479 research outputs found
Effect of resonant magnetic perturbations on zonal flows and ambient turbulence
Introduction Resonant magnetic perturbations (RMPs) are used at TEXTOR, DIII-D and JET and discussed for ITER for an effective mitigation of edge localized mode
Discriminating the trapped electron modes contribution in density fluctuation spectra
Quasi-coherent (QC) modes have been reported for more than 10 years in reflectometry
fluctuations spectra in the core region of fusion plasmas. They have characteristics in-between
coherent and broadband fluctuations as they oscillate at a marked frequency but have a wide
spectrum. This work presents further evidences of the link recently established between QC
modes and the trapped electron modes (TEM) instabilities (Arnichand et al 2014 Nucl. Fusion
54 123017). In electron cyclotron resonance heated discharges of Tore Supra, an enhancement
of QC modes amplitude is observed in a region where TEM cause impurity transport and
turbulence. In JET Ohmic plasmas, QC modes disappear during density ramp-up and current
ramp-down. This is reminiscent of Tore Supra and TEXTOR observations during transitions
from the linear Ohmic confinement (LOC) to the saturated Ohmic confinement (SOC)
regimes. Evidencing TEM activity then becomes experimentally possible via analysis of
fluctuation spectra.EURATOM 63305
High-spin parity doublets in the nucleus 151 Pm
The high-spin-level structure of the nucleus 151Pm has been investigated by in-beam γ-ray spectroscopy using the 150Nd(α, p2N) 151Pm reaction. The observed enhanced E1 transitions with B(E1) of the order of 10-3 W.u. and parity doubling, both features characteristic of a reflection-asymmetric mean field, suggest an octupole deformation in 61151P
A one-dimensional lattice model for a quantum mechanical free particle
Two types of particles, A and B with their corresponding antiparticles, are
defined in a one dimensional cyclic lattice with an odd number of sites. In
each step of time evolution, each particle acts as a source for the
polarization field of the other type of particle with nonlocal action but with
an effect decreasing with the distance: A -->...\bar{B} B \bar{B} B \bar{B} ...
; B --> A \bar{A} A \bar{A} A ... . It is shown that the combined distribution
of these particles obeys the time evolution of a free particle as given by
quantum mechanics.Comment: 8 pages. Revte
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