English
Related papers

Related papers: Particle Heating in Advection-Dominated Accretion …

200 papers

A self-similar solution for the 3D axi-symmetric radiative MHD equations, which revisits the formation and acceleration of accretion-powered jets in AGNs and microquasars, is presented. The model relies primarily on electromagnetic…

Astrophysics · Physics 2009-11-10 A. Hujeirat , R. Blandford

In situ observations of the solar wind frequently show the temperature of $\alpha$-particles (fully ionized helium), $T_\alpha$, to significantly differ from that of protons (ionized hydrogen), $T_p$. Many heating processes in the plasma…

We discuss electron acceleration and heating during collisionless magnetic reconnection by using the results of implicit kinetic simulations of Harris current sheets. We consider and compare electron dynamics in plasmas with different \beta…

Astrophysics · Physics 2009-11-07 Paolo Ricci , Giovanni Lapenta , J. U. Brackbill

Hot-cold ablative mixing plasmas are ubiquitous in astrophysical and laboratory systems, where a cold/dense plasma is roughly in pressure balance with a hot/dilute plasma. Examples include the plasma thermal quench during major disruptions…

Plasma Physics · Physics 2025-04-01 Yanzeng Zhang , Xian-Zhu Tang

We quantify the effects of electron thermal conduction on the properties of hot accretion flows, under the assumption of spherical symmetry. Electron heat conduction is important for low accretion rate systems where the electron cooling…

Astrophysics · Physics 2011-02-11 Bryan M. Johnson , Eliot Quataert

Based on theoretical arguments and quasi-stationary radiative MHD calculations, a model for an accretion-powered jet is presented. It is argued that accretion disks around BHs consist of 1) a cold, Keplerian-rotating and weakly magnetized…

Astrophysics · Physics 2009-11-07 A. Hujeirat , M. Livio , M. Camenzind , A. Burkert

The global structure of optically thin advection dominated accretion flows which are composed of two-temperature plasma around black holes is calculated. We adopt the full set of basic equations including the advective energy transport in…

Astrophysics · Physics 2009-10-30 T. Manmoto , S. Mineshige , M. Kusunose

Spherical (nonrotating) accretion flows with small-scale magnetic fields have been investigated using three-dimensional, time-dependent MHD simulations. These simulations have been designed to model high-resolution (quasi) steady accretion…

Astrophysics · Physics 2008-11-26 Igor V. Igumenshchev

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

Context. Many low-redshift active galactic nuclei harbor a supermassive black hole accreting matter at low or medium rates. At such rates, the accretion flow usually consists of a cold optically thick disk, plus a hot, low density,…

High Energy Astrophysical Phenomena · Physics 2021-05-19 Eduardo M. Gutiérrez , Florencia L. Vieyro , Gustavo E. Romero

Numerical simulations of dispersive turbulence in magnetized plasmas based on the Hall-MHD description are presented, assuming spatial variations along a unique direction making a prescribed angle with the ambient magnetic field. Main…

Earth and Planetary Astrophysics · Physics 2015-05-18 D. Laveder , L. Marradi , T. Passot , P. L. Sulem

The inward flow of matter through accretion disks is driven by MHD turbulence. Global general relativistic MHD simulations shed quantitative light on this process, revealing a number of aspects of accretion previously unrecognized. Among…

Astrophysics · Physics 2008-11-26 J. H. Krolik , J. F. Hawley

Convection-dominated accretion flows (CDAF) are expected to have a shallower density profile and a higher radiation efficiency as compared to advection-dominated accretion flows (ADAF). Both solutions have been developed to account for the…

Astrophysics · Physics 2008-11-26 Myeong-Gu Park , Jeremiah P. Ostriker

Plasma flow and acceleration in the converging-diverging magnetic field configuration, such as magnetic nozzle in electric propulsion and open magnetic mirrors for fusion applications are considered. This work analyses plasma acceleration…

Plasma Physics · Physics 2025-06-25 A. I. Smolyakov , A. Sabo , S. I. Krasheninnikov , P. N. Yushmanov

Collisionless, magnetized turbulence offers a promising framework for the generation of non-thermal high-energy particles in various astrophysical sites. Yet, the detailed mechanism that governs particle acceleration has remained subject to…

High Energy Astrophysical Phenomena · Physics 2022-08-17 Virginia Bresci , Martin Lemoine , Laurent Gremillet , Luca Comisso , Lorenzo Sironi , Camilia Demidem

Turbulence enhances fusion reactivity, enabling ignition at lower temperature. A modified Lawson-like ignition criterion is derived for inertially confined plasmas harboring turbulent kinetic energy. Remarkably, if small-scale turbulence is…

Plasma Physics · Physics 2025-07-28 Henry Fetsch , Nathaniel J. Fisch

When the accretion rate is more than a small fraction of Eddington, the inner regions of accretion disks around black holes are expected to be radiation-dominated. However, in the alpha-model, these regions are also expected to be thermally…

Astrophysics · Physics 2011-02-11 Shigenobu Hirose , Julian H. Krolik , Omer Blaes

It has been suggested that the laws of thermodynamics are violated by what we have called a convection-dominated accretion flow (or a 1/2-law accretion flow) -- an accretion flow characterized by a constant outflow of energy. We show that…

Astrophysics · Physics 2007-05-23 Andrei Gruzinov

The multi-fluid modelling of high-frequency waves in partially ionized plasmas has shown that the behavior of magnetohydrodynamics waves in the linear regime is heavily influenced by the collisional interaction between the different species…

Solar and Stellar Astrophysics · Physics 2018-04-04 David Martínez-Gómez , Roberto Soler , Jaume Terradas

Observations and numerical simulations have shown that outflows generally exist in the accretion process. We revisit the thermal equilibrium solutions of black hole accretion flows by including the role of outflows. Our study focuses on the…

High Energy Astrophysical Phenomena · Physics 2022-05-18 Wen-Biao Wu , Wei-Min Gu , Mouyuan Sun