Author: Barry Hulett MaukPublisher:
ISBN:
Category : Cyclotron waves
Languages : en
Pages : 328
Book Description
Alfvén/ion Cyclotron Waves
Author: Barry Hulett MaukPublisher:
ISBN:
Category : Cyclotron waves
Languages : en
Pages : 328
Book Description
Saturation and Post-saturation Behavior of the Alfvén Ion-cyclotron Instability
Author: Niels Fujio OtaniThe Alfvén Ion-cyclotron Instability
Author: Niels Fujio OtaniAlfven-ion-cyclotron Instability in the Central Cell of TMX.
Author: Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
The central cell of TMX may require hot-ion injection. The resulting velocity-space anisotropy together with the length of the central homogeneous region raise the possibility of convective AIC instability. In this report we demonstrate that the Rosenbluth criterion of less than a thousand-fold amplitude amplification per pass can be satisfied by ion distributions which nevertheless have sufficient anisotropy to be confined within the central cell.
Alfven Cyclotron Instability and Ion Cyclotron Emission
Author: N. N. GorelenkovPublisher:
ISBN:
Category : Alpha rays
Languages : en
Pages : 23
Book Description
Alfven Cyclotron Instability and Ion Cyclotron Emission
Author: Publisher:
ISBN:
Category :
Languages : en
Pages : 24
Book Description
Two-dimensional solutions of compressional Alfven eigenmodes (CAE) are studied in the cold plasma approximation. For finite inverse aspect ratio tokamak plasmas the two-dimensional eigenmode envelope is localized at the low magnetic field side with the radial and poloidal localization on the order of a/√m and a/(fourth root of m), respectively, where m is the dominant poloidal mode number. Charged fusion product driven Alfven Cyclotron Instability (ACI) of the compressional Alfven eigenmodes provides the explanation for the ion cyclotron emission (ICE) spectrum observed in tokamak experiments. The ACI is excited by fast charged fusion products via Doppler shifted cyclotron wave-particle resonances. The ion cyclotron and electron Landau dampings and fast particle instability drive are calculated perturbatively for deuterium-deuterium (DD) and deuterium-tritium (DT) plasmas. Near the plasma edge at the low field side the velocity distribution function of charged fusion products is localized in both pitch angle and velocity. The poloidal localization of the eigenmode enhances the ACI growth rates by a factor of √m in comparison with the previous results without poloidal envelope. The thermal ion cyclotron damping determines that only modes with eigenfrequencies at multiples of the edge cyclotron frequency of the background ions can be easily excited and form an ICE spectrum similar to the experimental observations. Theoretical understanding is given for the results of TFTR DD and DT experiments with [upsilon]{sub {alpha}0}/[upsilon]{sub A} 1 and JET experiments with [upsilon]{sub {alpha}0}/[upsilon]{sub A} 1.
Proceedings of the Workshop on the Current-Driven Electrostatic Ion-Cyclotron Instability, July 9/10, 1987, Innsbruck, Austria
Author: R. SchrittwieserPublisher: World Scientific Publishing Company
ISBN:
Category : Science
Languages : en
Pages : 188
Book Description
Plasma Simulation Studies in the Ion Cyclotron Frequency Range
Author: Niels Fujio OtaniApplication of Nonlinear Constants of Motion in a Single Electromagnetic Wave to the Study of the Alfvén-ion-cyclotron Instability
Author: Excitation of Alfven Cyclotron Instability by Charged Fusion Products in Tokamaks
Author: Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
The spectrum of ion cyclotron emission (ICE) observed in tokamak experiments shows narrow peaks at multiples of the edge cyclotron frequency of background ions. A possible mechanism of ICE based on the fast Alfven Cyclotron Instability (ACI) resonantly excited by high energy charged products ([alpha]-particles or protons) is studied here. The two-dimensional ACI eigenmode structure and eigenfrequency are obtained in the large tokamak aspect ratio limit. The ACI is excited via wave-particle resonances in phase space by tapping the fast ion velocity space free energy. The instability growth rates are computed perturbatively from the perturbed fast particle distribution function, which is obtained by integrating the high frequency gyrokinetic equation along the particle orbit. Numerical examples of ACI growth rates are presented for TFTR plasmas. The fast ion distribution function is assumed to be singular in pitch angle near the plasma edge. The results are employed to understand the ICE in Deuterium-Deuterium (DD) and Deuterium-tritium (DT) tokamak experiments.