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Related papers: Two-Component Advective Flows around Neutron Stars

200 papers

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 consider hot, two-temperature, viscous accretion onto a rotating, unmagnetized neutron star. We assume Coulomb coupling betweenthe protons and electrons, and free-free cooling from the electrons. We show that the accretion flow has an…

Astrophysics · Physics 2009-10-31 Mikhail V. Medvedev , Ramesh Narayan

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

Astrophysics · Physics 2009-11-06 Mikhail V. Medvedev

We describe astrophysical processes around a black hole keeping primarily the physics of accretion in mind. In Section 1, we briefly discuss the formation, evolution and detection of black holes. We also discuss the difference of flow…

Astrophysics · Physics 2009-10-28 Sandip K. Chakrabarti

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

We wish to investigate the effects of cooling of the Compton cloud on the outflow formation rate in an accretion disk around a black hole. We carry out a time dependent numerical simulation where both the hydrodynamics and the radiative…

High Energy Astrophysical Phenomena · Physics 2012-10-15 Sudip K. Garain , Himadri Ghosh , Sandip K. Chakrabarti

We present two numerical simulations of an accretion flow from a rotating torus onto a compact object with and without a solid surface -- representing a neutron star and a black hole -- and investigate its influence on the process of jet…

Astrophysics · Physics 2009-11-10 Matthias Stute , Jose Gracia , Max Camenzind

We study the time dependent properties of sub-Keplerian viscous accretion flow around the black holes. We find that rotating matter feels centrifugal barrier on the way towards the black holes and eventually, shock transition is triggered…

High Energy Astrophysical Phenomena · Physics 2014-05-20 Santabrata Das , Indranil Chattopadhyay , Aunj Nandi

We examine the influence of quadrupole moment of a slowly rotating neutron star (NS) on the oscillations of a fluid accretion disk (torus) orbiting a compact object the spacetime around which is described by the Hartle-Thorne geometry.…

Black holes and weakly-magnetic accreting neutron stars show strong quasi-periodic variability over timescales that span a very wide range. This property offer us a unique opportunity to improve our understanding of basic physical processes…

Astrophysics · Physics 2009-10-31 Dimitrios Psaltis

The quasi-steady structure of super-critical accretion flows around a black hole is studied based on the two-dimensional radiation-hydrodynamical (2D-RHD) simulations. The super-critical flow is composed of two parts: the disk region and…

Astrophysics · Physics 2009-11-10 K. Ohsuga , M. Mori , T. Nakamoto , S. Mineshige

Accretion disks around compact objects are expected to enter an unstable phase at high luminosity. One instability may occur when the radiation pressure generated by accretion modifies the disk viscosity, resulting in the cyclic depletion…

We study the time evolution of a rotating, axisymmetric, viscous accretion flow around black holes using a grid based finite difference method. We use the Shakura-Sunyaev viscosity prescription. However, we compare with the results obtained…

High Energy Astrophysical Phenomena · Physics 2015-06-03 Kinsuk Giri , Sandip K. Chakrabarti

We develop a general formalism to treat, in general relativity, the nonradial oscillations of a superfluid neutron star about static (non-rotating) configurations. The matter content of these stars can, as a first approximation, be…

General Relativity and Quantum Cosmology · Physics 2009-11-07 N. Andersson , G. L. Comer , D. Langlois

We investigate the viscous two temperature accretion discs around rotating black holes. We describe the global solution of accretion flows with a sub-Keplerian angular momentum profile, by solving the underlying conservation equations…

High Energy Astrophysical Phenomena · Physics 2015-05-14 S. R. Rajesh , Banibrata Mukhopadhyay

Gravitating bodies significantly alter the flow pattern (density and velocity) of the gas that attempts to stream past. Still, small protoplanets in the Mars--super-Earth range can only bind limited amounts of nebular gas; until the…

Earth and Planetary Astrophysics · Physics 2015-06-11 C. W. Ormel

We study several Galactic black hole candidates using long-time RXTE/ASM X-ray data to search for telltale signatures of differences in viscous timescales in the two components used in the Two-Component Advective Flow (TCAF) paradigm. In…

High Energy Astrophysical Phenomena · Physics 2018-10-22 Arindam Ghosh , Sandip K. Chakrabarti

In a two component advective flow around a compact object, a high viscosity Keplerian disk is flanked by a low angular momentum and low viscosity flow which forms a centrifugal pressure supported shock wave close to the black hole. The…

High Energy Astrophysical Phenomena · Physics 2017-11-29 Santanu Mondal , Sandip K. Chakrabarti , Shreeram Nagarkoti , Patricia Arevalo

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

Accretion disks in binary systems can experience hydrodynamic impact at inner as well as outer edges. The first case is typical for protoplanetary disks around young T Tau stars. The second one is typical for circumstellar disks in close…

Solar and Stellar Astrophysics · Physics 2017-06-21 E. P. Kurbatov , D. V. Bisikalo