English
Related papers

Related papers: Magnetically supramassive and hypermassive compact…

200 papers

We obtain equilibrium solutions for rotating compact stars including the special relativistic effects. The gravity is assumed to be Newtonian, but we used the active mass density, which takes into account all the energies such as motions of…

High Energy Astrophysical Phenomena · Physics 2015-05-13 Jinho Kim , Hee Il Kim , Hyung Mok Lee

We study the structure of relativistic stars in $\mathcal{R}+\alpha \mathcal{R}^{2}$ theory using the method of matched asymptotic expansion to handle the higher order derivatives in field equations arising from the higher order curvature…

General Relativity and Quantum Cosmology · Physics 2017-10-24 Savaş Arapoğlu , Sercan Çıkıntoğlu , K. Yavuz Ekşi

Although barotropic matter does not constitute a realistic model for magnetic stars, it would be interesting to confirm a recent conjecture that states that magnetized stars with a barotropic equation of state would be dynamically unstable…

Solar and Stellar Astrophysics · Physics 2015-06-15 Cristobal Armaza , Andreas Reisenegger , Juan Alejandro Valdivia , Pablo Marchant

Using a sample of nine massive compact galaxies at z ~ 2.3 with rest-frame optical spectroscopy and comprehensive U through 8um photometry we investigate how assumptions in SED modeling change the stellar mass estimates of these galaxies,…

Astrophysics of Galaxies · Physics 2014-11-20 Adam Muzzin , Pieter van Dokkum , Marijn Franx , Danilo Marchesini , Mariska Kriek , Ivo Labbé

Mass-varying massive gravity allows the graviton mass to vary according to different environments. We investigate neutron star and white dwarf solutions in this theory and find that the graviton mass can become very large near the compact…

General Relativity and Quantum Cosmology · Physics 2020-03-31 Xue Sun , Shuang-Yong Zhou

The magnetic field is believed to play an important role in at least some core-collapse supernovae if its magnitude reaches $10^{15}\,\rm{G}$, which is a typical value for a magnetar. In the presence of fast rotation, such a strong magnetic…

High Energy Astrophysical Phenomena · Physics 2020-01-17 M. Bugli , J. Guilet , M. Obergaulinger , P. Cerdá-Durán , M. Á. Aloy

Supermassive stars (SMSs) are candidates for being progenitors of supermassive quasars at high redshifts. However, their formation process requires strong mechanisms that would be able to extract the angular momentum of the gas that the…

Solar and Stellar Astrophysics · Physics 2019-03-13 Lionel Haemmerlé , Georges Meynet

We revisit in this work the problem of the maximum masses of magnetized White Dwarfs (WD). The impact of a strong magnetic field onto the structure equations is addressed. The pressures become anisotropic due to the presence of the magnetic…

High Energy Astrophysical Phenomena · Physics 2015-10-14 D. Manreza Paret , A. Perez Martinez , J. E. Horvath

Charged particles at the crust of compact stars may be ejected and accelerated by the electric field generated due to the rotation of the magnetized star. For neutron or hybrid stars, the negatively charged particles are usually electrons,…

High Energy Astrophysical Phenomena · Physics 2020-10-28 Debojoti Kuzur , Rupamoy Bhattacharyya , Ritam Mallick

We extend a known solution generating technique for isotropic fluids in order to construct more general models of anisotropic stars with poloidal magnetic fields. In particular, we discuss the magnetized versions of some well-known exact…

General Relativity and Quantum Cosmology · Physics 2018-06-06 Cristian Stelea , Marina-Aura Dariescu , Ciprian Dariescu

The current model explores spherically symmetric anisotropic compact stars within the Rastall theory of gravity. By employing the Krori and Barua metric ansatz (K.D. Krori and J. Barua, J. Phys. A: Math. Gen. 8 (1975) 508), we derive a set…

General Relativity and Quantum Cosmology · Physics 2025-05-29 Sourav Biswas , Debadri Bhattacharjee , Pradip Kumar Chattopadhyay

Aims. Many recent observations of pulsars and magnetars can be interpreted in terms of neutron stars (NS) with multipole electromagnetic fields. As a first approximation, we investigate the multipole magnetic and electric fields in the…

High Energy Astrophysical Phenomena · Physics 2020-07-07 S. Bonazzola , F. Mottez , J. Heyvaerts

We study properties of boson stars consisting of ultra-light scalar dark matter with repulsive self-interactions. We investigate the origin of the maximum mass of spherically symmetric stable stars which emerges only when solving the full…

High Energy Physics - Phenomenology · Physics 2019-04-17 Djuna Croon , JiJi Fan , Chen Sun

We present the formalism and numerical results for torsional oscillations of relativistic stars endowed with a strong dipole magnetic field. We do a systematic search of parameter space by computing torsional mode frequencies for various…

Astrophysics · Physics 2008-11-26 H. Sotani , K. D. Kokkotas , N. Stergioulas

Models of rotationally-driven dynamos in stellar radiative zones have suggested that magnetohydrodynamic transport of angular momentum and chemical composition can dominate over the otherwise purely hydrodynamic processes. A proper…

Solar and Stellar Astrophysics · Physics 2015-06-05 Adrian T. Potter , Shashikumar M. Chitre , Christopher A. Tout

One of the key questions in Astrophysics concerns the issue of whether there exists an upper-mass limit to stars, and if so, what physical mechanism sets this limit, which might also determine if the upper-mass limit is metallicity (Z)…

Solar and Stellar Astrophysics · Physics 2018-07-25 Jorick S. Vink

We investigate the stability of strange quark matter and the properties of the cor- responding strange stars, within a wide range of quark mass scaling. The calculation shows that the resulting maximum mass always lies between 1.5M_{sun}…

Solar and Stellar Astrophysics · Physics 2010-07-29 A. Li

Upper limits for the mass-radius ratio and total charge are derived for stable charged general relativistic matter distributions. For charged compact objects the mass-radius ratio exceeds the value 4/9 corresponding to neutral stars.…

General Relativity and Quantum Cosmology · Physics 2009-11-07 M. K. Mak , Peter N. Dobson , T. Harko

Observational evidence for the existence of cosmic magnetic fields in intergalactic space coherent over Mpc scales is presented. Using an unprecedentedly large sample of Faraday rotation measures of radio sources from the NRAO VLA Sky…

Cosmology and Nongalactic Astrophysics · Physics 2010-07-16 Jounghun Lee , Ue-Li Pen , A. Russell Taylor , Jeroen M. Stil , Caleb Sunstrum

The helicity of a magnetic field is a fundamental property that is conserved in ideal MHD. It can be explored in the stellar context by mapping large-scale magnetic fields across stellar surfaces using Zeeman-Doppler imaging. A recent study…

Solar and Stellar Astrophysics · Physics 2021-03-12 K. Lund , M. Jardine , A. J. B. Russell , J. -F. Donati , R. Fares , C. P. Folsom