Laser system for the TTF photoinjector at Fermilab
Proceedings of the 1997 Particle Accelerator Conference (Cat. No.97CH36167)
We have developed a solid-state laser system to meet the requirements of the TESLA Test Facility (TTF) photoinjector, currently under development at Fermilab. The laser produces a 1 MHz train of up to 800 equal-amplitude pulses with up to 1 mJ per pulse (0.8 J per macropulse) at λ = 1054 nm. The laser pulse train is produced by a phase-stabilized, mode-locked, Nd:YLF oscillator and a fast selection Pockels cell. The pulses are amplified in an Nd:glass amplifier chain consisting of a multipass
... ng of a multipass rod amplifier and a 5-pass zig-zag slab amplifier. The laser system employs chirped pulse amplification (CPA) to produce 10 ps pulses. After fourth harmonic generation of the laser to λ = 263 nm, 10 nC electron bunches can be extracted from a Cs 2 Te photocathode in the RF gun. TTF PHOTONINJECTOR DEVELOPMENT A collaboration has been formed between FNAL, DESY, UCLA, INFN Milano, and the University of Rochester to develop a state-of-the-art photoinjector with a novel bunch structure for the Tesla Test Facility (TTF). The injector will consist of an RF gun (UCLA, FNAL) with a highquantum efficiency photocathode (INFN Milano) driven by an advanced laser system (Rochester), and a superconducting linear accelerator cavity (DESY). The FNAL/TTF RF photoinjector is designed to match the requirements of the TTF accelerator, namely high bunch charge (8 nC), low emittance (< 20 mm-mr) and high duty cycle (1%). The TTF pulse train consists of 800 bunches of 8 nC, spaced 1 µs apart, with a 10 Hz rep rate. The beam optics are optimized for an overall injector consisting of the electron gun followed by one linac capture section and a dipole chicane for magnetic bunch compression  .