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Related papers: Effects of Pre-ionisation in Radiative Shocks I: S…

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We performed kinetic simulations of diffusive shock acceleration in Type Ia supernova remnants (SNRs) expanding into a uniform interstellar medium (ISM). The preshock gas temperature is the primary parameter that governs the cosmic ray (CR)…

High Energy Astrophysical Phenomena · Physics 2011-05-20 Hyesung Kang

We investigated electromagnetic precursor wave emission in relativistic shocks by using two-dimensional particle-in-cell simulations. We found that the wave amplitude is significantly enhanced by a positive feedback process associated with…

High Energy Astrophysical Phenomena · Physics 2019-10-02 Masanori Iwamoto , Takanobu Amano , Masahiro Hoshino , Yosuke Matsumoto , Jacek Niemiec , Arianna Ligorini , Oleh Kobzar , Martin Pohl

We explore the physics of shock evolution and particle acceleration in non-relativistic collisionless shocks using multidimensional hybrid simulations. We analyze a wide range of physical parameters relevant to the acceleration of cosmic…

High Energy Astrophysical Phenomena · Physics 2015-05-28 L. Gargaté , A. Spitkovsky

We examine the chemical and emission properties of mildly irradiated (G0=1) magnetised shocks in diffuse media (nH=10^2 to 10^4 /cm3) at low to moderate velocities (from 3 to 40 km/s). Results: The formation of some molecules relies on…

Particle-in-cell direct simulation Monte Carlo simulations reveal that ion-acoustic instabilities excited in presheaths can cause significant ion heating. Ion-acoustic instabilities are excited by the ion flow toward a sheath when the…

Plasma Physics · Physics 2022-01-05 Lucas Beving , Matthew Hopkins , Scott Baalrud

Shock modelling predicts an electron density enhancement within the magnetic precursor of C-shocks. Previous observations of SiO, H13CO+, HN13C and H13CN toward the young L1448-mm outflow showed an over-excitation of the ion fluid that was…

High Mach number collisionless shocks are found in planetary systems and supernova remnants (SNRs). Electrons are heated at these shocks to the temperature well above the Rankine-Hugoniot prediction. However processes responsible for…

High Energy Astrophysical Phenomena · Physics 2020-11-25 Artem Bohdan , Martin Pohl , Jacek Niemiec , Paul Morris , Yosuke Matsumoto , Takanobu Amano , Masahiro Hoshino

We investigate the heating of protoplanetary disks caused by shocks associated with spiral density waves induced by an embedded planet. Using two-dimensional hydrodynamical simulations, we explore the dependence of shock heating rates on…

Earth and Planetary Astrophysics · Physics 2024-11-21 Tomohiro Ono , Tatsuki Okamura , Satoshi Okuzumi , Takayuki Muto

Our aim is to determine the dominant processes and timescales for the ionisation equilibrium of calcium under solar chromospheric conditions. The study is based on numerical simulations with the RADYN code, which includes hydrodynamics,…

Solar and Stellar Astrophysics · Physics 2015-05-27 Sven Wedemeyer-Böhm , Mats Carlsson

Astrophysical shocks at all scales, from those in the heliosphere up to the cosmological shock waves, are typically "collisionless", because the thickness of their jump region is much shorter than the collisional mean free path. Across…

The structure of relativistic radiation mediated shocks (RRMS) propagating into a cold electron-proton plasma is calculated and analyzed. A qualitative discussion of the physics of relativistic and non relativistic shocks, including order…

High Energy Astrophysical Phenomena · Physics 2010-11-17 Ran Budnik , Boaz Katz , Amir Sagiv , Eli Waxman

A two-dimensional electromagnetic particle-in-cell simulation with the realistic ion-to-electron mass ratio of 1836 is carried out to investigate the electrostatic collisionless shocks in relatively high-speed (~3000 km s^-1) plasma flows…

Plasma Physics · Physics 2010-05-12 Tsunehiko N. Kato , Hideaki Takabe

Context: Acceleration in coronal mass ejection driven shocks is currently considered the primary source of large solar energetic particle events. Aims: The solar wind, which feeds shock-accelerated particles, includes numerous ion…

Solar and Stellar Astrophysics · Physics 2013-03-19 Markus Battarbee , Timo Laitinen , Rami Vainio

We perform particle-in-cell simulations of perpendicular nonrelativistic collisionless shocks to study electron heating and pre-acceleration for parameters that permit extrapolation to the conditions at young supernova remnants. Our…

High Energy Astrophysical Phenomena · Physics 2017-10-04 Artem Bohdan , Jacek Niemiec , Oleh Kobzar , Martin Pohl

The theoretical model by Sorasio et al. (2006) for the steady state Mach number of electrostatic shocks formed in the interaction of two plasma slabs of arbitrary density and temperature is generalized for relativistic electron and…

Plasma Physics · Physics 2013-05-08 A. Stockem , E. Boella , F. Fiuza , L. O. Silva

A one parameter expression for the single ionization cross-section of atoms by electron impact is presented. Using this expression, the agreement obtained with available experimental data for 45 elements (from ionization threshold up to 200…

Atomic Physics · Physics 2007-05-23 B. Tsipinyuk , A. Bekkerman , E. Kolodney

The structure of steady plane-parallel radiative shock waves propagating through the hydrogen gas undergoing partial ionization and excitation of bound atomic states is investigated in terms of the self-consistent solution of the equations…

Astrophysics · Physics 2007-05-23 Yu. A. Fadeyev , D. Gillet

Radiative cooling is an important ingredient in hydrodynamical models involving evolution of high temperature plasmas. Unfortunately, calculating an accurate cooling coefficient generally requires the solution of over a hundred differential…

Astrophysics · Physics 2009-11-06 Robert A. Benjamin , Bradford A. Benson , Donald P. Cox

This study provides a detailed analysis of fourteen distant interplanetary shocks observed by the Solar Wind Around Pluto (SWAP) instrument onboard New Horizons. These shocks were observed with a pickup ion data cadence of approximately 30…

We examine the test-particle solution for diffusive shock acceleration, based on simple models for thermal leakage injection and Alfv'enic drift. The critical injection rate, \xi_c, above which the cosmic ray (CR) pressure becomes…

High Energy Astrophysical Phenomena · Physics 2015-05-19 Hyesung Kang , Dongsu Ryu