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Related papers: Ringed accretion disks: instabilities

200 papers

(abbreviated) In this paper we derive equations describing dynamics and stationary configurations of a twisted fully relativistic thin accretion disc around a slowly rotating black hole. We find that the disc dynamics and stationary shapes…

High Energy Astrophysical Phenomena · Physics 2015-05-27 V. Zhuravlev , P. Ivanov

We study a warping instability of a geometrically thin, non-self-gravitating disk surrounding binary supermassive black holes on a circular orbit. Such a circumbinary disk is subject to not only tidal torques due to the binary gravitational…

Astrophysics of Galaxies · Physics 2015-06-19 Kimitake Hayasaki , Bong Won Sohn , Atsuo T. Okazaki , Taehyun Jung , Guangyao Zhao , Tsuguya Naito

In the light of recent results relating dynamic and thermodynamic stability of relativistic stars and black holes, we re-examine the relationship between "turning points"---i.e., extrema of thermodynamic variables along a one-parameter…

General Relativity and Quantum Cosmology · Physics 2014-01-22 Joshua S. Schiffrin , Robert M. Wald

We show that the quasi-Euclidean sections of various rotating black holes in different dimensions possess at least one non-conformal negative mode when thermodynamic instabilities are expected. The boundary conditions of fixed induced…

General Relativity and Quantum Cosmology · Physics 2010-04-14 Ricardo Monteiro , Malcolm J. Perry , Jorge E. Santos

The choked accretion model consists of a purely hydrodynamical mechanism in which, by setting an equatorial to polar density contrast, a spherically symmetric accretion flow transitions to an inflow-outflow configuration. This scenario has…

High Energy Astrophysical Phenomena · Physics 2021-01-13 Alejandro Aguayo-Ortiz , Olivier Sarbach , Emilio Tejeda

We investigate the properties and evolution of accretion tori formed after the coalescence of two compact objects. At these extreme densities and temperatures, the accreting torus is cooled mainly by neutrino emission produced primarily by…

Astrophysics · Physics 2009-06-23 Agnieszka Janiuk , Ye-Fei Yuan , Rosalba Perna , Tiziana di Matteo

We discuss the issues of stability of accretion disks that may undergo the limit-cycle oscillations due to the two main types of thermal-viscous instabilities. These are induced either by the domination of radiation pressure in the…

High Energy Astrophysical Phenomena · Physics 2013-01-01 Agnieszka Janiuk , Ranjeev Misra , Bozena Czerny , Magdalena Kunert-Bajraszewska

Motivated by black holes surrounded by accretion structures, we consider in this series static and axially symmetric black holes "perturbed" gravitationally as being encircled by a thin disc or a ring. In previous papers, we employed…

General Relativity and Quantum Cosmology · Physics 2019-11-25 L. Polcar , O. Semerák

Rotating magnetized compact objects and their accretion discs can generate strong toroidal magnetic fields driving highly magnetized plasmas into relativistic jets. Of significant concern, however, has been that a strong toroidal field in…

Astrophysics · Physics 2009-11-13 Jonathan C. McKinney , Roger D. Blandford

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…

Solutions to Einstein's field equations describing rotating fluid bodies in equilibrium permit parametric (i.e. quasi-stationary) transitions to the extreme Kerr solution (outside the horizon). This has been shown analytically for discs of…

General Relativity and Quantum Cosmology · Physics 2011-04-28 Andreas Kleinwächter , Hendrick Labranche , Reinhard Meinel

Magnetic fields surrounding spinning black holes can confine radiation and trigger superradiant instabilities. To investigate this effect, we perform the first fully-consistent linear analysis of the Ernst spacetime, an exact solution of…

General Relativity and Quantum Cosmology · Physics 2014-05-29 Richard Brito , Vitor Cardoso , Paolo Pani

We consider the bound states of the massive scalar field around a rotating black hole immersed in the asymptotically uniform magnetic field. In the regime of slow black hole rotation, the Klein-Gordon equation allows separation of…

High Energy Physics - Theory · Physics 2009-01-16 R. A. Konoplya

Different proposals for regular rotating black hole spacetimes have appeared recently in the literature. However, a rigorous analysis and proof of the regularity of this kind of spacetimes is still lacking. In this note we analyze rotating…

General Relativity and Quantum Cosmology · Physics 2023-12-13 Ramon Torres , Francesc Fayos

We revisit the Polish doughnut model of accretion disks providing a comprehensive analytical description of the Polish doughnut structure. We describe a perfect fluid circularly orbiting around a Schwarzschild black hole, source of the…

High Energy Astrophysical Phenomena · Physics 2015-03-20 D. Pugliese , G. Montani , M. G. Bernardini

We perform stability analysis of an accretion disc around a stellar mass black hole. The cooling of the accretion flow due to bremsstrahlung and synchrotron radiation processes are considered. The solutions with shock are perturbed at the…

Astrophysics · Physics 2007-05-23 Sivakumar G. Manickam

We consider black holes generically sourced by quantum matter described by regular wavefunctions. This allows for integrable effective energy densities and the removal of Cauchy horizons in spherically symmetric configurations. Moreover, we…

General Relativity and Quantum Cosmology · Physics 2023-05-31 Roberto Casadio , Andrea Giusti , Jorge Ovalle

We present results from a numerical study of the runaway instability of thick discs around black holes. This instability is an important issue for most models of cosmic gamma-ray bursts, where the central engine responsible for the initial…

Astrophysics · Physics 2008-11-26 Jose A. Font , Frederic Daigne

Analytical treatment of black hole accretion generally presumes the stability of the stationary configuration. Various authors in the past several decades demonstrated the validity of such an assumption for inviscid hydrodynamic flow.…

High Energy Astrophysical Phenomena · Physics 2014-06-17 Sankhasubhra Nag , Deepika B Ananda , Ishita Maity , Tapas K. Das

General relativistic numerical simulations of magnetized accretion flows around black holes show a disordered electromagnetic structure in the disk and corona and a highly relativistic, Poynting-dominated funnel jet in the polar regions.…

Astrophysics · Physics 2008-11-26 Jonathan C. McKinney , Ramesh Narayan
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