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Related papers: Generalized Flows around Neutron Stars

200 papers

A model for advection-dominated accretion flows (ADAFs) in a global magnetic field is proposed. In contrast to the well known ADAF models in which the viscosity of a fluid determines both angular momentum transfer and energy dissipation in…

Astrophysics · Physics 2009-10-31 Osamu Kaburaki

Evidence of surface magnetism is now observed on an increasing number of cool stars. The detailed manner by which dynamo-generated magnetic fields giving rise to starspots traverse the convection zone still remains unclear. Some insight…

Solar and Stellar Astrophysics · Physics 2017-09-20 Maria A. Weber , Matthew K. Browning , Suzannah Boardman , Joshua Clarke , Samuel Pugsley , Edward Townsend

Both relativistic and non-relativistic two-fluid models of neutron star cores are constructed, using the constrained variational formalism developed by Brandon Carter and co-workers. We consider a mixture of superfluid neutrons and…

Astrophysics · Physics 2008-08-05 N. Chamel

We present analytical and numerical solutions which describe a hot, viscous, two-temperature accretion flow onto a rotating neutron star or any other rotating compact star with a surface. We assume Coulomb coupling between the protons and…

Astrophysics · Physics 2009-11-06 Mikhail Medvedev , Ramesh Narayan

The interiors of mature neutron stars are expected to be superfluid. Superfluidity of matter on the microscopic scale can have a number of large scale, potentially observable consequences, as the superfluid component of the star can now…

High Energy Astrophysical Phenomena · Physics 2019-12-11 Vadym Khomenko , Marco Antonelli , Brynmor Haskell

We develop a Lagrangian perturbation framework for rotating non-relativistic superfluid neutron stars. This leads to the first generalization of classic work on the stability properties of rotating stars to models which account for the…

Astrophysics · Physics 2009-11-10 N. Andersson , G. L. Comer , K. Grosart

We present here the solutions of magnetized accretion flows on to a compact object with hard surface such as neutron stars. The magnetic field of the central star is assumed dipolar and the magnetic axis is assumed to be aligned with the…

High Energy Astrophysical Phenomena · Physics 2018-03-14 Kuldeep Singh , Indranil Chattopadhyay

We carry out a series of numerical simulations of viscous accretion flows having a reasonable spatial distribution of the viscosity parameter. We add the power-law cooling throughout the flow. We show that, in agreement with the theoretical…

High Energy Astrophysical Phenomena · Physics 2015-06-12 Kinsuk Giri , Sandip K. Chakrabarti

Neutron stars that are cold enough should have two or more superfluids/supercondutors in their inner crusts and cores. The implication of superfluidity/superconductivity for equilibrium and dynamical neutron star states is that each…

General Relativity and Quantum Cosmology · Physics 2009-11-10 G. L. Comer

We perform as the first time hydrodynamic simulations to study the properties of hot accretion flow (HAF) around a neutron star (NS). The energy carried by the HAF will eventually be radiated out at the surface of the NS. The emitted…

High Energy Astrophysical Phenomena · Physics 2019-05-01 De-Fu Bu , Er-Lin Qiao , Xiao-Hong Yang

Ten years have passed since the global solutions of advective accretion disks around black holes and neutron stars were first discovered. Since then they are enjoying support from observers almost on a daily basis, more so in recent days…

Astrophysics · Physics 2007-05-23 S. K. Chakrabarti

We carry out numerical simulation of accretion flows around a black hole in presence of both viscous and cooling effects. Instead of using a constant $\alpha$ parameter throughout the simulation grid, we assume that $\alpha$ is maximum on…

High Energy Astrophysical Phenomena · Physics 2013-10-09 Kinsuk Giri , Sandip K. Chakrabarti

This work is concerned with advancing multi-fluid models in General Relativity, and in particular focuses on the modelling of dissipative fluids and turbulent flows. Such models are required for an accurate description of neutron star…

High Energy Astrophysical Phenomena · Physics 2023-07-13 Thomas Celora

We have developed a theoretical model and a numerical code for stationary rotating superfluid neutron stars in full general relativity. The underlying two-fluid model is based on Carter's covariant multi-fluid hydrodynamic formalism. The…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Reinhard Prix , Jerome Novak , G. L. Comer

We review the advantages of fitting with a Two Component Advective Flow (TCAF) which uses only four physical parameters. We then present the results of hydrodynamic simulations to highlight the fact that the primary component of a black…

High Energy Astrophysical Phenomena · Physics 2024-09-19 Sandip Kumar Chakrabarti

We generalize the recent Newtonian two-component charged fluid models for white dwarf stars of Krivoruchenko, Nadyozhin and Yudin and of Hund and Kiessling to the context of general relativity. We compare the equations and numerical…

General Relativity and Quantum Cosmology · Physics 2021-10-05 Erik Amorim , Parker Hund

In this paper we reconsider the problem of magnetic field diffusion in neutron star cores. We model the star as consisting of a mixture of neutrons, protons and electrons, and allow for particle reactions and binary collisions between…

Solar and Stellar Astrophysics · Physics 2015-05-20 K. Glampedakis , D. I. Jones , L. Samuelsson

We present the effects of the vertical convection on the structure and luminosity of the neutrino-dominated accretion flow (NDAF) around a stellar-mass black hole in spherical coordinates. We found that the convective energy transfer can…

High Energy Astrophysical Phenomena · Physics 2015-05-27 Tong Liu , Wei-Min Gu , Norita Kawanaka , Ang Li

For treatment of the layers below the crust of a neutron star it is useful to employ a relativistic model involving three independently moving constituents, representing superfluid neutrons, superfluid protons, and degenerate negatively…

Astrophysics · Physics 2007-05-23 Brandon Carter

We use Smoothed Particle Hydrodynamics to study viscous accretion flows around a weakly magnetic neutron star. We show the formation of multiple ``boundary" layers in presence of both cooling and viscosity. We find that with the…

High Energy Astrophysical Phenomena · Physics 2019-06-26 Ayan Bhattacharjee , Sandip K. Chakrabarti