English
Related papers

Related papers: Kappa distributions: theory and applications in sp…

200 papers

In the literature different so-called $\kappa$-distribution functions are discussed to fit and model the velocity (or energy) distributions of solar wind species, pickup ions or magnetospheric particles. Here we introduce a generalized…

Solar and Stellar Astrophysics · Physics 2020-07-09 Klaus Scherer , Edin Husidic , Marian Lazar , Horst Fichtner

In the majority of the literature on plasma shock waves, electrons play the role of "ghost particles," since their contribution to mass and momentum flows is negligible, and they have been treated as only taking care of the electric plasma…

Space Physics · Physics 2015-06-22 Hans J. Fahr , John D. Richardson , Daniel Verscharen

It is shown that power law phase space distributions describe marginally stable Gibbsian equilibria far from thermal equilibrium which are expected to occur in collisionless plasmas containing fully developed quasi-stationary turbulence.…

Plasma Physics · Physics 2008-04-22 R. A. Treumann , C. H. Jaroschek

Possible entropy constraints on particle acceleration spectra are discussed. Solar flare models invoke a variety of initial distributions of the primary energy release over the particles of the flare plasma -- ie., the partition of the…

Astrophysics · Physics 2011-05-23 John C Brown , Gregory Beekman , Norman Gray , Alexander L MacKinnon

For collisionless (or collision-poor) plasma populations which are well described by the $\kappa$-distribution functions (also known as the Kappa or Lorentzian power-laws) a macroscopic interpretation has remained largely questionable,…

Computational Physics · Physics 2019-08-07 Klaus Scherer , Marian Lazar , Edin Husidic , Horst Fichtner

We study the nonextensive parameter for the rotating astrophysical systems with power-law distributions, including both the rotating self-gravitating system and the rotating space plasma. We extend the equation of nonextensive parameter to…

Statistical Mechanics · Physics 2017-02-10 Haining Yu , Jiulin Du

Non-Maxwellian distributions of particles are commonly observed in fusion studies, especially for magnetic confinement fusion plasmas. The particle distribution has a direct effect on fusion reactivity, which is the focus of this study. We…

Plasma Physics · Physics 2024-05-01 Haozhe Kong , Huasheng Xie , Bing Liu , Muzhi Tan , Di Luo , Zhi Li , Jizhong Sun

The Earth's magnetosphere represents a natural plasma laboratory that allows us to study the behavior of particle distribution functions in the absence of Coulomb collisions, typically described by the Kappa distributions. We have…

Space Physics · Physics 2021-03-24 Adetayo V. Eyelade , Marina Stepanova , Cristobal M. Espinoza , Pablo S. Moya

A non-relativistic Fokker-Planck equation for the electron distribution function is formulated incorporating the effects of stochastic acceleration by whistler-mode waves and Coulomb collisions. The stationary solution $f$ to the equation,…

Plasma Physics · Physics 2015-06-26 Chun-yu Ma , Danny Summers

This paper studies sufficient conditions for deriving the kappa distribution in polytropic plasmas by an improved method compared with the previous work [R. Guo, Phys. Plasmas \textbf{27}, 122104 (2020)]. We find that the polytropic…

Plasma Physics · Physics 2024-09-05 Ran Guo

We present a universal description of the velocity distribution function of granular gases, $f(v)$, valid for both, small and intermediate velocities where $v$ is close to the thermal velocity and also for large $v$ where the distribution…

Statistical Mechanics · Physics 2009-11-13 Thorsten Poeschel , Nikolai V. Brilliantov , Arno Formella

Efficiency of collective beam-plasma interaction strongly depends on the growth rates of dominant instabilities excited in the system. Nevertheless, exact calculations of the full unstable spectrum in the framework of relativistic kinetic…

Plasma Physics · Physics 2015-06-17 I. V. Timofeev , V. V. Annenkov

We investigate the effects of pitch-angle scattering on the efficiency of particle heating and acceleration by MHD turbulence using phenomenological estimates and simulations of non-relativistic test particles interacting with strong,…

Solar and Stellar Astrophysics · Physics 2014-03-14 Jacob W. Lynn , Eliot Quataert , Benjamin D. G. Chandran , Ian J. Parrish

By using the generalized Boltzmann equation of transport and the first-order approximation of Chapman-Enskog expansion on the kappa-distribution function, we study the thermal conductivity and Dufour effects in the weakly ionized and…

Plasma Physics · Physics 2020-03-06 Haijuan Xia , Jiulin Du

In classical thermodynamics the entropy is an extensive quantity, i.e.\ the sum of the entropies of two subsystems in equilibrium with each other is equal to the entropy of the full system consisting of the two subsystems. The extensitivity…

Plasma Physics · Physics 2018-12-05 H. Fichtner , K. Scherer , M. Lazar , H. J. Fahr , Z. Vörös

This article illustrates how very small deviations from the Maxwellian exponential tail, while leaving unchanged bulk quantities, can yield dramatic effects on fusion reaction rates and discuss several mechanisms that can cause such…

Astrophysics · Physics 2009-11-13 Marcello Lissia , Piero Quarati

The correct modelling of velocity distribution functions for particles in steady-state plasmas is a central element in the study of nuclear fusion and also in the description of space plasmas. In this work, a statistical mechanical…

Statistical Mechanics · Physics 2019-09-04 Sergio Davis , Gonzalo Avaria , Biswajit Bora , Jalaj Jain , José Moreno , Cristian Pavez , Leopoldo Soto

In this paper, we prove that the kappa distribution is the stationary solution of the Vlasov-Poisson system in an inhomogeneous plasma under the polytropic equation of state and an assumption restricting the local velocity distribution to a…

Plasma Physics · Physics 2020-12-17 Ran Guo

In heliospheric plasmas the transport of energy and particles is governed by various fluxes (e.g., heat flux) triggered by different forces, electromagnetic fields, and gradients in density or temperature. In the outer corona and at…

Solar and Stellar Astrophysics · Physics 2021-10-20 Edin Husidic , Marian Lazar , Horst Fichtner , Klaus Scherer , Stefaan Poedts

In fusion reactions, the Coulomb barrier selects particles from the high-momentum part of the distribution. Therefore, small variations of the high-momentum tail of the velocity distribution can produce strong effects on fusion rates. In…

Nuclear Theory · Physics 2009-11-11 Massimo Coraddu , Marcello Lissia , Giuseppe Mezzorani , Piero Quarati