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Related papers: On the central core in MHD winds and jets

200 papers

In this paper, we propose a general method for perturtative solutions to Blandford-Znajek mechanism. Instead of solving the nonlinear Grad-Shafranov equation directly, we introduce an alternative way to determine relevant physical…

High Energy Astrophysical Phenomena · Physics 2015-05-05 Zhen Pan , Cong Yu

Steady axisymmetric outflows originating at the hot coronal magnetosphere of a Schwarzschild black hole and surrounding accretion disk are studied in the framework of general relativistic magnetohydrodynamics (GRMHD). The assumption of…

Astrophysics · Physics 2009-11-11 Z. Meliani , C. Sauty , N. Vlahakis , K. Tsinganos , E. Trussoni

The magneto-centrifugal model for jet formation is studied by time-dependent simulations reaching steady state in a cold gas with negligible fluid pressure, in an axisymmetric geometry, using a modification of the Zeus3D code adapted to…

Astrophysics · Physics 2009-10-31 R. Krasnopolsky , Z. -Y. Li , R. D. Blandford

By a systematic method we construct general classes of exact and selfconsistent axisymmetric MHD solutions describing flows which originate at the near environment of a central gravitating astrophysical object. The unifying scheme contains…

Astrophysics · Physics 2009-10-31 N. Vlahakis , K. Tsinganos

My lecture is devoted to the analytical results available for a large class of axisymmetric stationary flows in the vicinity of compact astrophysical objects. First, the most general case is formulated corresponding to the axisymmetric…

Astrophysics · Physics 2007-05-23 V. S. Beskin

The paradigm in which magnetic fields play a crucial role in launching/collimating outflows in many astrophysical objects continues to gain support. However, semi-analytical models including the effect of magnetic fields on the dynamics and…

High Energy Astrophysical Phenomena · Physics 2017-12-13 Chiara Ceccobello , Yuri Cavecchi , Martin H. M. Heemskerk , Sera Markoff , Peter Polko , David L. Meier

We discuss the propagation of radiative MHD jets and outflows focusing on outflows driven by magneto-centrifugal rotators. Our goal is to link the properties of the jets with the physics of the sources which produce them. We find that…

Astrophysics · Physics 2007-05-23 Adam Frank , Thomas A. Gardiner , Thibaut Lery

Astrophysical jets, launched from the immediate vicinity of accreting black holes, carry away large amounts of power in a form of bulk kinetic energy of jet particles and electromagnetic flux. Here we consider a simple analytical model for…

High Energy Astrophysical Phenomena · Physics 2022-05-11 Dominika Ł. Król , Łukasz Stawarz , Mitchell C. Begelman , José-María Martí , Manel Perucho , Bohdan A. Petrenko

We investigate the internal structure of the current sheet in the pulsar wind within force-free and two-fluid MHD approximations. Within the force-free approximation we obtain general asymptotic solution of the Grad-Shafranov equation for…

High Energy Astrophysical Phenomena · Physics 2018-01-24 V. V. Prokofev , L. I. Arzamasskiy , V. S. Beskin

Using the Grad-Shafranov equation, we consider a new analytical model of the black hole magnetosphere based on the assumption that the magnetic field is radial near the horizon and uniform (cylindrical) in the jet region. Within this model,…

High Energy Astrophysical Phenomena · Physics 2013-03-12 V. S. Beskin , A. A. Zheltoukhov

(Abridged) We here investigate, by means of fully 3-D Smoothed Particle Magnetohydrodynamic numerical simulations, the effects of magnetic fields on overdense, radiatively cooling, pulsed jets, using different initial magnetic field…

Astrophysics · Physics 2009-11-06 Adriano H. Cerqueira , Elisabete M. de Gouveia Dal Pino

The core shift method is a powerful method to estimate the physical parameters in relativistic jets from active galactic nuclei. The classical approach assumes a conical geometry of a jet and a constant plasma speed. However, recent…

High Energy Astrophysical Phenomena · Physics 2024-03-06 Nokhrina E. E. , Pushkarev A. B

Diverging supersonic flows are accelerating, as in the case of a de Laval nozzle, and the same concept has been applied for acceleration of magnetohydrodynamic flows in the universe. Here, we study the dynamics of "non-diverging"…

High Energy Astrophysical Phenomena · Physics 2020-03-25 Shuta J. Tanaka , Kenji Toma

Unconfined relativistic outflows from rotating, magnetized compact objects are often well-modeled by assuming the field geometry is approximately a split-monopole at large radii. Earlier work has indicated that such an unconfined flow has…

High Energy Astrophysical Phenomena · Physics 2009-11-29 Alexander Tchekhovskoy , Jonathan C. McKinney , Ramesh Narayan

We present a relativistic-MHD numerical study of axisymmetric, magnetically driven jets with parameters applicable to gamma-ray burst (GRB) flows. We also present analytic expressions for the asymptotic jet shape and other flow parameters…

Astrophysics · Physics 2009-11-13 Serguei Komissarov , Nektarios Vlahakis , Arieh Konigl , Maxim Barkov

Observations of relativistic jets from black holes systems suggest that particle acceleration often occurs at fixed locations within the flow. These sites could be associated with critical points that allow the formation of standing shock…

High Energy Astrophysical Phenomena · Physics 2015-05-20 Peter Polko , David L. Meier , Sera Markoff

We carry out a linear stability analysis of a magnetized relativistic rotating cylindrical jet flow using the approximation of zero thermal pressure. We identify several modes of instability in the jet: Kelvin-Helmholtz, current driven and…

High Energy Astrophysical Phenomena · Physics 2019-03-13 Gianluigi Bodo , George Mamatsashvili , Paola Rossi , Andrea Mignone

We present numerical simulations of cold, axisymmetric, magnetically driven relativistic outflows. The outflows are initially sub-Alfv\'enic and Poynting flux-dominated, with total--to--rest-mass energy flux ratio up to $\mu \sim 620$. To…

Astrophysics · Physics 2009-11-13 Maxim V. Barkov , Serguei S. Komissarov

Relativistic jets in active galactic nuclei, galactic microquasars, and gamma-ray bursts are widely considered to be magnetohydrodynamically driven by black hole accretion systems, although conversion mechanism from Poynting into particle…

High Energy Astrophysical Phenomena · Physics 2016-06-21 Kenji Toma , Fumio Takahara

We have performed 3-D numerical magnetohydrodynamic (MHD) jet experiments to study the instabilities associated with strongly toroidal magnetic fields and determine if such magnetic configurations in jets are as unstable as similar…

Astrophysics · Physics 2007-05-23 F. Thomsen , A. Nordlund