Temporal synchronization of GHz repetition rate electron and laser   pulses for the optimization of a compact inverse-Compton scattering x-ray   source
  The operation of an inverse-Compton scattering source of x-rays or gamma-rays requires the precision alignment and synchronization of highly focused electron bunches and laser pulses at the collision point. The arrival times of electron and laser pulses must be synchronized with picosecond precision. We have developed an RF synchronization technique that reduces the initial timing uncertainty from 350 ps to less than 2 ps, greatly reducing the parameter space to be optimized while commissioning the x-ray source. We describe the technique and present measurements of its performance. 
Michael R. Hadmack and Eric B. Szarmes and John M.J. Madey and Jeremy   M.D. Kowalczyk
physics.acc-ph