Observations of the PSR transverse instability

A fast instability with beam loss is observed in the Los Alamos Proton Storage Ring (PSR) when the injected beam current exceeds thresholds, with both bunched and unbunched beams. Large coherent transverse oscillations occur before and during beam loss. Recent observations of the instability indicate that it is an e-p-type instability, driven by coupled oscillations due to electrons trapped within the proton beam.<
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