Sasha Gilevich, Alan Miahnahri Drive Laser 11/4/2004 Agenda General Information Project Status Transport Tubes Design Gun Region Design Other Issues Meetings Materials are in the V:\AD\Drop boxes\Bolton\LCLS Drive Laser Meetings

Sasha Gilevich, Alan Miahnahri Drive Laser 11/4/2004 Transport Tube UV Launch and Condition. Laser Heater Drive Laser RF Gun Laser Bay Photocathode Gun & Launch System Laser Heater Transport Tubes Electron Diagnostic Sector 20 Alcove Sector 20 Drive Laser System

Sasha Gilevich, Alan Miahnahri Drive Laser 11/4/2004 UV Pulse Specifications ParameterSystem RequirementComments Pulse repetition rate120 HzOperating rates of 1, 10, 30, 60 and 120 Hz Pulse Energy>0.2 mJ at 255nm (for 1 nC production with 3x10 -5 QE) Continuously adjustable Central Wavelength nm Pulse-to-pulse energy jitterLess than 2%(rms) variation Pulse timing jitter 2 0.1Hz Temporal pulse shape 3 Uniform, flat top, selected slope on flat-top within 3% of goal, and <8% peak-to-peak over flattop, 1 ps rise and fall at 10% to 90% 10% to +20% slope Pulse length10 ps (fwhm)5 to 20 ps 1. Longer wavelength is acceptable, but requires higher energy due to the reduction in cathode QE 2. Measured with respect to the 119 MHz clock – RF signal 3. The temporal pulse shape is nominally flat but the slope of the pulse must be adjustable from -10% (head 10% higher than the tail) to +20% (head 20% lower than the tail). Some adaptive temporal shaping will be required

Sasha Gilevich, Alan Miahnahri Drive Laser 11/4/2004 UV Pulse Specifications ParameterSystem RequirementOperating Range/ Comments Radial shapeUniform, flat top, <10% peak-to-peak variation within flattop plateau for any single pulse) Adjustable slope spot radius1.2 mm< 4 % (shot-to-shot) Centroid Position Stability Less than 3% of the beam radius (1/e 2 level)Measured at the laser output plane Pointing StabilityLess than 25μradMeasured at the laser output plane MTBF>5000 hours

Sasha Gilevich, Alan Miahnahri Drive Laser 11/4/2004 General Information Drive Laser will be a fully purchased and integrated system from the single vendor. Includes UV conversion and temporal shaping Optical transport, launch system, and diagnostics to be built by SLAC

Sasha Gilevich, Alan Miahnahri Drive Laser 11/4/2004 Project Status UV Specifications Defined S20 drive laser facility requirements defined Title II facility design started Drive Laser (DL) Technical Review Committee created 1st meeting July 21, 2004 Procurement process for the Drive Laser started: SOW written APP approved Purchasing putting together the RFP package Design of the transport tubes started Mechanical and Optical design of the Launch and Conditioning System Started R&D effort is defined and started LCLS performs shaping & UV conversion R&D with other labs (BNL, LLNL…)

Sasha Gilevich, Alan Miahnahri Drive Laser 11/4/2004 Transport Tubes Design

Sasha Gilevich, Alan Miahnahri Drive Laser 11/4/2004 Gun Region Design

Sasha Gilevich, Alan Miahnahri Drive Laser 11/4/2004 Gun Region Design Spatial Beam Shaping Newport Refractive Beam Shaper Two aspheric lenses Input Beam Output Beam

Sasha Gilevich, Alan Miahnahri Drive Laser 11/4/2004 Gun Region Design Shaper Grating Aperture Windows Positive Lenses Cathode Window

Sasha Gilevich, Alan Miahnahri Drive Laser 11/4/2004 Gun Region Design Bandwidth 4nm