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Related papers: Gyrokinetic Studies of Microinstabilities in the R…

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The gradient-driven microturbulence in ADITYA-U tokamak plasmas has been suppressed by injecting short gas puffs. The suppression of microturbulence increases the core temperature and subsequently the energy confinement time following the…

The effect of magnetic shear and shear flow on local gravitationally induced instabilities is investigated. A simple model is constructed allowing for an arbitrary entropy gradient and a shear plasma flow in the Boussinesq approximation. A…

Astrophysics · Physics 2009-11-06 Gregory G. Howes , Steven C. Cowley , James C. McWilliams

In the past years we have experienced an increasing interest in understanding of the physical properties of collisionless plasmas, mostly because of the large number of astrophysical environments, e.g. the intracluster medium (ICM),…

Astrophysics of Galaxies · Physics 2015-05-20 Grzegorz Kowal , D. A. Falceta-Goncalves , A. Lazarian

Impacts of isotope ion mass on trapped electron mode (TEM) driven turbulence and zonal flows in magnetically confined fusion plasmas are investigated. Gyrokinetic simulations of TEM-driven turbulence in three-dimensional magnetic…

Plasma Physics · Physics 2026-02-27 Motoki Nakata , Masanori Nunami , Hideo Sugama , Tomo-Hiko Watanabe

Effects of anisotropy on the geodesic acoustic mode (GAM) is analyzed by using gyro-kinetic equations applicable to low-frequency microinstabilities in a toroidally rotating tokamak plasma. Dispersion relation in the presence of arbitrary…

Plasma Physics · Physics 2015-03-05 Haijun Ren

Nonlinear multiscale gyrokinetic simulations of a Joint European Torus edge pedestal are used to show that electron-temperature-gradient (ETG) turbulence has a rich three-dimensional structure, varying strongly according to the local…

Balanced double-null configurations are of general interest for boundary plasma physics, and they have been proposed for some future designs. Experimental observations demonstrate absence of plasma fluctuations in tokamak high-field side…

Plasma Physics · Physics 2024-10-11 Maxim V. Umansky

Gyrokinetic simulations conducted by Mazzi et al. reveal the suppression of turbulence in fusion plasmas through the destabilization of Toroidal Alfv\'en Eigenmodes (TAEs) by megaelectronvolt ions. Our analysis demonstrates that the…

Understanding the multi-scale neoclassical and turbulence physics in the edge region (pedestal + scrape-off layer) is required in order to reliably predict performance in future fusion devices. We explore turbulent characteristics in the…

Plasma Physics · Physics 2017-09-13 R. M. Churchill , C. S. Chang , S. Ku

Traditionally the effects of MHD instabilities and micro-instabilities on plasma confinement are investigated separately. However, these two instabilities often occur simultaneously, with the overlap of the dynamics on a broad range of…

Plasma Physics · Physics 2009-07-06 Johan Anderson , Eun-jin Kim

Magnetohydrodynamic (MHD) turbulence is encountered in a wide variety of astrophysical plasmas, including accretion disks, the solar wind, and the interstellar and intracluster medium. On small scales, this turbulence is often expected to…

Spherical tokamaks (STs) have many desirable features that make them an attractive choice for a future fusion power plant. Power plant viability is intrinsically related to plasma heat and particle confinement and this is often determined…

The induced electric field in a tokamak drives a parallel electron current flow. In an inhomogeneous, finite beta plasma, when this electron flow is comparable to the ion thermal speed, the Alfven mode wave solutions of the electromagnetic…

Plasma Physics · Physics 2014-03-05 István Pusztai , Peter J. Catto , Felix I. Parra , Michael Barnes

Recently, theoretical analysis has identified plasma microinstabilities as the primary mechanism responsible for anomalous heat transport in tokamaks. In particular, the microtearing mode (MTM) has been credited with the production of…

Plasma Physics · Physics 2021-02-09 A. O. Nelson , F. M. Laggner , A. Diallo , Z. A. Xing , D. R. Smith , E. Kolemen

We investigate the effect of varying the ion temperature gradient (ITG) and toroidal equilibrium scale sheared flow on ion-scale turbulence in the outer core of MAST by means of local gyrokinetic simulations. We show that nonlinear…

Plasma Physics · Physics 2017-10-11 F. van Wyk , E. G. Highcock , A. R. Field , C. M. Roach , A. A. Schekochihin , F. I. Parra , W. Dorland

Weakly collisional plasmas dynamically develop pressure anisotropies with respect to the magnetic field. These anisotropies trigger plasma instabilities at scales just above the ion Larmor radius \rho_i and much below the mean free path…

High Energy Astrophysical Phenomena · Physics 2015-05-18 M. S. Rosin , A. A. Schekochihin , F. Rincon , S. C. Cowley

The characteristics of ion temperature gradient (ITG) turbulence in the presence of a magnetic island are numerically investigated using a gyrokinetic model. We observe that in the absence of the usual ITG drive gradient, a solitary…

Plasma Physics · Physics 2023-12-29 Jingchun Li , J. Bao , Z. Lin , J. Q. Dong , Yong Liu , Y. R. Qu

This study comprehensively investigates fast ion-driven drift instability, extending the theory in [B. J. Kang and T. S. Hahm, Phys. Plasmas 26, 042501 (2019)]. The eigenmode equation, including the resonant contribution of passing fast…

Plasma Physics · Physics 2025-01-24 ByungJun Kang , Hideo Sugama , Tomo-Hiko Watanabe , Masanori Nunami

Gyrokinetic simulations have greatly improved our theoretical understanding of turbulent transport in fusion devices. Most gyrokinetic models in use are delta-f simulations in which the slowly varying radial profiles of density and…

Plasma Physics · Physics 2013-10-01 Felix I. Parra

This study uses two-dimensional molecular dynamics simulations to explore Rayleigh-Taylor-like instability in a strongly coupled binary complex plasma, when heavier dust particles are positioned above the lighter ones, having the same…

Plasma Physics · Physics 2026-01-14 Priya Deshwal , Hitendra K. Malik