Measurement of ion motion in a shear Alfvén wave
نویسندگان
چکیده
In this study, the technique of laser-induced fluorescence sLIFd has been used to meausure Ti and the E3B0 and polarization drifts of shear Alfvén waves in the Large Plasma Device at UCLA fW. Gekelman, H. Pfister, Z. Lucky, J. Bamber, D. Leneman, and J. Maggs, Rev. Sci. Instrum. 62, 2875 s1991dg. The waves were launched by an antenna located at the end of the device and were observed to propagate along the axis of a 9 m long, 40 cm diameter cylindrical argon plasma in the kinetic regime fbe<9.5sme /midg, with fwave / fci<0.8. Care was taken to record the measurements from various diagnostics at the same spatial positions on four cross-sectional planes along the length of the plasma. Two-dimensional LIF measurements of the ion drifts perpendicular to B0 were undertaken. Ion drifts were observed to be as large as 14% of the ion thermal speed. The ion polarization and E3B0 drifts were distinguished by their phase relation to Bwave. The measured drifts are compared to kinetic theory. E' sthe transverse component of Ewaved was computed from the drift velocities, and Ei was estimated from E'. © 2005 American Institute of Physics. fDOI: 10.1063/1.1930796g
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