Electron holes and their role in the dynamics of current-carrying weakly collisional plasmas. Part 2. Mobile ions

1996 ◽  
Vol 56 (2) ◽  
pp. 339-359 ◽  
Author(s):  
J. Korn ◽  
H. Schamel
Keyword(s):  
Ion Mobility ◽  
Electron Distribution ◽  
Electron Distribution Function ◽  
Parallel Transport ◽  
Dynamical Evolution ◽  
Thermal Range ◽  
Electron Holes ◽  
Mobile Ions ◽  
A Current

New dissipative structural equilibria of the Vlasov-Fokker-Planck-Poisson system in a current-carrying plasma with mobile ions are presented. The dynamical evolution towards these final equilibrium states is explored. First consequences for the parallel transport are derived and it is shown that the anomalous resistivity depends on non-symmetric distortions of the electron distribution function in the thermal range which are affected by collisions and ion mobility. The fundamental role of electron holes as the underlying collisionless structure is emphasized.

scholarly journals Radiation in the neighbourhood of a double layer

2014 ◽  
Vol 32 (6) ◽  
pp. 677-687 ◽  
Author(s):  
R. Pottelette ◽  
M. Berthomier ◽  
J. Pickett
Keyword(s):  
Phase Space ◽  
Electron Distribution ◽  
Electron Distribution Function ◽  
Source Region ◽  
Double Layers ◽  
Small Scale ◽  
High Time Resolution ◽  
Local Electron ◽  
Nonlinear Phase ◽  
Electron Holes

Abstract. In the auroral kilometric radiation (AKR) source region, acceleration layers narrow in altitude and associated with parallel field-aligned potential drops of several kV can be identified by using both particles and wave-field high time-resolution measurements from the Fast Auroral SnapshoT explorer spacecraft (FAST). These so-called double layers (DLs) are recorded around density enhancements in the auroral cavity, where the enhancement can be at the edge of the cavity or even within the cavity at a small scale. Once immersed in the plasma, DLs necessarily accelerate particles along the magnetic field lines, thereby generating locally strong turbulent processes leading to the formation of nonlinear phase space holes. The FAST data reveal the asymmetric character of the turbulence: the regions located on the high-potential side of the DLs are characterized by the presence of electron holes, while on the low-potential side, ion holes are recorded. The existence of these nonlinear phase space holes may affect the AKR radiation pattern in the neighbourhood of a DL where the electron distribution function is drastically different from a horseshoe shape. We present some observations which illustrate the systematic generation of elementary radiation events occurring significantly above the local electron gyrofrequency in the presence of electron holes. These fine-scale AKR radiators are associated with a local electron distribution which presents a pronounced beam-like shape.

Analytical model for collisionless scrape-off-layer plasma during disruptions and enhanced phase of normal operation

2000 ◽  
Vol 63 (4) ◽  
pp. 355-369 ◽  
Author(s):  
A. HASSANEIN ◽  
I. K. KONKASHBAEV
Keyword(s):  
Electron Distribution ◽  
Electron Distribution Function ◽  
Planck Equation ◽  
Edge Plasma ◽  
Normal Operation ◽  
Divertor Plate ◽  
Numerical Studies ◽  
Wide Range ◽  
Good Agreement

The structure of a collisionless scrape-off-layer (SOL) plasma in tokamak reactors is studied in order to define the electron distribution function and the corresponding sheath potential between the divertor plate and the edge plasma. The collisionless model is shown to be valid during the thermal phase of plasma disruption, as well as during the newly desired low-recycling normal phase of operation with low-density, high-temperature, edge plasma conditions. An analytical solution is developed by solving the Fokker–Planck equation for electron distribution and balance in the SOL. The solution is in good agreement with numerical studies using Monte Carlo methods. The analytical solutions provide insight into the role of different physical and geometrical processes in a collisionless SOL during disruptions and during the enhanced phase of normal operation over a wide range of parameters.

Role of Regulatory Acts in Creation of a Democratic State

2020 ◽  
pp. 82-86
Author(s):  
R. F.o. Veliev
Keyword(s):  
Russian Federation ◽  
Legal Norm ◽  
Legal Basis ◽  
Democratic State ◽  
The Russian Federation ◽  
A Current

A current theoretical and practical legal basis for creation of regulatory acts in the Russian Federation is discussed. A current relationship between the issued regulatory acts and some criteria of legal norm classification is shown. Legalization of the President address to the Parliament of the Russian Federation as a substantial element of the legal norm-making in a democratic state is revealed.

Audit Reviewers' Judgments in Multiple Client Audit Environments

2017 ◽  
Vol 29 (2) ◽  
pp. 1-9 ◽  
Author(s):  
Sudip Bhattacharjee ◽  
Mario J. Maletta ◽  
Kimberly K. Moreno
Keyword(s):  
Audit Quality ◽  
Internal Audit ◽  
Contrast Effects ◽  
Comparative Information ◽  
A Current

ABSTRACT This study replicates Bhattacharjee, Maletta, and Moreno (2007), who find that audit preparers are susceptible to contrast effects in a multi-client environment. We demonstrate that auditors in the role of reviewers are also susceptible to contrast effects from a prior client. Audit reviewers' assessments of internal audit quality of a current client were significantly affected by the quality of the internal audit group of a client they previously reviewed. Specifically, when auditors first reviewed a client with a weak internal audit group they assessed the subsequent moderate internal audit group as being of higher quality than when they first reviewed a prior client with a strong internal audit group or did not review a prior client. Reviewers' documentation of evidence was also influenced by comparative information from the prior client. These results corroborate the key findings of Bhattacharjee et al. (2007) and confirm audit reviewers' susceptibility to contrast effects.

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