Doppler-shifted cyclotron resonance of fast ions with circularly polarized shear Alfvén waves
نویسندگان
چکیده
The Doppler-shifted cyclotron resonance between fast ions and shear Alfvén waves SAWs has been experimentally investigated with a test-particle fast-ion Li+ beam launched in the helium plasma of the Large Plasma Device Gekelman et al., Rev. Sci. Instrum. 62, 2875 1991 . Leftor right-hand circularly polarized SAWs are launched by an antenna with four current channels. A collimated fast-ion energy analyzer characterizes the resonance by measuring the nonclassical spreading of the averaged beam signal. Left-hand circularly polarized SAWs resonate with the fast ions but right-hand circularly polarized SAWs do not. The measured fast-ion profiles are compared with simulations by a Monte Carlo Lorentz code that uses the measured wave field data. © 2009 American Institute of Physics. DOI: 10.1063/1.3103813
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