Field line resonances in a cylindrical plasma
نویسندگان
چکیده
An experimental study of the response to an impulsive driver in a low beta helium plasma is presented. Field line resonance ~FLR! spectra are recorded and compared to an ideal magnetohydrodynamic ~MHD! theory with finite ion cyclotron frequency corrections. The agreement between observed and predicted values is generally within the frequency resolution of the measurements except for the lowest frequency harmonic. The spectrum of the lowest harmonic is compared to various ultra low-frequency ~ULF! FLR dispersion relations. Dispersion effects due to nonzero perpendicular wave number are found to be important for the lowest frequency harmonic. Quality factors are measured and compared to theoretical estimates from a two-fluid theory with finite parallel electron temperature. Reflection coefficient values are obtained using measured and estimated Q values. © 2002 American Institute of Physics. @DOI: 10.1063/1.1483310#
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