Fast-particle-driven Alfvénic modes in a reversed field pinch.
نویسندگان
چکیده
Alfvénic modes are observed due to neutral beam injection for the first time in a reversed field pinch plasma. Modeling of the beam deposition and slowing down shows that the velocity and radial localization are high. This allows instability drive from inverse Landau damping of a bump-on-tail in the parallel distribution function or from free energy in the fast ion density gradient. Mode switching from a lower frequency toroidal mode number n=5 mode that scales with beam injection velocity to a higher frequency n=4 mode with Alfvénic scaling is observed.
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ورودعنوان ژورنال:
- Physical review letters
دوره 109 11 شماره
صفحات -
تاریخ انتشار 2012