English
Related papers

Related papers: High Energy Cosmic-ray Diffusion in Molecular Clou…

200 papers

We study a quantum particle propagating through a ``quantum mechanically chaotic'' background, described by parametric random matrices with only short range spatial correlations. The particle is found to exhibit turbulent-like diffusion…

chao-dyn · Physics 2009-10-30 Dimitri Kusnezov , Aurel Bulgac , Gui Do Dang

Energetic particle transport in a finite amplitude magnetosonic and Alfvenic turbulence is considered using Monte Carlo particle simulations, which involve an integration of particle equation of motion. We show that in a low-Betha plasma…

Astrophysics · Physics 2008-02-03 G. Michalek , M. Ostrowski , R. Schlickeiser

Molecular clouds are complex magnetized structures, with variations over a broad range of length scales. Ionization in dense, shielded clumps and cores of molecular clouds is thought to be caused by charged cosmic rays (CRs). These CRs can…

Astrophysics of Galaxies · Physics 2021-07-27 Ellis R. Owen , Alvina Y. L. On , Shih-Ping Lai , Kinwah Wu

We calculate cosmic ray transport with a collisional Boltzmann Transport Equation, including E-M forces. We apply the Crank-Nicholson Method to solve this equation. At each time step, the spatial distribution of cosmic rays is applied to…

High Energy Astrophysical Phenomena · Physics 2011-10-17 Paul Rimmer , Eric Herbst

The dynamics of particle transport under the influence of localised high energy anomalies (explosions) is a complicated phenomena dependent on many physical parameters of both the particle and the medium it resides in. Here we present a…

Fluid Dynamics · Physics 2015-09-02 Timothy C. DuBois , Milan Jamriska , Alex Skvortsov

We describe a method for determining the dispersion of magnetic field vectors about large-scale fields in turbulent molecular clouds. The method is designed to avoid inaccurate estimates of magnetohydrodynamic or turbulent dispersion - and…

Recent measurements of cosmic ray proton and helium spectra show a hardening above a few hundreds of GeV. This excess is hard to understand in the framework of the conventional models of Galactic cosmic ray production and propagation. We…

High Energy Astrophysical Phenomena · Physics 2013-10-01 Guilhem Bernard , Timur Delahaye , Yong-Yeon Keum , Wei Liu , Pierre Salati , Richard Taillet

We phenomenologically developed a propagation model of high energy galactic cosmic rays. We derived the analytical solutions by adopting the semi-empirical diffusion equation, proposed by Berezinskii {\it et al.}(1990) and the diffusion…

High Energy Astrophysical Phenomena · Physics 2012-02-07 Hideyoshi Arakida , Shuichi Kuramata

Ultra-high energy cosmic rays can propagate diffusively in cosmic magnetic fields. When their propagation time is comparable to the age of the universe, a suppression in the flux relative to the case in the absence of magnetic fields will…

High Energy Astrophysical Phenomena · Physics 2014-12-10 Rafael Alves Batista , Guenter Sigl

Momentum deposition by radiation pressure from young, massive stars may help to destroy molecular clouds and unbind stellar clusters by driving large-scale outflows. We extend our previous numerical radiation hydrodynamic study of…

Astrophysics of Galaxies · Physics 2017-12-06 Sudhir Raskutti , Eve C. Ostriker , M. Aaron Skinner

Understanding how cosmic rays (CRs) propagate within the giant molecular clouds (GMCs) is critical for studying the dynamics and chemical processes inside the clouds. The flux of low-energy CRs inside the dense cores of GMCs strongly…

High Energy Astrophysical Phenomena · Physics 2024-12-03 Zhaodong Shi , Bing Liu , Rui-zhi Yang

This work investigates the evolution of the distribution of charged particles due to the mechanism of stochastic turbulent acceleration (STA) in presence of small-scale turbulence with a mean magnetic field. STA is usually modelled as a…

High Energy Astrophysical Phenomena · Physics 2023-07-19 Sayan Kundu , Nishant Singh , Bhargav Vaidya

Starburst galaxies are efficient $\gamma$-ray producers, because their high supernova rates generate copious cosmic ray (CR) protons, and their high gas densities act as thick targets off which these protons can produce neutral pions and…

High Energy Astrophysical Phenomena · Physics 2020-02-26 Mark R. Krumholz , Roland M. Crocker , Siyao Xu , A. Lazarian , M. T. Rosevear , Jasper Bedwell-Wilson

Hot accretion flows contain collisionless plasmas that are believed to be capable of accelerating particles to very high energies, as a result of turbulence generated by the magnetorotational instability (MRI). We conduct unstratified…

High Energy Astrophysical Phenomena · Physics 2021-07-14 Xiaochen Sun , Xue-Ning Bai

We consider the propagation of ultra high energy cosmic rays through turbulent magnetic fields and study the transition between the regimes of single and multiple images of point-like sources. The transition occurs at energies around…

Astrophysics · Physics 2009-11-07 Diego Harari , Silvia Mollerach , Esteban Roulet , Federico Sanchez

Cosmic rays (CRs) are a dynamically important component of the interstellar medium (ISM) of galaxies. The $\sim$GeV CRs that carry most CR energy and pressure are likely confined by self-generated turbulence, leading them to stream along…

Astrophysics of Galaxies · Physics 2022-11-16 Matt L. Sampson , James R. Beattie , Mark R. Krumholz , Roland M. Crocker , Christoph Federrath , Amit Seta

We describe a method for the numerical computation of the propagation of primary and secondary nucleons, primary electrons, and secondary positrons and electrons. Fragmentation and energy losses are computed using realistic distributions…

Astrophysics · Physics 2011-05-05 A. W. Strong , I. V. Moskalenko

Cosmic ray (CR) transport and acceleration is determined by the properties of magnetic turbulence. Recent advances in MHD turbulence call for revisions in the paradigm of cosmic ray transport. We use the models of magnetohydrodynamic…

High Energy Astrophysical Phenomena · Physics 2015-06-15 Huirong Yan

Cosmic rays up to at least PeV energies are usually described in the framework of an elementary scenario that involves acceleration by objects that are located in the disk of the Milky Way, such as supernova remnants or massive star-forming…

High Energy Astrophysical Phenomena · Physics 2019-08-14 L. Tibaldo , S. W. Digel

The propagation of Galactic Cosmic Ray nuclei having energies between 100 MeV/nuc and several PeV/nuc is strongly believed to be of diffusive nature. The particles emitted by a source located in the disk do not pervade the whole Galaxy, but…

Astrophysics · Physics 2009-11-07 Richard Taillet , David Maurin
‹ Prev 1 4 5 6 7 8 10 Next ›