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تسجيل مستخدم جديدDynamic stabilization of plasma instability
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The paper presents a review of dynamic stabilization mechanisms for plasma instabilities. One of the dynamic stabilization mechanisms for plasma instability was proposed in the papers [Phys. Plasmas 19, 024503(2012) and references therein], based on a perturbation phase control. In general, instabilities emerge from the perturbations of the physical quantity. Normally the perturbation phase is unknown so that the instability growth rate is discussed. However, if the perturbation phase is known, the instability growth can be controlled by a superimposition of perturbations imposed actively: if the perturbation is introduced by, for example, a driving beam axis oscillation or so, the perturbation phase can be controlled and the instability growth is mitigated by the superimposition of the growing perturbations. Based on this mechanism we present the application results of the dynamic stabilization mechanism to the Rayleigh-Taylor (R-T) instability and to the filamentation instability as typical examples in this paper. On the other hand, in the paper [Comments Plasma Phys. Controlled Fusion 3, 1(1977)] another mechanism was proposed to stabilize the R-T instability based on the strong oscillation of acceleration, which was realized by the laser intensity modulation in laser inertial fusion [Phys. Rev. Lett. 71, 3131(1993)]. In the latter mechanism, the total acceleration strongly oscillates, so that the additional oscillating force is added to create a new stable window in the system. Originally the latter mechanism was proposed by P. L. Kapitza, and it was applied to the stabilization of an inverted pendulum. In this paper we review the two dynamic stabilization mechanisms, and present the application results of the former dynamic stabilization mechanism.
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