Commissioning plan for UED@ASTA Renkai Li 5/20/2014 ALD UED@ASTA Review

Pre-operation preparation Commissioning plan Outline Pre-operation preparation Commissioning plan Machine operation and e-beam characterization Transverse overlap of laser and e-beam Temporal overlap of laser and e-beam Summary

Pre-operation preparation Checklist Safety Training Trigger and timing Equipment protection Modulator, klystron, LL and high power rf Alignment rf gun Laser Magnets and power suppliers Motors/actuators Cameras Diagnostics Data management Software UED@ASTA preparation checklist

Pump-probe control and data acquisition 1 D1 S1 e-beam BS D2 sample C2 S2 delay stage EMCCD Computer > 100 M/s gun control delay stage Shutter S1/S2 acquire photodiode D1/D2 Virtual pump Camera C2 EMCCD Computer transfer To be built and tested off-line. Sample holder trigger

Commissioning plan Laser optics installed by July 15th Beamline installation July 15th – July 31th Aim to run e-beams starting from August 1st w/o sample chamber

Machine operation and e-beam characterization Most tasks ready by August 1st Safety Training Trigger and timing Equipment protection Modulator, klystron, LL and high power rf Alignment rf gun Laser Magnets and power suppliers Motors/actuators Cameras Diagnostics Data management Software August 1st – 15th Operation of the machine e-beam energy, charge, spot size Stability of e-beam parameters shot-to-shot fluctuation long-term (a few hours) stability August 15th - Sample holder control laser and e-beam transverse overlap laser and e-beam temporal overlap

Transverse laser and e-beam overlap aperture (4-5 mm diameter) He-Ne steering coils laser e-beam screen camera stage Sample holder at UCLA screen SiN window (broken) SiN window

Temporal laser and e-beam overlap Steps to find time-zero 1) Fast photodiode D1 and D2 (< 100 ps or 3 cm) 2) Measure the rest of optical path length (~1 cm) 3) time-of-flight of the e-beam (from simulation) 4) Ultrafast plasma lensing effect (<1 ps) 2000 mesh TEM Grid -8 ps -4 ps 0 ps 4 ps 8 ps 12 ps 16 ps 20 ps 28 ps 3 MeV beam up to ~50 J/cm2 L0 L C. M. Scoby et al., dx.doi.org/10.1016/j.ultramic.2012.07.015 400 fs step size J. R. Dwyer et al., Phil. Trans. R. Soc. A 364, 741 (2006) H. Park et al., RSI 76, 083905 (2005)

Summary Pre-operation preparation (checklist, now – August 1st) Machine operation / e-beam characterization (August 1st - ) Transverse overlap of laser and e-beam Temporal overlap of laser and e-beam Experiment using samples with ultrafast (100 fs) response Thank you!