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Bright and dark envelope solitons in negative-ion plasmas in the presence of Maxwellian electrons population

Using the Krylov–Bogoliubov–Mitropolsky (KBM) perturbation method, a nonlinear Schrodinger (NLS) equation describing the slow modulation of the wave amplitude of the ion-acoustic wave is derived for the system. We have considered a collisionless plasma consisting of two cold-ion species with different masses, concentrations, and charge states and hot-isothermal electrons. The steady state solution of the nonlinear Schrodinger (NLS) equation is also discussed, which support bright and dark envelo...

We investigate the atomic recombination of stopped muons in dense plasmas of potential μ-catalysis concern. It is shown that in addition to the usual two-body radiative μ-ion recombination R2 highlighting low excited states and moderate plasma temperature T, a novel three-body process R3 involving ion–ion correlations could deliver a contribution several order of magnitudes above R2, steadily increasing with atomic excitation and T. It thus appears possible to explore the feasibility of μ cataly...

We show how the static dielectric function and other static characteristics of dense warm charged Fermi liquids can be obtained exclusively from the system static structure factor. The non-perturbative self-consistent method of moments is employed to extend onto quantum fluids, a similar reduction stemming from the fluctuation-dissipation theorem and other exact relations for classical one-component plasmas. The results are compared to and complement the numerical data obtained recently by the p...

Compound parabolic concentrator (CPC) cone targets have been shown to produce increased MeV photons on the NIF-ARC by 10× over flat targets. Multiple x-ray frames can potentially be generated by firing the NIF-ARC's beamlets into distinct cone targets at few nanosecond relative delays. This requires that the cone targets with delayed beams are not degraded by their proximity to previous targets. One concern is that the spatial wings of a beam fired into one target can fall on neighboring targets...

A new scheme is proposed to enhance the conversion efficiency (CE) of soft x-rays (0.1–1.5 keV) generated by irradiating a double-gold-foil target using double laser pulses to collide gold plasmas. A detailed analysis of the hydrodynamic evolution of the colliding plasmas is performed by using one-dimensional radiation hydrodynamic simulations. The results show that the total soft x-ray CE can be enhanced up to 71.5% by setting the foil thickness as d1 = 0.3 μm, and this is 14.5% higher than tha...

Gyrokinetic simulations of electric current generation in ion temperature gradient driven turbulence

Gyrokinetic simulations in the collisionless limit demonstrate the physical mechanisms and the amplitude of the current driven by turbulence. Simulation results show the spatiotemporal variation of the turbulence driven current and its connection to the divergence of the Reynolds stress and the turbulence acceleration. Fine structures (a few ion Larmor radii) of the turbulence induced current are observed near the rational surfaces with the arbitrary wavelength solver of the quasi-neutrality equ...

A typical problem of the development of high-harmonic short-wavelength gyrotrons, namely, the competition between the operating wave and a parasitic fundamental-harmonic wave, is studied. A specific case of the excitation of a far-from-cutoff parasitic wave in the backward-wave oscillator regime is considered.

Observation of the solid and liquid separation after the shock propagation in a two-dimensional Yukawa solid

After the propagation of compressional shocks in a two-dimensional (2D) Yukawa solid, the structure and dynamics of the postshock region are investigated using molecular dynamical simulations. When the compressional speed is significantly higher than 0.354a0ωpd, the postshock region melts completely; however, when this compressional speed is much lower than 0.283a0ωpd, the postshock region is still in the solid state. It is found that, when the compressional speed 0.283a0ωpd≤vleft≤0.354a0ωpd, fr...

Theoretical foundations for the evanescent mode oscillator (EMO) as a high-efficiency source of millimeter-wave and terahertz radiations

Evanescent mode oscillators (EMO) are investigated as high-efficiency sources of millimeter-waves and low-frequency parts of terahertz radiation. EMO can be considered a high-efficiency version of the extended interaction oscillator (EIO) using the evanescent resonance mode (ERM) of a slow-wave structure. It has been shown quantitatively that the efficiency of the EMO is superior to that of the conventional EIO having the same periodic unit cell. The condition to have an evanescent resonant mode...

This paper presents the experimental identification of the dynamic interaction between three fluctuations excited by different thermodynamical forces in a linear plasma. The observed fluctuations are characterized as an axial symmetric mode, a drift wave, and an azimuthally symmetric potential fluctuation from the spatiotemporal structures measured with Langmuir probe arrays. The intermittent burst of the axial symmetric mode is observed by the instantaneous wave number spectrum. The energy tran...

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