Single-bunch instability of a short and dense positron beam in a photo-electron plasma is studied numerically using code LCODE. The code was originally developed for studies of plasma wakefield acceleration. It is twodimensional and fully relativistic, with both the beam and electrons modelled by macro-particles. The instability is shown to affect the rear part of the beam, right after the arri...

Presence of plasma turbulence can strongly influence propagation properties of electromagnetic signals used for surveillance and communication. In particular, we are interested in the generation of low frequency plasma turbulence in the form of coherent vortex structures coexisting with short scale density irregularities and of lower hybrid turbulence. Lower-hybrid type density irregularities a...

The two-stream instability (Buneman instability) is traditionally derived as a collisionless with the presumption that collisions inhibit this instability. We show here via combination of collisional two-fluid model and associated experimental observations made in Caltech plasma jet experiment, fact, low-frequency mode indifferent to collisions. Despite collision frequency greatly exceeding gro...

Proton beam-driven plasma wake-field acceleration has been proposed as a way to bring electrons to TeV energy range in a single plasma section. When a long proton bunch propagates into the plasma, this bunch splits into many small bunches. This phenomenon is known as a Self-Modulation Instability (SMI), and its characteristics depend on the ratio of bunch length and plasma wavelength. In this s...

A standard version of a kinetic instability for the generation of Langmuir waves by a beam of electrons is adapted to describe the analogous instability due to a beam of neutrinos. The interaction between a Langmuir wave and a neutrino is treated in the one-loop approximation to lowest order in an expansion in 1/M W in the standard electroweak model. It is shown that this kinetic instability is...

Ability to control the electric potential inside plasma is promising for various applications of E × B because trajectory particles, which meets desired purpose, mainly determined by drift motions in external and magnetic fields. In source, it well known that equilibrium states density temperature gradient can be sources instability, which, turn, affects global parameters. However, effect insta...

The cosmic large-scale structures of the Universe are mainly result gravitational instability initially small density fluctuations in dark-matter distribution. Dark matter appears to be cold and behaves as a continuous collisionless medium on cosmological scales, with evolution governed by Vlasov--Poisson equations. Cold dark can accumulate very efficiently at focused locations, leading highly ...

In plasmas with electron drift (current) relative to static ions, the ion acoustic wave is subject to the kinetic instability which takes place if the directed electron speed exceeds the ion acoustic speed. The instability threshold becomes different in the case of one quasi-neutral electron-ion plasma propagating through another static quasineutral (target) plasma. The threshold velocity of th...

It is argued that the small-scale structures observed close to the plasma tail axis of comets may be a consequence of well-known finite-resistivity instabilities in the cometary cross-tail current sheet. While the "tearing" mode instability, which causes a breakup of the layer along the current flow lines, may be responsible for the observed small condensation or "knots" near the axis, the" rip...

A low frequency instability has been observed using various electrostatic probes in a low-pressure expanding helicon plasma. The instability is associated with the presence of a current-free double layer (DL). The frequency of the instability increases linearly with the potential drop of the DL, and simultaneous measurements show their coexistence. A theory for an upstream ionization instabilit...