Effect of Feedback and Noise on Fast Ion Instability*
نویسندگان
چکیده
“ -‘ One can use a feedback system to suppress the fmt ion instability. However, the feedback noise (and also other sources of noise in the machine) c-ontinously excites the transient oscillations in the electron beam that are m“plified through the electron interaction with the ions. We calculate the equilibrium level of these oscillations under the influence of the feedback and show how they grow exponentially from the head to the tail of the bunch train in a linear theory. Nonlinear saturation effects are assume negligible. Presented atInt~rnational Worbhop on Multi-Bunch Instabilities in Future Electron and Positron Accelemtors Tsukuba, Japan July 15-18, lgg7 — —. *Work supported by Department of Energy contract DEAC03-76SFO0515. Effect of Feedback and Noise on Fast Ion Instability Abstract One can use a feedback system to suppress the fast ion instability. However, the feedback continuously excites noise (and also other sources of noise in the machine) the transient oscillations in the electron beam that are amplified through the electron interaction with the ions. We calculate the equilibrium level of these oscillations under the influence of the feedback and . .-show how they grow exponentially from the train in a linear theory. Nonlinear saturation head to the tail of the bunch effects are assume negligible. — —.
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