SLAC, Menlo Park, California, USA
A RF gun photocathode test facility has been commissioned at SLAC. The facility consists of a S-band gun, high power RF, a UV drive laser and beam diagnostics. Here we report on the capabilities of the facility demonstrated during commissioning. Currently the facility is being used to study in-situ laser processing of copper photocathodes. In the future the facility will be used to study fundamental gun and photocathode performance limitations and enhancement strategies. Eventually it is envisioned to integrate a load lock and plug into the gun enabling the evaluation of high performance surface sensitive semiconductor photocathodes and the incorporation of ex-situ surface science analytical techniques.
THOANO02
SLAC, Menlo Park, California, USA
Following the successful demonstration of echo-enabled harmonic generation [1] (EEHG [2]) with n=7 [3] at SLAC's NLCTA in 2011 [4], the beam line has been upgraded recently to benchmark EEHG theory at much higher harmonics. An optical parametric amplifier has been used to provide a seed with wavelength at 2.4 μm. Using an rf undulator as the radiator, coherent radiation at the 14th harmonic of the seed, i.e. with wavelength at 171 nm, has been generated using EEHG technique with a 120 MeV beam. We will present detailed experimental results on testing EEHG at n=14. Future plans in testing EEHG at n=30~75 in the coming year will be briefly discussed as well.
[1] G. Stupakov, PRL 102, 074801 (2009).
[2] D. Xiang and G. Stupakov, PRST-AB 12, 030702 (2009).
[3] D. Xiang et al., PRL 105, 114801 (2010).
[4] D. Xiang et al., PRL 108, 024802 (2012)
