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

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We analyze the main features of radiation-mediated shocks at arbitrary shock velocities, both non-relativistic and relativistic. We describe two mechanisms, which may lead to formation of a sharp viscous subshock within otherwise smooth…

High Energy Astrophysical Phenomena · Physics 2018-12-27 Evgeny Derishev

A novel diagnostic of cosmic-ray modified shocks by polarimetry of H $\alpha$ emissions is suggested. In a cosmic-ray modified shock, the pressure of cosmic rays is sufficiently high compared to the upstream ram pressure to force the…

High Energy Astrophysical Phenomena · Physics 2019-09-25 Jiro Shimoda , J. Martin Laming

The efficiency of particle acceleration at shock waves in relativistic, magnetized astrophysical outflows is a debated topic with far-reaching implications. Here, for the first time, we study the impact of turbulence in the pre-shock…

High Energy Astrophysical Phenomena · Physics 2023-07-06 Virginia Bresci , Martin Lemoine , Laurent Gremillet

We investigate the observability, by direct and indirect means, of a shock precursor arising from magnetic field amplification by cosmic rays. We estimate the depth of such a precursor under conditions of nonresonant amplification, which…

High Energy Astrophysical Phenomena · Physics 2015-06-19 J. Martin Laming , Una Hwang , Parviz Ghavamian , Cara Rakowski

We model a one-dimensional shock-tube using smoothed particle hydrodynamics and investigate the consequences of having finite shock-width in numerical simulations. We investigate the cooling of gas during passage through the shock for…

Astrophysics · Physics 2009-10-31 Roger M. Hutchings , Peter A. Thomas

Collisionless shocks heat electrons in the solar wind, interstellar blast waves, and hot gas permeating galaxy clusters. How much shock heating goes to electrons instead of ions, and what plasma physics controls electron heating? We…

Space Physics · Physics 2021-01-01 Aaron Tran , Lorenzo Sironi

We have performed an extensive statistical investigation of how interplanetary fast forward shocks affect certain turbulence parameters, namely, the cross-helicity, $\sigma_c$, residual energy, $\sigma_r$, and magnetic helicity, $\sigma_m$.…

Solar and Stellar Astrophysics · Physics 2025-05-09 Emilia Kilpua , Simon Good , Juska Soljento , Domenico Trotta , Tia Bäcker , Julia Ruohotie , Jens Pomoell , Chaitanya Sishtla , Rami Vainio

Collisionless relativistic shocks have been the focus of intense theoretical and numerical investigations in recent years. The acceleration of particles, the generation of electromagnetic microturbulence and the building up of a shock front…

High Energy Astrophysical Phenomena · Physics 2015-06-05 Illya Plotnikov , Guy Pelletier , Martin Lemoine

We present time-dependent 1D simulations of multifluid magnetic shocks with chemistry resolved down to the mean free path. They are obtained with an adaptive moving grid implemented with an implicit scheme. We examine a broad range of…

Astrophysics · Physics 2009-11-10 P. Lesaffre , J. -P. Chièze , S. Cabrit , G. Pineau des Forêts

Collisionless shocks are known to induce turbulence via upstream ion reflection within the precursor region. This study elucidates the properties of electrostatic and electromagnetic instabilities, exploring their role over the…

Plasma Physics · Physics 2024-09-10 Théo Abounnasr

We investigate shock structure and particle acceleration in relativistic magnetized collisionless electron-ion shocks by means of 2.5D particle-in-cell simulations with ion-to-electron mass ratios (m_i/m_e) ranging from 16 to 1000. We…

High Energy Astrophysical Phenomena · Physics 2015-05-19 Lorenzo Sironi , Anatoly Spitkovsky

We examine the structure of the post-shock region in supernova remnants (SNRs). The ``shock transition zone'' is set up by charge transfer and ionization events between atoms and ions, and has a width $\sim 10^{15}$ cm$^{-2}$ $n^{-1}_0$,…

Astrophysics · Physics 2009-11-13 Kevin Heng , Matthew van Adelsberg , Richard McCray , John C. Raymond

Thermal instabilities can cause a radiative shock to oscillate, thereby modulating the emission from the post-shock region. The mode frequencies are approximately quantised in analogy to those of a vibrating pipe. The stability properties…

Astrophysics · Physics 2009-11-07 Curtis J. Saxton

X-ray observations of protostellar jets show evidence of strong shocks heating the plasma up to temperatures of a few million degrees. In some cases, the shocked features appear to be stationary. They are interpreted as shock diamonds. We…

Solar and Stellar Astrophysics · Physics 2016-12-14 S. Ustamujic , S. Orlando , R. Bonito , M. Miceli , A. I. Gómez de Castro , J. López-Santiago

Higher order parameters in the hard disk fluid are computed to investigate the number, the life time and size of transient crystal nuclei in the pre-freezing phase. The methodology introduces further neighbor shells bond orientational order…

Statistical Mechanics · Physics 2012-11-22 Masaharu Isobe , Berni J. Alder

The role of slow-mode MHD shocks in magnetic reconnection is one of great importance for energy conversion and transport, but in many astrophysical plasmas the plasma is not fully ionised. In this paper, we investigate, using numerical…

Solar and Stellar Astrophysics · Physics 2016-10-27 Andrew Hillier , Shinsuke Takasao , Naoki Nakamura

Interplanetary shocks are one of the proposed sources of suprathermal ion populations (i.e., ions with energies of a few times the solar wind energy). Here, we present results from a series of three-dimensional hybrid simulations of…

Space Physics · Physics 2020-07-15 Matthew A. Young , Bernard J. Vasquez , Harald Kucharek , Noé Lugaz

Spatial and spectral profiles of O VI emission behind a shock wave on the northern edge of the Cygnus Loop were obtained with the FUSE satellite. The velocity width of the narrowest O VI profile places a tight constraint on the electron-ion…

Astrophysics · Physics 2009-11-07 John Raymond , Parviz Ghavamian , Ravi Sankrit , William Blair , Salvador Curiel

Collisionless shocks are efficient particle accelerators. At Earth, ions with energies exceeding 100 keV are seen upstream of the bow shock when the magnetic geometry is quasi-parallel, and large-scale supernova remnant shocks can…

High Energy Astrophysical Phenomena · Physics 2016-03-23 Torbjörn Sundberg , Christopher T. Haynes , David Burgess , Christian X. Mazelle

We perform particle-in-cell simulations to elucidate the microphysics of relativistic weakly magnetized shocks loaded with electron-positron pairs. Various external magnetizations $\sigma\lesssim 10^{-4}$ and pair-loading factors $Z_\pm…

High Energy Astrophysical Phenomena · Physics 2022-07-07 Daniel Groselj , Lorenzo Sironi , Andrei M. Beloborodov