English
Related papers

Related papers: Spectrally resolved cosmic ray hydrodynamics -- I.…

200 papers

Repeated Compton scattering of photons with thermal electrons is one of the fundamental processes at work in many astrophysical plasma. Solving the exact evolution equations is hard and one common simplification is based on Fokker-Planck…

Cosmology and Nongalactic Astrophysics · Physics 2021-08-18 Sandeep Kumar Acharya , Jens Chluba , Abir Sarkar

The Fokker-Planck equation describing the transport of energetic particles interacting with turbulence is difficult to solve analytically. Numerical solutions are of course possible but they are not always useful for applications. In the…

Solar and Stellar Astrophysics · Physics 2025-04-29 B. Klippenstein , A. Shalchi

This paper presents a comprehensive numerical framework for simulating radiation-plasma systems. The radiative transfer process spans multiple flow regimes due to varying fluid opacity across different regions, necessitating a robust…

Astrophysics of Galaxies · Physics 2025-12-24 Mingyu Quan , Kun Xu

Stochastic acceleration of charged particles due to their interactions with plasma waves may be responsible for producing superthermal particles in a variety of astrophysical systems. This process can be described as a diffusion process in…

High Energy Astrophysical Phenomena · Physics 2012-04-05 Zhonghui Fan , Siming Liu

A numerical method based on smoothed particle hydrodynamics with adaptive spatial resolution (SPH-ASR) was developed for simulating free surface flows. This method can reduce the computational demands while maintaining the numerical…

Computational Physics · Physics 2021-07-28 Xiufeng Yang , Song-Charng Kong , Moubin Liu , Qingquan Liu

Cosmic ray (CR) transport and acceleration is essential for many astrophysical problems, e.g., CMB foreground, ionization of molecular clouds and all high energy phenomena. Recent advances in MHD turbulence call for revisions in the…

High Energy Astrophysical Phenomena · Physics 2011-12-06 Huirong Yan , A. Lazarian

The theory of diffusive particle acceleration explains the spectral properties of the cosmic rays below energies of approx. 10^6 GeV as produced at strong shocks in supernova remnants (SNR's). To supply the observed flux of cosmic rays, a…

Astrophysics · Physics 2007-05-23 U. D. J. Gieseler , T. W. Jones , Hyesung Kang

In this study, we generalize the Fokker-Planck equation to two-dimensional cases, including potential functions with periodic boundary conditions and piecewise-defined structures, to analyze the probability distribution in multi-field…

General Relativity and Quantum Cosmology · Physics 2024-04-17 Deog Ki Hong , Jie Jiang , Dong-han Yeom

The design and optimization of photobioreactors (PBR) can benefit from the development of robust and yet quantitatively accurate computational models, that incorporate the complex interplay of fundamental phenomena. At a minimum, the…

We present a numerical algorithm for the incorporation of the active cosmic ray transport, into the ZEUS-3D magnetohydrodynamical code. The cosmic ray transport is described by the diffusion-advection equation. The applied form of the…

Astrophysics · Physics 2009-11-10 M. Hanasz , H. Lesch

The new scheme of stochastic quantization is proposed. This quantization procedure is equivalent to the deformation of an algebra of observables in the manner of deformation quantization with an imaginary deformation parameter (the Planck…

High Energy Physics - Theory · Physics 2007-06-13 P. O. Kazinski

Collisionless plasma shocks are efficient sources of non-thermal particle acceleration in space and astrophysical systems. We use hybrid (kinetic ions -- fluid electrons) simulations to examine the non-linear feedback of the self-generated…

High Energy Astrophysical Phenomena · Physics 2020-12-16 Colby C. Haggerty , Damiano Caprioli

Solving the Fokker-Planck equation for high-dimensional complex turbulent dynamical systems is an important and practical issue. However, most traditional methods suffer from the curse of dimensionality and have difficulties in capturing…

Methodology · Statistics 2017-12-06 Nan Chen , Andrew J. Majda

Cosmic rays (CRs) are an integral component of the interstellar medium, producing broadband emission while interacting with other Galactic matter components like the interstellar gas or magnetic fields. In addition to observations,…

High Energy Astrophysical Phenomena · Physics 2022-10-12 Julia Thaler , Ralf Kissmann , Olaf Reimer

The cosmic ray energy distributions contain spectral features, that is narrow energy regions where the slope of the spectrum changes rapidly. The identification and study of these features is of great importance to understand the…

High Energy Astrophysical Phenomena · Physics 2017-12-27 Paolo Lipari

Entering a new era of high-energy gamma-ray experiments, there is an exciting quest for the first detection of gamma-ray emission from clusters of galaxies. To complement these observational efforts, we use high-resolution simulations of a…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Anders Pinzke , Christoph Pfrommer

The analytical theory of diffusive cosmic ray acceleration at parallel stationary shock waves with magnetostatic turbulence is generalized to arbitrary shock speeds $V_s=\beta_1c$, including in particular relativistic speeds. This is…

High Energy Astrophysical Phenomena · Physics 2015-08-19 Reinhard Schlickeiser

We consider the propagation of galactic cosmic rays in the fractal interstellar medium. Steady state solution of the fractional diffusion equation, describing cosmic ray propagation, is found. We show that the exponent of the steady state…

Astrophysics · Physics 2007-05-23 A. A. Lagutin , V. V. Makarov , A. G. Tyumentsev

We have developed a method of solving for multi-species chemical reaction flows in non--equilibrium and self--consistently with the hydrodynamic equations in an expanding FLRW universe. The method is based on a backward differencing scheme…

Astrophysics · Physics 2009-10-28 Peter Anninos , Yu Zhang , Tom Abel , Michael L. Norman

The Fokker-Planck Equation (FPE) is a fundamental tool for the investigation of kinematic aspects of a wide range of systems. For systems governed by the non-additive entropy $S_q$, the Plastino-Plastino Equation (PPE) is the correct…

High Energy Physics - Phenomenology · Physics 2023-09-13 Eugenio Megias , Airton Deppman , Roman Pasechnik , Constantino Tsallis