Laboratory realization of an ion‐ion hybrid Alfvén wave resonator
نویسندگان
چکیده
[1] In a magnetized plasma with two ion species, shear Alfvén waves (or guided electromagnetic ion cyclotron waves) have zero parallel group velocity and experience a cut‐off near the ion‐ion hybrid frequency. Since the ion‐ion hybrid frequency is proportional to the magnetic field, it is possible, in principle, for a magnetic well configuration to behave as an Alfvén wave resonator in a two‐ion plasma. This study demonstrates such a resonator in a controlled laboratory experiment using a H‐He mixture. The resonator response is investigated by launching monochromatic waves and sharp tone‐bursts from a magnetic loop antenna. The observed frequency spectra are found to agree with predictions of a theoretical model of trapped eigenmodes. Citation: Vincena, S. T., W. A. Farmer, J. E. Maggs, and G. J. Morales (2011), Laboratory realization of an ion‐ion hybrid Alfvén wave resonator, Geophys. Res. Lett., 38, L11101, doi:10.1029/2011GL047399.
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Investigation of an ion-ion hybrid Alfv en wave resonator
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