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Related papers: Electron Heating in Hot Accretion Flows

200 papers

It is well known that collisionless systems are dissipation free from the perspective of particle collision and thus conserve entropy. On the other hand, processes such as magnetic reconnection and turbulence appear to convert large-scale…

Plasma Physics · Physics 2020-04-01 Senbei Du , Gary P. Zank , Fan Guo , Xiaocan Li

Two significant progresses have been made in the past years on our understanding of hot accretion flows. One is that only a small fraction of accretion flow available at the outer boundary can finally falls onto the black hole while most of…

High Energy Astrophysical Phenomena · Physics 2015-06-05 Fu-Guo Xie , Feng Yuan

Space plasmas in various astrophysical setups can often be both very hot and dilute, making them highly susceptible to waves and fluctuations, which are generally self-generated and maintained by kinetic instabilities. In this sense, we…

The anisotropic diffusion of electrons with various rigidity and the anomalous conductivity of a collisionless plasma in the presence of Weibel-generated quasi-static turbulent and uniform external magnetic fields are examined. Using an…

The purpose of this paper is to explore the dynamical behaviour of hot accretion flow with thermal conduction. The importance of thermal conduction on hot accretion flow is confirmed by observations of the hot gas that surrounds Sgr A$^*$…

High Energy Astrophysical Phenomena · Physics 2012-05-11 Kazem Faghei

Recent X-ray observations of merger shocks in galaxy clusters have shown that the post-shock plasma is two-temperature, with the protons hotter than the electrons. By means of two-dimensional particle-in-cell simulations, we study the…

High Energy Astrophysical Phenomena · Physics 2017-12-27 Xinyi Guo , Lorenzo Sironi , Ramesh Narayan

The isotropization process of a collisionless plasma with an electron temperature anisotropy along an external magnetic field ($T_\| ^e\gg T_\perp^e$, $\|$ and $\perp$ with respect to the background magnetic field) and isotropic protons is…

Astrophysics · Physics 2009-11-07 Peter Messmer

An important parameter in the theory of hot accretion flows around black holes is $\delta$, which describes the fraction of ``viscously'' dissipated energy in the accretion flow that goes directly into heating electrons. For a given mass…

High Energy Astrophysical Phenomena · Physics 2023-01-11 Fu-Guo Xie , Ramesh Narayan , Feng Yuan

Black holes with accretion rates well below the Eddington rate are expected to be surrounded by low-density, hot, geometrically thick accretion disks. This includes the two black holes being imaged at sub-horizon resolution by the Event…

High Energy Astrophysical Phenomena · Physics 2017-07-26 Francois Foucart , Mani Chandra , Charles F. Gammie , Eliot Quataert , Alexander Tchekhovskoy

The magnetorotational instability (MRI) is a crucial mechanism of angular momentum transport in a variety of astrophysical accretion disks. In systems accreting at well below the Eddington rate, such as the central black hole in the Milky…

High Energy Astrophysical Phenomena · Physics 2015-06-04 Mario A. Riquelme , Eliot Quataert , Prateek Sharma , Anatoly Spitkovsky

Context. The presence of a magnetic guide field induces several types of anisotropy in solar wind turbulence. The energy cascade rate between scales in the inertial range depends strongly on the direction of this magnetic guide field,…

Plasma Physics · Physics 2022-05-18 N. Andrés , F. Sahraoui , Huang , L. Z. Hadid , S. Galtier

Strongly magnetized plasmas, characterized by having a gyrofrequency larger than the plasma frequency ($\beta = \omega_c/\omega_p \gg 1$), are known to exhibit novel transport properties. Previous works studying pure electron plasmas have…

Plasma Physics · Physics 2024-11-12 Louis Jose , James C. Welch , Timothy D. Tharp , Scott D. Baalrud

An intense transient magnetic field is produced in high energy heavy-ion collisions mostly due to the spectator protons inside the two colliding nucleus. The magnetic field introduces anisotropy in the medium and hence the isotropic scalar…

General relativistic magnetohydrodynamic (GRMHD) simulations of black hole tilted disks -- where the angular momentum of the accretion flow at large distances is misaligned with respect to the black hole spin -- commonly display standing…

High Energy Astrophysical Phenomena · Physics 2025-04-15 Lorenzo Sironi , Aaron Tran

We study wave instability in an collisionless, rarefied hot plasma (e.g. solar wind or corona). We consider the anisotropy produced by the magnetic field, when the thermal gas pressures across and along the field become unequal. We apply…

Astrophysics · Physics 2009-11-14 N. S. Dzhalilov , V. D. Kuznetsov , J. Staude

Using the transport equations for an ideal anisotropic collisionless plasma derived from the Vlasov equation by the 16-moment method, we analyse the influence of pressure anisotropy exhibited by collisionless magnetized plasmas on the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 M. S. Nakwacki , J. Peralta-Ramos

The heating of electrons in collisionless magnetic reconnection is explored in particle-in-cell (PIC) simulations with non-zero guide fields so that electrons remain magnetized. In this regime electric fields parallel to B accelerate…

Plasma Physics · Physics 2015-06-19 J. T. Dahlin , J. F. Drake , M. Swisdak

We have studied the effects of anisotropies on the momentum transport in a QCD matter by shear ($\eta$) and bulk ($\zeta$) viscosities. The anisotropies arise either by the strong magnetic field or by the preferential expansion. This study…

High Energy Physics - Phenomenology · Physics 2020-08-19 Shubhalaxmi Rath , Binoy Krishna Patra

The accretion flow around the Galactic Center black hole Sagittarius A* (Sgr A*) is expected to have an electron temperature that is distinct from the ion temperature, due to weak Coulomb coupling in the low-density plasma. We present four…

High Energy Astrophysical Phenomena · Physics 2018-05-31 Andrew Chael , Michael E. Rowan , Ramesh Narayan , Michael D. Johnson , Lorenzo Sironi

We numerically investigate the process of generating magnetic fields from temperature anisotropy of electrons in collisionless initially uniform plasmas. We use a fully kinetic modeling and compare it against a hybrid modeling which treats…

Plasma Physics · Physics 2023-05-08 A. Sladkov , A. Korzhimanov