarfs observed less often in astronomical surveys, and why have not any super-Chandrasekhar white dwarfs been found despite the discovery of more than a dozen…

Solar and Stellar Astrophysics · Physics 2024-02-13 Aneta Wojnar , Surajit Kalita , Lupamudra Sarmah

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

Recent observations of several peculiar over- and under-luminous type Ia supernovae infer indirect evidence for the violation of the Chandrasekhar mass-limit by suggesting the existence of super- and sub-Chandrasekhar limiting mass white…

General Relativity and Quantum Cosmology · Physics 2022-01-11 Lupamudra Sarmah , Surajit Kalita , Aneta Wojnar

We investigate the impact of gravity portal to properties of white dwarfs, such as equation-of-state as well as cooling time. We find that the interaction between dark matter spin-zero bosons and electrons in the mean field approximation…

High Energy Physics - Phenomenology · Physics 2020-02-05 Grigoris Panotopoulos , Ilídio Lopes

Cooling processes of brown dwarf stars and giant planets are studied in the framework of DHOST theories. We confirm the previous results in the field that the effect of modified gravity on substellar objects' age is pronounced the most.

General Relativity and Quantum Cosmology · Physics 2023-07-19 Aleksander Kozak , Kärt Soieva , Aneta Wojnar

We investigate the Chandrasekhar mass limit for white dwarfs in various models of $f(R)$ gravity. Two equations of state for stellar matter are used: simple relativistic polytropic equation with polytropic index $n=3$ and the realistic…

General Relativity and Quantum Cosmology · Physics 2022-11-29 Artyom V. Astashenok , Sergey D. Odintsov , Vasilis Oikonomou

We summarize recent improvements in model atmosphere and internal structure of faint white dwarfs. We derive an analytical cooling theory which illustrates the effects of various physical processes on the energy budget and the cooling…

Astrophysics · Physics 2007-05-23 Gilles Chabrier

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 stellar embers depleted of nuclear energy sources that cool over billions of years. These stars, which are supported by electron degeneracy pressure, reach densities of 1e7 grams per cubic centimetre in their cores. It has…

White dwarfs are the final remnants of low- and intermediate-mass stars. Their evolution is essentially a cooling process that lasts for $\sim 10$ Gyr. Their observed properties provide information about the history of the Galaxy, its dark…

Solar and Stellar Astrophysics · Physics 2016-10-05 Enrique García-Berro , Terry D. Oswalt

We investigate the luminosity suppression and its effect on the mass-radius relation as well as cooling evolution of highly magnetised white dwarfs. Based on the effect of magnetic field relative to gravitational energy, we suitably modify…

Solar and Stellar Astrophysics · Physics 2022-04-06 Mukul Bhattacharya , Alexander J. Hackett , Abhay Gupta , Christopher A. Tout , Banibrata Mukhopadhyay

Static and uniformly rotating, cold and hot white dwarfs are investigated both in Newtonian gravity and general theory of relativity, employing the well-known Chandrasekhar equation of state. The mass-radius, mass-central density,…

Solar and Stellar Astrophysics · Physics 2020-06-04 Kuantay Boshkayev

Thanks to their continuous cooling and relative simplicity, white dwarf stars are routinely used to measure the ages of stellar populations. The usefulness of white dwarfs as cosmochronometers depends on the availability of accurate cooling…

Solar and Stellar Astrophysics · Physics 2020-08-19 Simon Blouin , Nathaniel R. Shaffer , Didier Saumon , Charles E. Starrett

Recently, some over-luminous Ia supernovaes are found, suggesting that their progenitors are white dwarfs more massive than the Chandrasekhar limit, which perhaps result from ultra-strong magnetic field inside the white dwarfs. We present…

High Energy Astrophysical Phenomena · Physics 2015-05-06 Qi-Xiang Zou , Xin-He Meng

In this work, cold and hot, static and rotating white dwarf stars are investigated within the framework of classical physics, employing the Chandrasekhar equation of state. The main parameters of white dwarfs such as the central density,…

Solar and Stellar Astrophysics · Physics 2019-05-20 Kuantay Boshkayev
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