Related papers: On-surface potential and radial electric field var…
First observations of electrostatic potential variations within the flux surfaces of a toroidal magnetic confinement device are presented. Measurements are taken in the TJ-II stellarator with two distant Langmuir probe arrays. The edge…
In this work we present the first measurements obtained by the V-band Doppler reflectometer during the second operation phase of Wendelstein 7-X to discuss the influence in the velocity shear layer and the radial electric field, E$_r$, of…
The particle transport of impurities in magnetically confined plasmas under some conditions does not find, neither quantitatively nor qualitatively, a satisfactory theory-based explanation. This compromise the successful realization of…
Radial profiles of density fluctuations and radial electric field, $E_r$, have been measured using Doppler reflectometry during the post-pellet enhanced confinement phase achieved, under different heating power levels and magnetic…
The drift kinetic equation is solved for low density TJ-II plasmas employing slowly varying, time-dependent profiles. This allows to simulate density ramp-up experiments and to describe from first principles the formation and physics of the…
The formation of the radial electric field, $E_{\rm r}$ in the SOL has been experimentally studied for attached divertor conditions in stellarator W7-X. The main objective of this study is to test the validity in a complex 3D island…
Calculations of the monoenergetic radial diffusion coefficients are presented for several configurations of the TJ-II stellarator usually explored in operation. The neoclassical radial fluxes and the ambipolar electric field for the…
Good fast-ion confinement is an essential requirement for a fusion reactor. The magnetic configuration of the Wendelstein 7-X (W7-X) stellarator is partially optimized in this regard in a reactor-relevant scenario: it is expected to show…
We draw attention to an interesting possibility in the design and operation of stellarator fusion reactors, which has hitherto been considered unrealistic under burning-plasma conditions. Thanks to recent advances in stellarator…
Electric field measurement in plasmas permits quantitative comparison between the experiment and the simulation in this study. An electro-optic (EO) sensor based on Pockels effect is demonstrated to measure wave electric fields in the…
Measurements of the relaxation of a zonal electrostatic potential perturbation in a non-axisymmetric magnetically confined plasma are presented. A sudden perturbation of the plasma equilibrium is induced by the injection of a cryogenic…
Plasma current filamentation of an ultrarelativistic electron beam impinging on an overdense plasma is investigated, with emphasis on radiation-induced electron polarization. Particle-in-cell simulations provide the classification and…
The effects of a radiation field (RF) on the interaction process of a relativistic electron beam (REB) with an electron plasma are investigated. The stopping power of the test electron averaged with a period of the RF has been calculated…
The condition and specific features of non-dipole regime of radiation is discussed in connection with the results of recent CERN experiment NA63 on measurement of radiation power spectrum of $149\,$GeV electrons in thin tantalum targets.…
Low-collisionality stellarator plasmas usually display a large negative radial electric field that has been expected to cause accumulation of impurities due to their high charge number. In this paper, two combined effects that can…
Numerical models of solar flares typically focus on the behaviour of directly-heated flare models, adopting magnetic field- aligned, plane-parallel methodologies. With high spatial- and spectral-resolution ground-based optical observations…
Faraday rotation measures (RMs) of the polarized emission from extragalactic radio sources occulted by the coronal plasma were used to infer the radial profile of the inner heliospheric magnetic field near solar minimum activity. By…
We propose a self-consistent model which utilizes the polarization vector to theoretically describe the evolution of spin polarization of relativistic electrons in an intense electromagnetic field. The variation of radiative polarization…
We consider an exterior electromagnetic field surrounding a rotating star endowed with a dipole magnetic field in the context of general relativity. The analytic solution for a stationary configuration is obtained, and the general…
We present evidence supporting wave reflection in the lower solar chromosphere based on helioseismic analysis of multi-height Doppler data. This evidence is derived through a wave propagation model that incorporates both upward- and…