Alpha Channeling in a Rotating Plasma

The wave-particle alpha-channeling effect is generalized to include rotating plasma. Specifically, radio frequency waves can resonate with alpha particles in a mirror machine with ExB rotation to diffuse the alpha particles along constrained paths in phase space. Of major interest is that the alpha-particle energy, in addition to amplifying the RF waves, can directly enhance the rotation energy which in turn provides additional plasma confinement in centrifugal fusion reactors. An ancillary benefit is the rapid removal of alpha particles, which increases the fusion reactivity.Comment: 4 pages and 3 figure

Characterization of ion species mix of the TEXTOR diagnostic hydrogen beam injector with a rf and arc-discharge plasma box

The ion specie fractions of the diagnostic hydrogen beam of TEXTOR tokamak have been determined by making use of a H-alpha-light Doppler shift spectroscopy and alternatively by a magnetic mass spectrometer. The measurements were done for the fixed beam energy of 50 keV and beam current variable up to 2.5 A. According to the measurements, the full energy beam component is for a radio frequency plasma box similar to50% by the particle density and more than 75% for an arc-discharge plasma box. (C) 2004 American Institute of Physics

Upgrade of the diagnostic neutral beam injector for the TCV tokamak

A diagnostic neutral beam injector (DNBI) [CRPP report LRP 710/01, CRPP-EPFL, 200 1; EPS Conf. Comr. Fusion Plasma Phys., 25A (2001) 365] has been installed on tokamak A configuration variable (TCV) [Plasma Phys. Control Fusion, 36 (1994) 13277; Plasma Phys. Control Fusion, 43 (200 1) A 16 1; Plasma Phys. Control Fusion, to be published] for the purpose of providing local measurements of plasma ion temperature, velocity and impurity density by Charge exchange recombination spectroscopy (CXRS) [EPS Conf. Contr. Fusion Plasma Phys., 25A (2001) 365]. The system recently underwent a technical upgrade, which allowed to increase the full neutral beam current density by a factor of two (from 0.5 to 1 A at 52 keV injection energy) and to extend the operational range of the diagnostic. This was achieved by means of a new, larger ion source, with an increased extraction area and corresponding enhancements of the power supplies. (C) 2003 Elsevier B.V. All rights reserved