Using beam echo to recover transverse emittance
نویسندگان
چکیده
If the beam is injected into the ring with an offset a, it undergoes betatron oscillation. After the oscillation decoheres, the beam transverse emittance increases by ∆ε . To avoid this emittance increase one typically uses a feedback (or damper) that takes out the oscillation before it damps down. We show that using echo one can recover a fraction of ∆ε long after the beam oscillation decoheres.
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