English
Related papers

Related papers: Drift effects on electromagnetic geodesic acoustic…

200 papers

A second order nonlinear equation with variable coefficients has been derived to govern the dynamics of high frequency electrostatic drift waves in an inhomogeneous magnetized plasma in a moving frame of (2 + 1) spatio-temporal dimensions.…

Plasma Physics · Physics 2025-07-15 Siba Prasad Acharya

Geodesic acoustic mode (GAM) is analyzed by using modified gyro-kinetic (MGK) equation applicable to low-frequency microinstabilities in a rotating axisymmetric plasma. Dispersion relation of GAM in the presence of arbitrary Mach number is…

Plasma Physics · Physics 2015-01-19 Haijun Ren , Jintao Cao

The GAM group velocity is estimated from the ratio of the radial free energy flux to the total free energy applying gyrokinetic and two-fluid theory. This method is much more robust than approaches that calculate the group velocity directly…

Plasma Physics · Physics 2009-10-21 Robert Hager , Klaus Hallatschek

Nonlinear self-interaction of finite amplitude energetic particle induced geodesic acoustic mode (EGAM) is investigated using nonlinear gyrokinetic theory. It is found that both zero frequency zonal flow(ZFZF) and second harmonic can be…

Plasma Physics · Physics 2017-08-02 Zhiyong Qiu , Ilija Chavdarovski , Alessandro Biancalani , Jintao Cao

Conditions required for the streaming effect and the optical-phonon transit-time resonance to take place in a compensated bulk GaN are analyzed in detail. Monte Carlo calculations of the high-frequency differential electron mobility are…

Optics · Physics 2013-02-08 G. I. Syngayivska , V. V. Korotyeyev

There are two distinct phases in the evolution of drift wave envelope in the presence of zonal flow. A long-lived standing wave phase, which we call the Caviton, and a short-lived traveling wave phase (in radial direction) we call the…

Plasma Physics · Physics 2021-03-10 Z. Y. Liu , Y. Z. Zhang , S. M. Mahajan , A. D. Liu , C. Zhou , T. Xie

The two-field equations governing fully nonlinear dynamics of the drift wave (DW) and geodesic acoustic mode (GAM) in the toroidal geometry are derived in nonlinear gyrokinetic framework. Two stages with distinctive features are identified…

Plasma Physics · Physics 2023-06-14 Ningfei Chen , Shizhao Wei , Guangyu Wei , Zhiyong Qiu

Effects of circulating energetic ions (CEIs) on the geodesic acoustic modes (GAMs) in toroidally rotating tokamaks are theoretically analyzed utilizing the hybrid kinetic-fluid model. The frequencies of GAMs in the presence of toroidal…

Plasma Physics · Physics 2014-05-07 Haijun Ren , Chao Dong , Paul K. Chu

The elementary local and global influence of geodesic field line curvature on radial dispersion of zonal modes in magnetised plasmas is analysed with a primitive drift wave turbulence model. A net radial geodesic forcing of zonal flows and…

Plasma Physics · Physics 2012-10-19 Alexander Kendl

The spatial and temporal evolution of parametrically excited geodesic acoustic mode (GAM) initial pulse is investigated both analytically and numerically. Our results show that the nonlinearly excited GAM propagates at a group velocity…

Plasma Physics · Physics 2015-06-24 Zhiyong Qiu , Liu Chen , Fulvio Zonca

Geodesic acoustic modes (GAMs) are studied by means of the gyrokinetic global particle-in-cell code ORB5. Linear electromagnetic simulations in the low electron beta limit have been performed, in order to separate acoustic and Alfv\'enic…

The high-frequency part of spectrum of electromagnetic waves propagating parallel to the external magnetic field is considered for the macroscopically motionless plasmas with the relativistic temperatures $T\sim m_{e}c^{2}$, where $m_{e}$…

Plasma Physics · Physics 2023-08-16 Pavel A. Andreev

We propose an unconventional electron gun structure in which the emitter is located on a concave cathode surface with a non-uniform electric field. Such a design violates the intuition that an emitter should place close to a uniform…

Plasma Physics · Physics 2020-02-19 Cheng-Hung Tsai , Tsun-Hsu Chang , Toshitaka Idehara , Yuusuke Yamaguchi

Geodesic acoustic modes (GAMs) are studied, for the first time, including all poloidal mode $(m)$ couplings using drift reduced fluid equations. The nearest neighbor coupling pattern, due to geodesic curvature, leads to a semi-infinite…

Plasma Physics · Physics 2015-12-21 Rameswar Singh , Ö D Gürcan , X Garbet , P Hennequin , L Vermare , P Morel , R Singh

The theory of low-frequency (in comparison with the ion cyclotron frequency), long wavelength, electrostatic drift ion-acoustic waves (IAWs) is studied in a nonuniform rotating magnetoplasma with two temperature superthermal electrons. In…

Plasma Physics · Physics 2022-03-14 A. Abdikian , M. Eghbali , A. P. Misra

By employing a local two-fluid theory, we investigate an obliquely propagating electromagnetic instability in the lower hybrid frequency range driven by cross-field current or relative drifts between electrons and ions. The theory…

Astrophysics · Physics 2007-05-23 Hantao Ji , Russell Kulsrud , William Fox , Masaaki Yamada

The nonlinear dynamics of energetic-particle (EP) driven geodesic acoustic modes (EGAM) is investigated here. A numerical analysis with the global gyrokinetic particle-in-cell code ORB5 is performed, and the results are interpreted with the…

Plasma Physics · Physics 2018-02-14 A. Biancalani , I. Chavdarovski , Z. Qiu , A. Bottino , D. Del Sarto , A. Ghizzo , O. Gurcan , P. Morel , I. Novikau

The diffraction of electromagnetic waves at the surface periodic structures accompanied by strong anomalous effects in different diffraction orders is considered in great detail for high-contrast interfaces. We restrict our discussion to…

Optics · Physics 2019-07-31 T. Rokhmanova , A. V. Kats

Oscillations of the resistance observed under electromagnetic wave excitation in the high mobility GaAs/AlGaAs 2DES are examined as a function of the radiation frequency and the power, utilizing an empirical lineshape based on exponentially…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 R G Mani , J H Smet , K von Klitzing , V Narayanamurti , W B Johnson , V Umansky

The kinetic effects of electrons are important to long wavelength magnetohydrodynamic(MHD)instabilities and short wavelength drift-Alfvenic instabilities responsible for turbulence transport in magnetized plasmas, since the non-adiabatic…

Plasma Physics · Physics 2017-02-07 J. Bao , D. Liu , Z. Lin