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Related papers: Electron Heating in Hot Accretion Flows

200 papers

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

We present a model of optically thin, two-temperature, accretion flows using an exact Monte Carlo treatment of global Comptonization, with seed photons from synchrotron and bremsstrahlung emission, as well as with a fully general…

High Energy Astrophysical Phenomena · Physics 2015-05-28 A. Niedzwiecki , F. -G. Xie , A. A. Zdziarski

The ASACUSA collaboration produces a beam of antihydrogen atoms by mixing pure positron and antiproton plasmas in a strong magnetic field with a double cusp geometry. The positrons cool via cyclotron radiation inside the cryogenic trap. Low…

We numerically explore electron acceleration and coronal heating by dissipative electric fields. Electrons are traced in linear force-free magnetic fields extrapolated from SOHO/MDI magnetograms, endowed with anomalous resistivity ($\eta$)…

Astrophysics · Physics 2009-11-11 Kaspar Arzner , Loukas Vlahos

A model for axisymmetric magnetized accretion flow is proposed. The dominant mechanism of energy dissipation is assumed to be the magnetic diffusivity due to turbulence in the accretion flow. In analogy to the advection-dominated accretion…

Astrophysics · Physics 2009-11-07 Mohsen Shadmehri

The new in situ measurements of the Solar Orbiter mission contribute to the knowledge of the suprathermal populations in the solar wind, especially of ions and protons whose characterization, although still in the early phase, seems to…

Solar and Stellar Astrophysics · Physics 2024-09-17 S. M. Shaaban , R. A. Lopez , M. Lazar , S. Poedts

In a hot, dilute, magnetized accretion flow, the electron mean-free path can be much greater than the Larmor radius, thus thermal conduction is anisotropic and along magnetic field lines. In this case, if the temperature decreases outward,…

High Energy Astrophysical Phenomena · Physics 2015-05-20 De-Fu Bu , Feng Yuan , James M Stone

Given the large anisotropy of transport processes in magnetized plasmas, the magnetic field structure can strongly impact heat diffusion: magnetic surfaces and cantori form barriers to transport while chaotic layers and island structures…

Plasma Physics · Physics 2022-02-08 Elizabeth J. Paul , Stuart R. Hudson , Per Helander

The dynamics of weakly magnetized collisionless plasmas in the presence of an imposed temperature gradient along an ambient magnetic field is explored with particle-in-cell simulations and modeling. Two thermal reservoirs at different…

High Energy Astrophysical Phenomena · Physics 2018-01-22 G. T. Roberg-Clark , J. F. Drake , C. S. Reynolds , M. Swisdak

We have studied how the transport of charge and heat as well as associated observables become influenced by a weak-momentum anisotropy arising due to the asymptotic expansion of baryon asymmetric matter in the initial stages of heavy ion…

High Energy Physics - Phenomenology · Physics 2026-03-20 Shubhalaxmi Rath

In 1959 Weibel demonstrated that when a QED plasma has a temperature anisotropy there exist unstable transverse magnetic excitations which grow exponentially fast. In this paper we will review how to determine the growth rates for these…

High Energy Physics - Phenomenology · Physics 2017-08-23 Paul Romatschke , Michael Strickland

Early in the study of viscous accretion disks it was realized that energy transfers from distant sources must be important, not least because the flow at the disk midplane in the bulk of the disk is likely outwards, out of the gravitational…

Earth and Planetary Astrophysics · Physics 2014-12-15 Alexander Hubbard , Colin P. McNally , Jeffrey S. Oishi , Wladimir Lyra , Mordecai-Mark Mac Low

Turbulence is often invoked to explain the origin of nonthermal particles in space and astrophysical plasmas. By means of 3D fully kinetic particle-in-cell simulations, we demonstrate that turbulence in low-$\beta$ plasmas ($\beta$ is the…

High Energy Astrophysical Phenomena · Physics 2022-09-16 Luca Comisso , Lorenzo Sironi

We calculate the amount of angular momentum that thermal photons carry out of a viscous black hole accretion disc, due to the strong Doppler shift imparted to them by the high orbital velocity of the radiating disc material. While the…

High Energy Astrophysical Phenomena · Physics 2015-05-20 Jarrett L. Johnson

We report on the fourth phase of our study of slightly rotating accretion flows onto black holes. The main new element of this study is that we used fully three dimensional (3-D) numerical simulations. We consider hydrodynamics of inviscid…

Astrophysics · Physics 2009-11-13 Agnieszka Janiuk , Daniel Proga , Ryuichi Kurosawa

We study radiative properties of hot accretion flows in a general relativistic model with an exact treatment of global Comptonization, developed in our recent works. We note a strong dependence of electron temperature on the strength of…

High Energy Astrophysical Phenomena · Physics 2015-06-22 Andrzej Niedzwiecki , Fu-Guo Xie , Agnieszka Stepnik

The high energy continuum in Seyfert galaxies and galactic black hole candidates is likely to be produced by a thermal plasma. There are difficulties in understanding what can keep the plasma thermal, especially during fast variations of…

Astrophysics · Physics 2009-10-30 G. Ghisellini , F. Haardt , R. Svensson

We present numerical simulations of properties of a parsec-scale torus exposed to illumination by the central black hole in an active galaxy (AGN). Our physical model allows to investigate the balance between the formation of winds and…

Astrophysics of Galaxies · Physics 2016-03-23 Anton Dorodnitsyn , Tim Kallman , Daniel Proga

In the core-accretion formation scenario of gas giants, most of the gas accreting onto a planet is processed through an accretion shock. In this series of papers we study this shock since it is key in setting the forming planet's structure…

Earth and Planetary Astrophysics · Physics 2019-09-04 Gabriel-Dominique Marleau , Christoph Mordasini , Rolf Kuiper

Radiatively inefficient accretion flows (RIAFs) are common feature of low-luminosity accretion flows, including quiescent states of X-ray binaries and low-lunimosity active galactic nuclei. Thermally driven winds are expected from such hot…

High Energy Astrophysical Phenomena · Physics 2015-05-13 Ryoji Kawabata , Shin Mineshige