The monopole monotron instability is a well-known phenomenon in linear beam devices. In recent development of high-efficiency 50-MW X-band klystron, such instabilities were found and mitigated special second-harmonic multicell cavities triplet that used to improve the klystron's performance. further simulations using 3-D particle-in-cell computer codes, more rare complicated phenomenon, previou...

Lattice changes in the PEP-II high energy ring have made the concept of driving four cavities with a single klystron an attractive option. This paper examines the topology from a RF feedback point of view. Sources of error are identified and their magnitudes are estimated. The effect on the performance of the longitudinal impedance reducing feedback loops is calculated using control theory and ...

This paper introduces an iterative approach to producing flat-topped radio frequency (RF) pulses for driving the pulsed linear accelerators in the Swiss free electron laser (SwissFEL). The method is based on model-free iterative learning control which iteratively updates the input pulse shape in order to generate the desired amplitude and phase pulses at the output of the RF system. The method ...

A technique for plroducing ultra-short electron bunches (e.g., 5100 fs) from a continuous electron beam using a short plasma wave section and a drift space is explored. The bunches are a fraction of a plasma wavelength long and are spaced by a plasma wavelength, making them of interest for iinjection into plasma accelerators or for driving a klystron-like structure to produce infrared radiation.