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Related papers: Chandrasekhar Mass Limit of White Dwarfs in Modifi…

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In recent years, the idea of sub- and super-Chandrasekhar limiting mass white dwarfs (WDs), which are potential candidates to produce under- and over-luminous type Ia supernovae, respectively, has been a key interest in the scientific…

General Relativity and Quantum Cosmology · Physics 2022-02-04 Surajit Kalita , Lupamudra Sarmah

Modified dispersion relations from effective field theory are shown to alter the Chandrasekhar mass limit. At exceptionally high densities, the modifications affect the pressure of a degenerate electron gas and can increase or decrease the…

Astrophysics · Physics 2010-06-22 Michael Gregg , Seth A. Major

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

While computing the Fermi degeneracy pressure of electrons in a white dwarf star within the framework of hydrostatic equilibrium, we depart from the extant practice of treating the electrons as a free fermion gas, by including the effect of…

General Relativity and Quantum Cosmology · Physics 2017-08-22 Anarya Ray , Pronobesh Maity , Parthasarathi Majumdar

In this work we investigate the equilibrium configurations of white dwarfs in a modified gravity theory, na\-mely, $f(R,T)$ gravity, for which $R$ and $T$ stand for the Ricci scalar and trace of the energy-momentum tensor, respectively.…

General Relativity and Quantum Cosmology · Physics 2017-12-20 G. A. Carvalho , R. V. Lobato , P. H. R. S. Moraes , José D. V. Arbañil , R. M. Marinho , E. Otoniel , M. Malheiro

We compute static equilibria of white dwarf stars containing strong poloidal magnetic field, and present the modification of white dwarf mass-radius relation caused by the magnetic field. We find that a maximum white dwarf mass of about…

Solar and Stellar Astrophysics · Physics 2014-11-11 Prasanta Bera , Dipankar Bhattacharya

The idea of possible modification to gravity theory, whether it is in the Newtonian or general relativistic premises, is there for quite sometime. Based on it, astrophysical and cosmological problems are targeted to solve. But none of the…

General Relativity and Quantum Cosmology · Physics 2022-01-02 Agrim Sharma , Banibrata Mukhopadhyay

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

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

Scalar-tensor theories of gravity can lead to modifications of the gravitational force inside astrophysical objects. We exhibit that compact stars such as white dwarfs provide a unique set-up to test beyond Horndeski theories of ${\rm G}^3$…

Cosmology and Nongalactic Astrophysics · Physics 2016-04-20 Rajeev Kumar Jain , Chris Kouvaris , Niklas Grønlund Nielsen

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

We explore the luminosity L of magnetized white dwarfs and its effect on the mass-radius relation. We self-consistently obtain the interface between the electron degenerate gas dominated inner core and the outer ideal gas surface layer or…

Solar and Stellar Astrophysics · Physics 2020-06-19 Abhay Gupta , Banibrata Mukhopadhyay , Christopher A. Tout

Massive, highly magnetized white dwarfs with fields up to $10^9$ G have been observed and theoretically used for the description of a variety of astrophysical phenomena. Ultramagnetized white dwarfs with uniform interior fields up to…

Solar and Stellar Astrophysics · Physics 2014-09-29 J. G. Coelho , R. M. Marinho , M. Malheiro , R. Negreiros , D. L. Cáceres , J. A. Rueda , R. Ruffini

We address the issue of stability of recently proposed significantly super-Chandrasekhar white dwarfs. We present stable solutions of magnetostatic equilibrium models for super-Chandrasekhar white dwarfs pertaining to various magnetic field…

Solar and Stellar Astrophysics · Physics 2014-06-25 Upasana Das , Banibrata Mukhopadhyay

The mass radius relationship of white dwarfs, near the Chandrasekhar Limit, is derived for a toy model of uniform density, using the variational principle. A power law scaling, reminiscent of those found in 2nd order phase transitions, is…

Astrophysics · Physics 2007-05-23 Sayan Chakraborti

We consider a relativistic, degenerate, electron gas under the influence of a strong magnetic field, which describes magnetized white dwarfs. Landau quantization changes the density of states available to the electrons, thus modifying the…

Solar and Stellar Astrophysics · Physics 2013-04-12 Upasana Das , Banibrata Mukhopadhyay

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 clarify important physics issues related to the recently established new mass limit for magnetized white dwarfs which is significantly super-Chandrasekhar. The issues include, justification of high magnetic field and the corresponding…

Solar and Stellar Astrophysics · Physics 2014-06-05 Upasana Das , Banibrata Mukhopadhyay

After the prediction of many sub- and super-Chandrasekhar (at least a dozen for the latter) limiting mass white dwarfs, hence apparently peculiar class of white dwarfs, from the observations of luminosity of type Ia supernovae, researchers…

High Energy Astrophysical Phenomena · Physics 2021-03-09 Surajit Kalita , Banibrata Mukhopadhyay

Since 2012, we have initiated a new idea showing that the mass of highly magnetized or modified Einstein's gravity induced white dwarfs could be significantly super-Chandrasekhar with a different mass-limit. This discovery has several…