LCLS Injector Update D. H. Dowell, SLAC FAC Review, October 12-13, 2004

1. LCLS Injector UpdateD. H. Dowell, SLACFAC Review, October 12-13, 2004 Injector Performance Requirements Conventional Facilities Update Shield Wall Installed Sector 20 Alcove Title I complete Title II begun RF Design Update Drive Laser Update Injector Physics Update Summary

2. LCLS Injector Performance Requirements:

3. RF Gun & Solenoid L0-1 & L0-2 3-m SLAC Sections Load Lock Laser Heater & Chicane Gun Diagnostics Transverse RF Cavity Electro-Optic Diagnostic OTR Emittance Diagnostics Radiation Shield Walls 35o Bend Straight Ahead Spectrometer SLAC Main Linac Beamline LCLS Injector Configuration

4. S20 Floor Plan • Cable Plant Specs Defined • Title II Design Started See PRD: Conventional Facilities Specifications For the Sector 20 Alcove

5. RF Design Progress • L0-1 Accelerator section • Dual feed RF design complete • L0-1 engineering design nearly complete • 120 Hz Gun • Solenoid design complete • RF design nearly complete • Redesigned coupler holes solved pulsed heating problem • Adopted racetrack geometry for full cell • Held technical meetings with prospective vendors • Unresolved issues: • Final design for bulk cooling system • Load lock deferred • Decide how much SLAC vs. vendor engineering and fabrication • Technical review first week of November

6. Dual Feed RF Gun and Solenoid • Dual Feed/Racetrack Design Corrects RF Fields to Second Order • Solenoid Design Includes Both Dipole and Quadrupole Field Correctors

7. Localized Pulsed Heating of RF Coupling Port Gun body stress in Pa • Localized heating of the RF coupling port. • The heat flux (watts/m2) is shown for the gun operating at 140 MV/m and 120 Hz. • Total dissipated power is 3676 watts. • The BNL/SLAC/UCLA gun design • has a DT of 137oC/pulse at the port. • The redesigned port gives a DT of • 41oC/pulse. • NLC designs limit DT to 50oC/pulse ANSYS Analysis: John Hodgson and Nancy Yu Pulse Heating Analysis: Zenghai Li and Liling Xiao

8. L0-1 Structure RF Design

9. L0-1 Structure RF Dual Feed

10. Drive Laser Update (Details in “Drive Laser Update” Presentation) • Technical Review Committee Assembled • C. Barty (LLNL) chairman, M. Babzien (BNL), R. Falcone (Berkeley), Y. Li (ANL) • Review Held July 21, 2004 at SLAC • Committee involved in procurement process • Laser baseline design is diode-pumped Ti:Sapphire based upon extensive discussions with vendors • Request for Proposal ready to submit to vendors • Laser pulse shaping studies underway at BNL/DUVFEL • Developing collaboration with LLNL on both near term and long term laser needs

11. 8% modulation Injector Physics, see breakout Diagnostics and Commissioning Gun measurements Accurate thermal evaluation Gun spectrometer 6D beam characterization at 135 MeV Simulations Low Charge tunings RF studies L01 dual feed, racetrack shape necessary RF gun dual feed, racetrack shape in full cell mode 0 studies 8MHz mode separation better klystron pulse shaped

12. Injector Schedule • Schedule Coordinated with Shutdowns • Over a Year for Injector Commissioning • Injector Not on Project Critical Path

13. Summary and Conclusions • Conventional facilities at S20 defined to support Title II • Facilities for two drive lasers • RF design of 120 Hz gun nearly complete • Solenoid design with dipole and quadrupole correctors finished • Pulsed heating solved • Dual RF feed + racetrack full cell • L0-1 accelerator section • RF design finished • Engineering design in progress • RF design review first week of November • Beamline components (magnets) being designed • Drive laser specifications defined in Request for Proposal