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Related papers: GRMHD Simulations of Accreting Neutron Stars with …

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We present the results of 2.5-dimensional resistive magnetohydrodynamic (MHD) simulations of the magnetic interaction between a weakly magnetized neutron star and its accretion disk. General relativistic effects are simulated by using the…

Astrophysics · Physics 2009-11-10 Yoshiaki Kato , Mitsuru Hayashi , Ryoji Matsumoto

Aims. A realistic model of magnetic linkage between a central object and its accretion disk is a prerequisite for understanding the spin history of stars and stellar remnants. To this end, we aim to provide an analytic model in agreement…

Solar and Stellar Astrophysics · Physics 2023-10-04 Miljenko Čemeljić , Włodek Kluźniak , Varadarajan Parthasarathy

We carried out two dimensional high-resolution magnetohydrodynamic (MHD) simulations of an accretion disk around a weakly magnetized neutron star. General relativistic effects are taken into account by using pseudo-Newtonian potential of…

Astrophysics · Physics 2009-11-06 Y. Kato , H. R. Hayashi , S. Miyaji , R. Matsumoto

Global 3-D magnetohydrodynamical simulations have been conducted to study magnetospheric accretion around stars with various spin rates. For slow rotators, characterized by a fastness parameter $\omega_s\lesssim 0.78$, the disk's inner edge…

Solar and Stellar Astrophysics · Physics 2025-02-26 Zhaohuan Zhu

Magnetohydrodynamic (MHD) simulations have been used to study disk accretion to a rotating magnetized star with an aligned dipole moment. Quiescent initial conditions were developed in order to avoid the fast initial evolution seen in…

Astrophysics · Physics 2009-11-07 M. M. Romanova , G. V. Ustyugova , A. V. Koldoba , R. V. E. Lovelace

We investigate the rotational dynamics of disk accretion around a strongly magnetized neutron star with an aligned dipole field. The magnetospheric field is assumed to thread the disk plasma both inside and outside the corotation radius. As…

Astrophysics · Physics 2009-11-10 M. Hakan Erkut , M. Ali Alpar

The discovery of the ultraluminous X-ray pulsar M82 X-2 has stimulated lively discussion on the nature of the accreting neutron star. In most of the previous studies the magnetic field of the neutron star was derived from the observed…

High Energy Astrophysical Phenomena · Physics 2017-04-12 Kun Xu , Xiang-Dong Li

The recent discovery of the first known accretion-powered millisecond pulsar with the Rossi X-Ray Timing Explorer provides the first direct probe of the interaction of an accretion disk with the magnetic field of a weakly magnetic (B<10^10…

Astrophysics · Physics 2009-10-30 Dimitrios Psaltis , Deepto Chakrabarty

We perform magnetohydrodynamic simulations in full general relativity (GRMHD) of quasi-circular, equal-mass, binary neutron stars that undergo merger. The initial stars are irrotational, $n=1$ polytropes and are magnetized. We explore two…

High Energy Astrophysical Phenomena · Physics 2016-06-15 Milton Ruiz , Ryan N. Lang , Vasileios Paschalidis , Stuart L. Shapiro

We report results from calculations investigating stationary magnetic field configurations in accretion discs around magnetised neutron stars. Our strategy is to start with a very simple model and then progressively improve it providing…

Solar and Stellar Astrophysics · Physics 2014-11-20 L. Naso , J. C. Miller

We perform 2D axisymmetric radiative relativistic MHD simulations of radiation pressure supported neutron star accretion columns in split-monopole magnetic fields. The accretion columns exhibit quasi-periodic oscillations, which manifest in…

High Energy Astrophysical Phenomena · Physics 2023-02-01 Lizhong Zhang , Omer Blaes , Yan-Fei Jiang

Millisecond x-ray pulsars have weak magnetic dipole moments of $\sim 10^{16}$\,T\,m$^3$ compared to ordinary X-ray pulsars with dipole moments of $10^{20}$\,T\,m$^3$. For this reason a surrounding accretion disc can extend closer to the…

High Energy Astrophysical Phenomena · Physics 2010-11-12 Solomon Belay Tessema , Ulf Torkelsson

We present a comprehensive analysis of four near-Eddington black hole accretion models computed by solving the GRMHD equations with full radiation transport. This study focuses on the dynamical effects of magnetic field topology and black…

High Energy Astrophysical Phenomena · Physics 2026-03-09 Lizhong Zhang , James M. Stone , Shane W. Davis , Yan-Fei Jiang , Patrick D. Mullen , Christopher J. White

We perform magnetohydrodynamic simulations in full general relativity (GRMHD) of a binary black hole-neutron star on a quasicircular orbit that undergoes merger. The binary mass ratio is 3:1, the black hole initial spin parameter $a/m=0.75$…

High Energy Astrophysical Phenomena · Physics 2015-06-11 Vasileios Paschalidis , Milton Ruiz , Stuart L. Shapiro

Neutron stars exhibit magnetic fields and densities far beyond those achievable in terrestrial laboratories, offering a natural probe of strongly interacting matter under extreme conditions. Using observationally anchored mass-radius…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-13 Abriana Lyda , Prajwal MohanMurthy

Merging binaries consisting of two neutron stars (NSs) or an NS and a stellar-mass black hole typically form a massive accretion torus around the remnant black hole or long-lived NS. Outflows from these neutrino-cooled accretion disks…

High Energy Astrophysical Phenomena · Physics 2018-06-26 Daniel M. Siegel , Brian D. Metzger

We analyze the effect of the quadrupole component in the mass distribution of a rapidly rotating neutron star on energy release in the boundary layer on the surface of the accreting star and in the accretion disk in the cases where the…

Astrophysics · Physics 2007-05-23 N. R. Sibgatullin , R. A. Sunyaev

In this paper we discuss the spin-equilibrium of accreting neutron stars in LMXBs. We demonstrate that, when combined with a naive spin-up torque, the observed data leads to inferred magnetic fields which are at variance with those of…

Astrophysics · Physics 2009-11-10 N. Andersson , K. Glampedakis , B. Haskell , A. L. Watts

In this work we have estimated upper and lower limits to the strength of the magnetic dipole moment of all 14 accreting millisecond X-ray pulsars observed with the Rossi X-ray Timing Explorer (RXTE). For each source we searched the archival…

High Energy Astrophysical Phenomena · Physics 2015-08-19 Dipanjan Mukherjee , Peter Bult , Michiel van der Klis , Dipankar Bhattacharya

We run two GRRMHD simulations of super-Eddington accretion disks around a black hole and a non-magnetized, non-rotating neutron star. The neutron star was modeled using a reflective inner boundary condition. We observe the formation of a…

High Energy Astrophysical Phenomena · Physics 2018-07-04 David Abarca , Włodek Kluźniak , Aleksander Sądowski