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Related papers: Microstability of $\beta \sim 1$ tokamak equilibri…

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Upper bounds on the growth of instabilities in gyrokinetic systems have recently been derived by considering the optimal perturbations that maximise the growth of a chosen energy norm. This technique has previously been applied to…

Plasma Physics · Physics 2024-04-10 P. J. Costello , G. G. Plunk

Negative triangularity (NT) tokamak configurations have several key benefits including sufficient core confinement, improved power handling, and reduced edge pressure gradients that allow for edge-localized mode (ELM) free operation. We…

Advanced tokamak regimes, featuring extended regions of low magnetic shear, are promising candidates for future fusion reactors but are also more prone to specific kinds of MHD instabilities. The proximity to a rational surface in a very…

Plasma Physics · Physics 2025-09-04 M. Coste-Sarguet , J. P. Graves

A two dimensional flow model is introduced with deterministic behavior consisting of bursts which become successively larger, with longer interburst time intervals between them. The system is symmetric in one variable x and there are bursts…

Chaotic Dynamics · Physics 2009-11-11 J. M. Finn , E. R. Tracy , W. E. Cooke , A. S. Richardson

Proton-Boron fusion requires extreme ion temperatures and robust confinement, making Spherical Tokamaks (ST) with high-power neutral beam injection primary candidates. In these devices, strong toroidal rotation and the large mass disparity…

Traditional centralized stability analysis struggles with scalability in large complex modern power grids. This two-part paper proposes a compositional and equilibrium-free approach to analyzing power system stability. In Part I, we prove…

Systems and Control · Electrical Eng. & Systems 2025-06-16 Peng Yang , Xiaoyu Peng , Xi Ru , Hua Geng , Feng Liu

Electromagnetic (EM) instabilities and turbulence driven by the electron-temperature gradient are considered in a local slab model of a tokamak-like plasma. The model describes perturbations at scales both larger and smaller than the…

Plasma Physics · Physics 2022-08-30 T. Adkins , A. A. Schekochihin , P. G. Ivanov , C. M. Roach

Forty-five years ago a coordinate system was shown to exist that gave simple but exact expressions whenever and wherever a toroidal plasma equilibrium $\vec{\nabla}p=\vec{j}\times\vec{B}$ exists. These coordinates, now called Boozer…

Plasma Physics · Physics 2026-04-21 Allen H Boozer

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

Disruptions are a serious issue in tokamaks. In a disruption, the thermal energy is lost by means of an instability which could be a resistive wall tearing mode (RWTM). During precursors to a disruption, the plasma edge region cools,…

Plasma Physics · Physics 2023-08-16 H. R. Strauss

An analytic equilibrium, the Toroidal Bessel Function Model, is used in conjunction with the gyrokinetic code GYRO to investigate the nature of microinstabilities in a reversed field pinch (RFP) plasma. The effect of the normalized electron…

Plasma Physics · Physics 2015-06-12 Daniel Carmody , M. J. Pueschel , P. W. Terry

Development and operation of commercially viable fusion energy reactors such as tokamaks require accurate predictions of plasma dynamics from sparse, noisy, and incomplete sensors readings. The complexity of the underlying physics and the…

A local magnetic equilibrium solution is sought around the magnetic axis in order to identify the key parameters defining the magnetic-surface's up-down asymmetry in the core of tokamak plasmas. The asymmetry is found to be determined…

Plasma Physics · Physics 2014-10-08 Paulo Rodrigues , Nuno F. Loureiro , Justin Ball , Felix I. Parra

Magnetic islands play a crucial role in regulating plasma confinement in tokamaks by interacting with micro-instabilities, such as the ion temperature gradient (ITG) mode. This work presents a detailed investigation of the effects of static…

In this study, global nonlinear electromagnetic gyrokinetic simulations are conducted to investigate turbulence in the Internal transport barrier (ITB) region of the EAST tokamak discharge with weakly reversed magnetic shear. Linear…

Plasma Physics · Physics 2025-11-07 Yuehao Ma , Pengfei Liu , Jian Bao , Zhihong Lin , Huishan Cai

High-temperature superconducting (HTS) magnets and other advances have led to renewed interest in magnetic mirrors for fusion energy. The non-Maxwellian nature of mirror plasmas necessitates kinetic modeling to predict, optimize and design…

Plasma Physics · Physics 2026-05-29 Maxwell H. Rosen , Manaure Francisquez , Ammar Hakim , Gregory W. Hammett

In the merging-compression method of plasma start-up, two flux-ropes with parallel toroidal current are formed around in-vessel poloidal field coils, before merging to form a spherical tokamak plasma. This start-up method, used in the…

Plasma Physics · Physics 2014-03-04 A. Stanier , P. Browning , M. Gordovskyy , K. G. McClements , M. P. Gryaznevich , V. S. Lukin

Out of thermal equilibrium, an environment imposes effective mechanical forces on microscopical nanofabricated devices, chemical or biological systems. Here we address the question of how to calculate these forces together with the response…

Statistical Mechanics · Physics 2017-05-24 A. Feigel

In this bachelor's thesis, isotope effects for pedestal instabilities have been studied based on an ASDEX Upgrade H-Mode scenario. This was done using the JOREK code for extended MHD simulations, including the ion diamagnetic drift and the…

Plasma Physics · Physics 2024-08-09 Matthias Rosenthal

A highly elongated plasma is desirable in order to increase plasma pressure and energy confinement to maximize fusion power output. However, there is a limit to the maximum achievable elongation which is set by vertical instabilities driven…

Plasma Physics · Physics 2017-05-24 Jungpyo Lee , Jeffrey P. Freidberg , Antoine J. Cerfon , Martin Greenwald