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Related papers: White dwarfs in an ungravity-inspired model

200 papers

We consider a particular effect which can be expected in scenarios of deviations from Special Relativity induced by Planckian physics: the loss of additivity in the total energy of a system of particles. We argue about the necessity to…

General Relativity and Quantum Cosmology · Physics 2015-06-17 J. M. Carmona , J. L Cortes , R. Gracia-Ruiz , N. Loret

From the low-mass non-relativistic case to the relativistic limit, the density profile of a white dwarf is used to evaluate the complexity measure. Similarly to the recently reported atomic case where, by averaging shell effects, complexity…

Astrophysics · Physics 2014-11-18 J. Sanudo , A. F. Pacheco

The limiting mass of cold white dwarfs was first calculated by E. Stoner in an approximate model of a uniform star and was soon reduced by ~20% in papers by S. Chandrasekhar and L. D. Landau based on an exact solution of the equations for…

Solar and Stellar Astrophysics · Physics 2022-04-20 G. S. Bisnovatyi-Kogan , E. A. Patraman

In recent years a number of white dwarfs has been observed with very high surface magnetic fields. We can expect that the magnetic field in the core of these stars would be much higher (~ 10^{14} G). In this paper, we analytically study the…

Solar and Stellar Astrophysics · Physics 2012-05-09 Aritra Kundu , Banibrata Mukhopadhyay

In the vast expanse of our galaxy, white dwarfs (WDs) are natural sentinels, capturing the enigmatic dark matter (DM) particles that incessantly traverse their interiors. These celestial bodies provide a unique vantage point for probing…

High Energy Physics - Phenomenology · Physics 2024-06-06 Jia-Shu Niu

As white-dwarf (WD) stars cool, they go through one or more stages of $g$(gravity)-mode pulsational instability, becoming multiperiodic variable stars. Stars passing through these instability domains allow astronomers to study their…

Solar and Stellar Astrophysics · Physics 2022-03-09 A. H. Córsico

We explore the internal structures of the white dwarfs in two different modified theories of gravity: (i) scalar-tensor-vector gravity and (ii) beyond Horndeski theories of $G_3$ type. The modification of the gravitational force inside the…

General Relativity and Quantum Cosmology · Physics 2023-01-31 Khursid Alam , Tousif Islam

Identification of white dwarfs (WD) with main-sequence (MS) companions and characterization of their properties can put important constraints on our understanding of binary stellar evolution and guide the theoretical predictions for a wide…

Solar and Stellar Astrophysics · Physics 2023-11-27 Prasanta K. Nayak , Anindya Ganguly , Sourav Chatterjee

Our ongoing spectroscopic survey of high proper motion stars is a rich source of new magnetic white dwarfs. We present a few examples among cool white dwarfs showing the effect of field strength and geometry on the observed optical…

Solar and Stellar Astrophysics · Physics 2018-01-18 S. Vennes , A. Kawka , L. Ferrario , E. Paunzen

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

Masses are one of the most difficult stellar properties to measure. In the case of the white-dwarf companions of Barium stars, the situation is worse. These stars are dim, cool, and difficult to observe via direct methods. However, Ba stars…

Solar and Stellar Astrophysics · Physics 2023-03-15 A. Escorza , R. J. De Rosa

White dwarfs with infrared excess emission provide a window into the late stages of stellar evolution and the dynamics of circumstellar environments. Using data from the Hobby-Eberly Telescope Dark Energy Experiment (HETDEX), we…

Measuring the mass-radius relation of individual white dwarfs is an empirically challenging task that has been performed for only a few dozen stars. We measure the white dwarf mass-radius relation using gravitational redshifts and radii of…

Measuring the masses of companions to single-line spectroscopic binary stars is (in general) not possible because of the unknown orbital plane inclination. Even when the mass of the visible star can be measured, only a lower limit can be…

Solar and Stellar Astrophysics · Physics 2015-06-23 Jeff J. Andrews , Adrian M. Price-Whelan , Marcel A. Agüeros

Magnetic fields are present in roughly 10% of white dwarfs. These fields affect the structure and evolution of such stars, and may provide clues about their earlier evolution history. Particularly important for statistical studies is the…

Solar and Stellar Astrophysics · Physics 2019-03-06 John D. Landstreet , Stefano Bagnulo

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

There has been a growing interest within the astrophysics community in highly magnetized and fast-spinning white dwarfs (WDs), commonly referred to as HMWDs. WDs with these characteristics are quite uncommon and possess magnetic fields…

Solar and Stellar Astrophysics · Physics 2024-12-20 M. F. Sousa , E. Otoniel , J. G. Coelho , J. C. N. de Araujo

In this work, we investigate the relativistic structure of white dwarfs (WDs) within the framework of modified gravity theory $f(R, T, L_m) = R + \alpha T L_m$, which introduces a non-minimal coupling between matter and curvature. Using a…

General Relativity and Quantum Cosmology · Physics 2026-03-05 Edson Otoniel , Juan M. Z. Pretel , Clésio E. Mota , César O. V. Flores , Victor B. T. Alves , Franciele M. da Silva

In this study, we demonstrate the efficacy of the Ultraviolet Imaging Telescope (UVIT) in identifying and characterizing white dwarfs (WDs) within the Milky Way Galaxy. Leveraging the UVIT point source catalogue towards SMC and…

The vast majority of stars that populate the Universe will end their evolution as white-dwarf stars. Applications of white dwarfs include cosmochronology, evolution of planetary systems, and also as laboratories to study non-standard…

Solar and Stellar Astrophysics · Physics 2020-10-14 Alejandro H. Córsico