Transient Beam Loading in the Als Harmonic Rf System*
نویسندگان
چکیده
We report on the commissioning of a higher harmonic radiofrequency system at the Advanced Light Source, designed to improve the beam lifetime. We have achieved an increase above a factor of two in our best results up to now. Transient beam loading of the harmonic cavities, due to the unequal fill patterns, creates the greatest limitations on lifetime improvement. We also describe several interesting effects on the operation of the longitudinal and transverse multibunch feedback systems.
منابع مشابه
Computed Transient Beam Loading Effects with Harmonic RF Systems
Harmonic cavities have been used in storage rings to lengthen bunches and increase beam lifetimes dominated by Touschek scattering. Transient beam loading in the harmonic cavities generated by asymmetries in the fill pattern can cause significant variation of the beam phase and bunch length along the bunch train when the longitudinal restoring force has been reduced, resulting in a significant ...
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