Related papers: Electron shock drift acceleration at a low-Mach-nu…
We study the electron-acoustic instabilities in plasmas with two kappa-distributed electrons and stationary ions. The instabilities are driven by the relative drift between two electron components. The suprathermal effects of different…
Stochastic acceleration of electrons and protons by waves propagating parallel to the large scale magnetic fields of magnetized plasmas is studied with emphasis on the feasibility of accelerating particles from a thermal background to…
After introduction we focus on: the transport of charged particles, the acceleration of ions at shocks, and the acceleration of electrons at shocks. Chapter 2 studies the propagation of solar energetic particles(SEPs) in turbulent magnetic…
Recently, S Patil et al. have reported the existence of an enhanced operating regime when a low-pressure (5 mTorr) capacitively coupled discharge (CCP) is driven by a very high radio-frequency (60 MHz) source in the presence of a weak…
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…
Recent advances in the understanding of the properties of supernova remnant shocks have been precipitated by the Chandra and XMM X-ray Observatories, and the HESS Atmospheric Cerenkov Telescope in the TeV band. A critical problem for this…
We measure the thermal electron energization in 1D and 2D particle-in-cell (PIC) simulations of quasi-perpendicular, low-beta ($\beta_p=0.25$) collisionless ion-electron shocks with mass ratio $m_i/m_e=200$, fast Mach number…
We propose semi-analytic models for the electron momentum distribution in weak shocks that accounts for both in situ acceleration and re-acceleration through diffusive shock acceleration (DSA). In the former case, a small fraction of…
lasma instabilities excited in collisionless shocks are responsible for particle acceleration. We have investigated the particle acceleration and shock structure associated with an unmagnetized relativistic electron-positron jet propagating…
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…
A shock wave propagating perpendicularly to an ambient magnetic field accelerates particles considerably faster than in the parallel propagation regime. However, the perpendicular acceleration stops after the shock overruns a circular…
Plasma instabilities (e.g., Buneman, Weibel and other two-stream instabilities) created in collisionless shocks may be responsible for particle (electron, positron, and ion) acceleration. Using a 3-D relativistic electromagnetic particle…
The physics of collisionless shocks is a very broad topic which has been studied for more than five decades. However, there are a number of important issues which remain unresolved. The energy repartition amongst particle populations in…
Seventy crossings of the Earths bow shock by the THEMIS satellites have been used to study thermal electron heating in collisionless, quasi-perpendicular shocks. It was found that the temperature increase of thermal electrons differed from…
A kinetic model for the shock acceleration of ions in laser-produced plasmas is developed. A fraction of the warm ions are accelerated by the large amplitude monotonic potential of the double layer created due the plasma compression and…
We model the acceleration of electrons at a shock front in a relativistic blazar jet and compute the radiation they emit in a post-shock region which contains a homogeneous magnetic field. The full space, time and momentum dependence of the…
We present a study of perpendicular subcritical shocks in a collisional laboratory plasma. Shocks are produced by placing obstacles into the super-magnetosonic outflow from an inverse wire array z-pinch. We demonstrate the existence of…
Observations of synchrotron radiation across a wide range of wavelengths provide clear evidence that electrons are accelerated to relativistic energies in supernova remnants (SNRs). However, a viable mechanism for the pre-acceleration of…
We simulate, using a particle-in-cell code, the chain of acceleration processes at work during the Compton-based interaction of a dilute electron-ion plasma with an extreme-intensity, incoherent gamma-ray flux with a photon density several…
By employing a local two-fluid theory, we investigate an obliquely propagating electromagnetic instability in the lower hybrid frequency range driven by cross-field current or relative drifts between electrons and ions. The theory…