相关论文: Statistical Analysis of High-frequency Whistler Wa…
We propose a novel electron acceleration mechanism, which we call stochastic shock drift acceleration (SSDA), that extends the standard shock drift acceleration (SDA) for low-energy electrons at a quasi-perpendicular shock to include the…
Adiabatic heating of solar wind electrons at the Earth's bow shock and its foreshock region produces transversely anisotropic hot electrons that, in turn, generate intense high-frequency whistler-mode waves. These waves are often detected…
Thermalization and heating of plasma flows at shocks result in unstable charged-particle distributions which generate a wide range of electromagnetic waves. These waves, in turn, can further accelerate and scatter energetic particles. Thus,…
Electron acceleration to non-thermal, ultra-relativistic energies (~ 10-100 TeV) is revealed by radio and X-ray observations of shocks in young supernova remnants (SNRs). The diffusive shock acceleration (DSA) mechanism is usually invoked…
The first-order Fermi acceleration of electrons requires an injection of electrons into a mildly relativistic energy range. However, the mechanism of injection has remained a puzzle both in theory and observation. We present direct evidence…
Earth's bow shock is known to produce non-thermal electrons which are generally observed as a `spike' in their flux profile. Here, in this paper, we present an analysis of electron and whistler wave properties for a quasi-perpendicular…
Electron resonant scattering by high-frequency electromagnetic whistler-mode waves has been proposed as a mechanism for solar wind electron scattering and pre-acceleration to energies that enable them to participate in shock drift…
A theory of electron injection into diffusive shock acceleration (DSA) for the generation of cosmic-ray electrons at collisionless shocks is presented. We consider a recently proposed particle acceleration mechanism called stochastic shock…
We present the first quantified measure of the rate of energy dissipated per unit volume by high frequency electromagnetic waves in the transition region of the Earth's collisionless bow shock using data from the THEMIS spacecraft. Every…
Magnetosheath jets are localized fast flows with enhanced dynamic pressure. When they supermagnetosonically compress the ambient magnetosheath plasma, a bow wave or shock can form ahead of them. Such a bow wave was recently observed to…
Radio relics associated with merging galaxy clusters indicate the acceleration of relativistic electrons in merger-driven shocks with low sonic Mach numbers ($M_{\rm s}\lesssim 3$) in the intracluster medium (ICM). Recent studies have…
We present a statistical analysis of more than two thousand bipolar electrostatic solitary waves (ESW) collected from ten quasi-perpendicular Earth's bow shock crossings by Magnetospheric Multiscale spacecraft. We developed and implemented…
Whistler-mode waves are generated within and can propagate upstream of collisionless shocks. They are known to play a role in electron thermodynamics/acceleration and, under certain conditions, are markedly observed as wave trains preceding…
Shock-generated transients, such as hot flow anomalies (HFAs), upstream of planetary bow shocks, play a critical role in electron acceleration. Using multi-mission data from NASA's Magnetospheric Multiscale (MMS) and ESA's Cluster missions,…
In the Earth's magnetosheath (MSH), several processes contribute to energy dissipation and plasma heating, one of which is wave-particle interactions between whistler waves and electrons. However, the overall impact of whistlers on electron…
Whistler waves are thought to play an essential role in the dynamics of collisionless shocks. We use the magnetospheric multiscale (MMS) spacecraft to study whistler waves around the lower hybrid frequency, upstream of 11…
Radio relics in merging galaxy clusters are widely interpreted as synchrotron emission from relativistic electrons accelerated at large-scale shocks. However, the efficiency of diffusive shock acceleration (DSA) is expected to be reduced in…
We perform a numerical-simulation study of the acceleration of electrons at shocks that propagate through a prespecified, kinematically defined turbulent magnetic field. The turbulence consists of broadband magnetic fluctuations that are…
Diffusive shock acceleration (DSA), as an acceleration process for Galactic electrons at the solar wind termination shock (TS), is investigated with a comprehensive numerical model which incorporates shock-acceleration, particle drifts and…
We develop a model for stochastic acceleration of electrons in solar flares. As in several previous models, the electrons are accelerated by turbulent fast magnetosonic waves ("fast waves") via transit-time-damping (TTD) interactions. (In…