Observation of alpha particle loss from JET plasmas during ion cyclotron resonance frequency heating using a thin foil Faraday cup detector array

Darrow, D. S.; Cecil, F. E.; Kiptily, V.; Fullard, K.; Horton, A.; Murari, A.; JET EFDA Contributors
October 2010
Review of Scientific Instruments;Oct2010, Vol. 81 Issue 10, p10D330
Academic Journal
The loss of MeV alpha particles from JET plasmas has been measured with a set of thin foil Faraday cup detectors during third harmonic heating of helium neutral beam ions. Tail temperatures of ∼2 MeV have been observed, with radial scrape off lengths of a few centimeters. Operational experience from this system indicates that such detectors are potentially feasible for future large tokamaks, but careful attention to screening rf and MHD induced noise is essential.


Related Articles

  • Hamiltonian description of low frequency waves propagation and absorption in magnetically confined plasmas. Dumont, R. J.; Eriksson, L.-G. // AIP Conference Proceedings;2006, Vol. 871 Issue 1, p65 

    Magnetically confined fusion plasmas feature a large variety of waves. In the Ion Cyclotron Range of Frequencies (ICRF), radiofrequency waves are routinely used for plasma heating and non-inductive current-drive, whereas unstable modes in the Alfvén range of frequencies are observed in...

  • Energetic particle mode stability in tokamaks with hollow q-profiles. Zonca, F.; Briguglio, S.; Chen, L.; Dettrick, S.; Fogaccia, G.; Testa, D.; Vlad, G. // Physics of Plasmas;Dec2002, Vol. 9 Issue 12, p4939 

    A thorough analysis of energetic particle modes (EPM) stability and mode structures is presented for tokamaks with hollow q profiles. Focusing on the region near the minimum-q surface, EPM gap modes and resonant EPMs are shown to exist as solutions of the same dispersion relation. By controlling...

  • Edge ion heating and parametric decay during injection of ion cyclotron resonance frequency power on the Alcator C-Mod tokamak. Rost, J. C.; Porkolab, M.; Boivin, R. L. // Physics of Plasmas;Apr2002, Vol. 9 Issue 4, p1262 

    A population of suprathermal ions has been observed in the scrape off layer during injection of power in the ion cyclotron frequency range on the Alcator C-Mod tokamak [I. H. Hutchinson et al., Phys. Plasmas 1, 1511 (1994)]. These ions generated energetic neutrals which were measured with a...

  • Sawtooth stabilization by electron cyclotron heating at the q=1 surface in the WT-3 tokamak. Tanaka, S.; Hanada, K.; Tanaka, H.; Iida, M.; Ide, S.; Minami, T.; Nakamura, M.; Maekawa, T.; Terumichi, Y.; Yamada, M.; Manickam, J.; White, R. B. // Physics of Fluids B: Plasma Physics;Aug91, Vol. 3 Issue 8, p2200 

    Sawtooth oscillations (STO) in the Ohmically heated (OH) WT-3 tokamak [Plasma Physics and Controlled Nuclear Fusion Research 1988 (IAEA, Vienna, 1989), Vol. 1, p. 563] are strongly modified or suppressed by localized electron cyclotron resonance heating (ECH) near the q = 1 surface, where q...

  • Suppression of a pressure driven m=1 mode in a lower hybrid current drive plasma by electron cyclotron heating in the WT-3 tokamak. Yoshimura, S.; Watanabe, M.; Tanabe, K.; Nakayama, A.; Asakawa, M.; Maehara, T.; Nakamura, M.; Tanaka, H.; Maekawa, T.; Terumichi, Y. // Physics of Plasmas;Jan2000, Vol. 7 Issue 1 

    A pressure driven m=1/n=1 mode is excited by lower hybrid current drive in the WT-3 tokamak [T. Maehara et al., Nucl. Fusion 38, 39 (1998)]. The excitation of the mode is accompanied with the decrease of the magnetic shear and with the peaking of the soft x-ray emissivity profile inside the q=1...

  • A drift-magnetohydrodynamical fluid model of helical magnetic island equilibria in the pedestals of H-mode tokamak plasmas. Fitzpatrick, R.; Waelbroeck, F. L. // Physics of Plasmas;Jun2010, Vol. 17 Issue 6, p062503 

    A drift-magnetohydrodynamical (MHD) fluid model is developed for an isolated, steady-state, helical magnetic island chain, embedded in the pedestal of a large aspect ratio, low-β, circular cross section, H-mode tokamak plasma, to which an externally generated, multiharmonic, static magnetic...

  • Saturation of a single mode driven by an energetic injected beam. III. Alfvén wave problem. Berk, H. L.; Breizman, B. N. // Physics of Fluids B: Plasma Physics;Sep90, Vol. 2 Issue 9, p2246 

    The saturation amplitude of Alfvén waves, excited by alpha particles produced in an ignited tokamak, is estimated. The formalism that has been developed to describe the saturation of a single mode is generalized to toroidal geometry. The saturation level is estimated for the toroidal...

  • Tomography of full sawtooth crashes on the Tokamak Fusion Test Reactor. Nagayama, Y.; Yamada, M.; Park, W.; Fredrickson, E. D.; Janos, A. C.; McGuire, K. M.; Taylor, G. // Physics of Plasmas;May96, Vol. 3 Issue 5, p1647 

    Studies full sawtooth crashes in high temperature plasmas on the Tokamak Fusion Test Reactor (TFTR). Asymmetry in the direction of major radius after observation of the crash with electron cyclotron emission image reconstructions; Comparison of TFTR data with two-dimensional models; Explanation...

  • Self-Consistent Modelling of Polychromatic ICRH in Tokamaks. Laxåback, M.; Johnson, T.; Hellsten, T.; Mantsinen, M. // AIP Conference Proceedings;2003, Vol. 694 Issue 1, p126 

    Polychromatic, multi-frequency, ion cyclotron resonance heating provide a useful tool for the optimization of plasma performance in fusion devices by tailoring the fast ion distribution function. Not only can the radial profile of the fast ion distributions be modified, but also the fast energy...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics