P. Mantica D. Van Eester X. Garbet F. Imbeaux L. Laborde M. Mantsinen A. Marinoni D. Mazon D. Moreau N. Hawkes E. Joffrin V. Kiptily S. Pinches A. Salmi S. Sharapov A. Thyagaraja I. Voitsekhovitch P. De Vries K.-D. Zastrow
The first electron temperature modulation experiments in plasmas characterized by strong and longlasting electron and ion internal transport barriers (ITB) have been performed in JET using ion cyclotron resonance heating in mode conversion scheme. The ITB is shown to be a well localized narrow layer with low heat diffusivity, characterized by subcr…
PublishedP. Sandquist S. E. Sharapov P. Helander M. Lisak
A corrected relativistic collision operator is used to derive a Fokker-Planck equation for the distribution function of relativistic suprathermal electrons in a weakly relativistic plasma, which is then solved by a procedure similar to that employed in Connor and Hastie [Nucl. Fusion 15 , 415 (1975)]. Analytical expressions are derived for the elec…
PublishedI. T. Chapman S. E. Sharapov G. T. A. Huysmans A. B. Mikhailovskii
A new code, MISHKA-F Flow, has been developed as an extension of the ideal magnetohydrodynamic MHD code MISHKA-1 [Mikhailovskii and et al. , Plasma Phys. Rep. 23 , 844 (1997)] in order to investigate the linear MHD stability of ideal and resistive eigenmodes with respect to the effects of toroidal rotation in tokamaks in general toroidal geometry w…
PublishedG. J. Kramer R. Nazikian B. Alper M. De Baar H. L. Berk G.-Y. Fu N. N. Gorelenkov G. Mckee S. D. Pinches T. L. Rhodes S. E. Sharapov W. M. Solomon M. A. Van Zeeland JET EFDA Contributors
Reversed shear Alfvén eigenmodes RSAE that were observed in the Joint European Torus (JET) [P. H. Rebut and B. E. Keen, Fusion Technol. 11 , 13 (1987)] and DIII-D [J. L. Luxon, Nucl. Fusion 42 , 614 (2002)] are studied with the ideal magnetohydrodynamic code NOVA-K C. [Z. Cheng, Phys. Rep. 211 , 1 (1992)]. It was found that the frequency behavior …
PublishedI.T. Chapman S. Saarelma T.C. Hender S.E. Sharapov G.T.A. Huysmans A.B. Mikhailovskii H. Meyer A. Kirk H.R. Wilson
Present day tokamaks are capable of generating toroidal flows approaching the ion sound speed. Such toroidal rotation is known to have a stabilising effect on resistive wall modes[1]. Here the effects of plasma rotation and diamagnetic drifts on the n = 1 internal kink mode and high n ballooning modes are presented with specific comparison to exper…
PublishedJ. A. Snipes N. Basse C. Boswell E. Edlund A. Fasoli N. N. Gorelenkov R. S. Granetz L. Lin Y. Lin R. Parker M. Porkolab J. Sears S. Sharapov V. Tang S. Wukitch
Alfven eigenmodes (AEs) are studied to assess their stability in high density reactor relevant regimes. Stable AEs are excited with active magnetohydrodynamics antennas in the range of the expected AE frequency. Toroidal Alfven eigenmode (TAE) damping rates have been observed in diverted and limited Ohmic plasmas. Energetic particle modes or TAEs h…
PublishedThawatchai Onjun Arnold H. Kritz Glenn Bateman Vassili Parail
Self-consistent simulations of the International Thermonuclear Experimental Reactor (ITER) [R.Aymar, P. Barabaschi, and Y. Shimomura, Plasma Phys. Controlled Fusion 44, 519 (2002)] have been carried out using the JETTO-integrated modeling code in which theory-motivated models are used for the H-mode pedestal and for the stability conditions that le…
PublishedS. E. Sharapov B. Alper J. Fessey N. C. Hawkes N. P. Young R. Nazikian G. J. Kramer D. N. Borba S. Hacquin E. De La Luna S. D. Pinches J. Rapp D. Testa JET-EFDA Contributors
A microwave interferometry technique is applied for the first time for detecting a discrete spectrum of Alfvén cascade (AC) eigenmodes excited with fast ions in reversed magnetic shear plasmas of the Joint European Torus. The interferometry measurements of plasma density perturbations associated with ACs show an unprecedented frequency and time re…
PublishedG. J. Kramer S. E. Sharapov R. Nazikian N. N. Gorelenkov R.V. Budny
Experimental evidence is presented for the existence of the theoretically predicted odd toroidicity induced Alfve?n eigenmode (TAE) from the simultaneous appearance of odd and even TAEs in a normal shear discharge of the joint European torus. The modes are observed in low central magnetic shear plasmas created by injecting lower hybrid current driv…
PublishedS.E. Sharapov A.B. Mikhailovskii G.T.A. Huysmans
The effects of nonresonating hot ions on the spectrum of magnetohydrodynamic (MHD) waves and instabilities in tokamaks are studied in the limit when the width of the hot ion drift orbits is much larger than the radial scale length of the MHD perturbations. Due to the large magnetic drift velocities the hot ions cannot contribute to the MHD perturb…
Published