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Related papers: Spheroidal magnetic stars rotating in vacuum

200 papers

We investigate the interaction of differential rotation and a misaligned magnetic field. The incompressible magnetohydrodynamic equations are solved numerically for a free-decay problem. In the kinematic limit, differential rotation…

Solar and Stellar Astrophysics · Physics 2015-06-11 Xing Wei , Jeremy Goodman

We present, for the first time, the structure of the axisymmetric force-free magnetosphere of an aligned rotating magnetic dipole, in the case in which there exists a sufficiently large charge density (whose origin we do not question) to…

Astrophysics · Physics 2011-07-18 Ioannis Contopoulos , Demosthenes Kazanas , Christian Fendt

We consider the slowly rotating relativistic stars with a uniform angular velocity in the scalar-tensor gravity, and examine the rotational effect around such compact objects. For this purpose, we derive a 2nd order differential equation…

High Energy Astrophysical Phenomena · Physics 2015-06-12 Hajime Sotani

Neutron star electromagnetic activity produces pairs that fill their magnetosphere represented to the zeroth order by the force-free approximation. Neither dissipation nor acceleration nor radiation from charged particles is expected from…

High Energy Astrophysical Phenomena · Physics 2021-01-06 Jérôme Pétri

We resolve the paradox that although magnetic collimation of an isotropic solar wind results in an enhancement of its proton flux along the polar directions, several observations indicate a wind proton flux peaked at the equator. To that…

Astrophysics · Physics 2007-05-23 K. Tsinganos , S. Bogovalov

We calculate non-axisymmetric oscillations of uniformly rotating polytropes magnetized with a purely toroidal magnetic field, taking account of the effects of the deformation due to the magnetic field. As for rotation, we consider only the…

Solar and Stellar Astrophysics · Physics 2015-06-24 Hidetaka Asai , Umin Lee , Shijun Yoshida

The problem of the stability of magnetic fields in stars has a long history and has been investigated in detail in perturbation theory. Here we consider the nonlinear evolution of a non-rotating neutron star with a purely poloidal magnetic…

General Relativity and Quantum Cosmology · Physics 2015-03-19 Riccardo Ciolfi , Samuel K. Lander , Gian Mario Manca , Luciano Rezzolla

Context. Stars experience rapid contraction or expansion at different phases of their evolution. Modelling the angular momentum and chemical elements transport occurring during these phases remains an unsolved problem. Aims. We study a…

Solar and Stellar Astrophysics · Physics 2021-05-05 B. Gouhier , F. Lignières , L. Jouve

Magnetar magnetospheres are believed to be strongly twisted, due to shearing of the stellar crust by internal magnetic stresses. We present time-dependent axisymmetric simulations showing in detail the evolution of relativistic force-free…

High Energy Astrophysical Phenomena · Physics 2015-06-16 Kyle Parfrey , Andrei M. Beloborodov , Lam Hui

In this manuscript, we investigate the behavior of stellar structure through embedding approach in $f(R, \phi, X)$ modified theory of gravity, where $R$ denotes the Ricci scalar, $\phi$ represents the scalar potential and $X$ indicates the…

General Relativity and Quantum Cosmology · Physics 2024-04-02 Adnan Malik , Yonghui Xia , Ayesha Almas , M. Farasat Shamir

The paper deals with the static spherically symmetric wormhole solutions in $f(R)$-modified gravity theory with anisotropic matter field and for some particular choices for the shape functions. The present work may be considered as an…

General Relativity and Quantum Cosmology · Physics 2021-08-11 Bikram Ghosh , Saugata Mitra , Subenoy Chakraborty

We couple internal torsional, magneto-elastic oscillations of highly magnetized neutron stars (magnetars) to their magnetospheres. The corresponding axisymmetric perturbations of the external magnetic field configuration evolve as a…

High Energy Astrophysical Phenomena · Physics 2015-06-22 Michael Gabler , Pablo Cerdá-Durán , Nikolaos Stergioulas , José A. Font , Ewald Müller

We extend our previous study of equilibrium solutions of non-rotating force-free magnetospheres of neutron stars. We show that multiple solutions exist for the same sets of parameters, implying that the solutions are degenerate. We are able…

High Energy Astrophysical Phenomena · Physics 2018-10-11 Taner Akgün , Pablo Cerdá-Durán , Juan Antonio Miralles , José A. Pons

The purpose of this thesis is to obtain more realistic equations of state to describe the matter forming magnetized white dwarfs, and use them to solve its structure equations. The equations of state are determined by considering the weak…

High Energy Astrophysical Phenomena · Physics 2016-01-06 D. Alvear Terrero , D. Manreza Paret , A. Pérez Martínez

We present the first self-consistent global simulations of pulsar magnetospheres with operating $e^\pm$ discharge. We focus on the simple configuration of an aligned or anti-aligned rotator. The star is spun up from zero (vacuum) state to a…

High Energy Astrophysical Phenomena · Physics 2014-10-28 Alexander Y. Chen , Andrei M. Beloborodov

A new set of vector solutions to Maxwell's equations based on solutions to the wave equation in spheroidal coordinates allows laser beams to be described beyond the paraxial approximation. Using these solutions allows us to calculate the…

Optics · Physics 2015-03-13 Martin Zeppenfeld , Pepijn W. H. Pinkse

The electrophoretic mobility of a spherical particle is well understood, yet how particle shape modifies this mobility at arbitrary Debye length remains an open question. Here, we compute the electrophoretic mobility of a nearly spherical…

Fluid Dynamics · Physics 2026-04-24 Arkava Ganguly , Ankur Gupta

Analytical solutions to the wave equation in spheroidal coordinates in the short wavelength limit are considered. The asymptotic solutions for the radial function are significantly simplified, allowing scalar spheroidal wave functions to be…

Optics · Physics 2009-10-07 Martin Zeppenfeld

We show that a rigidly rotating, homogeneous ellipsoid of revolution threaded by a uniform, coaxial magnetic field is a possible figure of equilibrium. While the spheroidal shape is fully preserved, the rotation rate is modified.…

Astrophysics of Galaxies · Physics 2024-06-28 Jean-Marc Huré , Clément Staelen

We study of the collapse of a magnetized spherical star to a black hole in general relativity theory. The matter and gravitational fields are described by the exact Oppenheimer-Snyder solution for the collapse of a spherical, homogeneous…

Astrophysics · Physics 2008-11-26 Thomas W. Baumgarte , Stuart L. Shapiro