English
Related papers

Related papers: Particle acceleration and entropy considerations

200 papers

Particles are accelerated to very high, non-thermal energies during explosive energy-release phenomena in space, solar, and astrophysical plasma environments. While it has been established that magnetic reconnection plays an important role…

The probability that a particle, crossing the shock along a given direction, be reflected backwards along another direction, was shown to be the key element in determining the spectrum of non--thermal particles accelerated via Fermi…

Astrophysics · Physics 2007-05-23 Mario Vietri

We develop a model for stochastic acceleration of electrons in solar flares. As in several previous models, the electrons are accelerated by turbulent fast magnetosonic waves ("fast waves") via transit-time-damping (TTD) interactions. (In…

Solar and Stellar Astrophysics · Physics 2015-06-19 Peera Pongkitiwanichakul , Benjamin D. G. Chandran

Entropic force has been drawing the attention of theoretical physicists following E. Verlinde's work in 2011 to derive Newton's second law and Einstein's field equations of general relativity. In this paper, we extend the idea of entropic…

Quantum Physics · Physics 2024-12-03 Jayarshi Bhattacharya , Gautam Gangopadhyay , Sunandan Gangopadhyay

In its continuous version, the entropy functional measuring the information content of a given probability density may be plagued by a "measure" problem that results from improper weighting of phase space. This issue is addressed…

Statistical Mechanics · Physics 2011-06-08 P. Maynar , E. Trizac

The position- and momentum-space information entropies of the electron distributions of atomic clusters are calculated using a Woods-Saxon single particle potential. The same entropies are also calculated for nuclear distributions according…

Quantum Physics · Physics 2009-10-31 S. E. Massen , C. P. Panos

The present work deals with a cosmological model having particle creation mechanism in the framework of irreversible thermodynamics. In the second order non-equilibrium thermodynamical prescription, the particle creation rate is treated as…

General Relativity and Quantum Cosmology · Physics 2015-05-01 Subenoy Chakraborty , Supriya Pan , Subhajit Saha

The stochastic entropy generated during the evolution of a system interacting with an environment may be separated into three components, but only two of these have a non-negative mean. The third component of entropy production is…

Statistical Mechanics · Physics 2013-05-30 Ian J. Ford , Richard E. Spinney

We calculate the spectrum of blast wave models of gamma-ray burst sources, for various assumptions about the magnetic field density and the relativistic particle acceleration efficiency. For a range of physically plausible models we find…

Astrophysics · Physics 2011-09-30 P. Meszaros , M. J. Rees , H. Papathanassiou

Free energy and entropy are examined in detail from the standpoint of classical thermodynamics. The approach is logically based on the fact that thermodynamic work is mediated by thermal energy through the tendency for nonthermal energy to…

Physics Education · Physics 2015-06-26 Clinton D. Stoner

Space plasmas are collisionpoor and kinetic effects prevail leading to wave fluctuations, which transfer the energy to small scales: wave-particle interactions replace collisions and enhance dispersive effects heating particles and…

Solar and Stellar Astrophysics · Physics 2015-06-04 M. Lazar , V. Pierrard , S. Poedts , R. Schlickeiser

A considerable fraction of the energy in a solar flare is released as suprathermal electrons; such electrons play a major role in energy deposition in the ambient atmosphere and hence the atmospheric response to flare heating. Historically…

Solar and Stellar Astrophysics · Physics 2018-08-08 A. G. Emslie , N. H. Bian , E. P. Kontar

We study the entropy generation and particle production in scalar quantum field theory in expanding spacetimes with many-particle mixed initial states. The recently proposed coarse-grained entropy approach by Brandenberger et. al. is…

High Energy Physics - Theory · Physics 2009-10-22 Esko Keski-Vakkuri

It is argued that a typical many body energy eigenstate has a well defined thermodynamic entropy and that individual eigenstates possess thermodynamic characteristics analogous to those of generic isolated systems. We examine large systems…

Statistical Mechanics · Physics 2015-05-14 J. M. Deutsch

Non-thermal power-law distribution functions are ubiquitous in astrophysical, space, and laboratory kinetic plasmas, but their origin remains unclear. A related puzzle is the temperature inversion of the solar corona. We show that these…

Solar and Stellar Astrophysics · Physics 2026-05-07 Uddipan Banik , Amitava Bhattacharjee

This paper generalizes the entropy maximization problem leading to the Boltzmann-Gibbs distribution through the nonadditive entropy $S_{q,s}(p)=k_{s}\sum^{W}_{i\geq1}p_{i}\ln_{q}1/p_{i}$, $q\in(0,1)$, which is a rescaled version of $S_{q}$…

Mathematical Physics · Physics 2025-12-02 Leandro Lyra Braga Dognini

Internal energy, enthalpy and entropy are the key quantities to study thermodynamic properties of the moist atmosphere, because they correspond to the First (internal energy and enthalpy) and Second (entropy) Laws of thermodynamics. The aim…

Atmospheric and Oceanic Physics · Physics 2015-10-13 Pascal Marquet , Jean-François Geleyn

The density profiles and other quantities of physical interest for spherically symmetric systems are computed by assuming that a collisionless stellar gas may relax to the non-Gaussian power law distribution suggested by the nonextensive…

Astrophysics · Physics 2011-07-19 J. A. S. Lima , R. E. de Souza

We consider the possibility of a gravitationally induced particle production through the mechanism of a nonminimal curvature-matter coupling. An interesting feature of this gravitational theory is that the divergence of the energy-momentum…

General Relativity and Quantum Cosmology · Physics 2015-08-31 Tiberiu Harko , Francisco S. N. Lobo , José P. Mimoso , Diego Pavón

There is ongoing interest in the global entropy production rate as a climate diagnostic and predictor, but progress has been limited by ambiguities in its definition; different conceptual boundaries of the climate system give rise to…

Atmospheric and Oceanic Physics · Physics 2020-10-28 Goodwin Gibbins , Joanna D. Haigh