LCLS Injector Update D H Dowell SLAC FAC

LCLS Injector Update D. H. Dowell, SLAC FAC 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 October 12 -13, 2004 Injector Update David H. Dowell dowell@slac. stanford. edu

LCLS Injector Performance Requirements: October 12 -13, 2004 Injector Update David H. Dowell dowell@slac. stanford. edu

LCLS Injector Configuration RF Gun & Solenoid L 0 -1 & L 0 -2 3 -m SLAC Sections Load Lock Gun Diagnostics Laser Heater & Chicane Transverse RF Cavity Electro-Optic Diagnostic Radiation Shield Walls OTR Emittance Diagnostics 35 o Bend SLAC Main Linac Beamline Straight Ahead Spectrometer October 12 -13, 2004 Injector Update David H. Dowell dowell@slac. stanford. edu

S 20 Floor Plan • Cable Plant Specs Defined • Title II Design Started See PRD: Conventional Facilities Specifications For the Sector 20 Alcove October 12 -13, 2004 Injector Update David H. Dowell dowell@slac. stanford. edu

RF Design Progress L 0 -1 Accelerator section Dual feed RF design complete L 0 -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 October 12 -13, 2004 Injector Update David H. Dowell dowell@slac. stanford. edu

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 October 12 -13, 2004 Injector Update David H. Dowell dowell@slac. stanford. edu

Localized Pulsed Heating of RF Coupling Port Gun body stress in Pa • The BNL/SLAC/UCLA gun design has a T of 137 o. C/pulse at the port. • The redesigned port gives a T of 41 o. C/pulse. • NLC designs limit T to 50 o. C/pulse Pulse Heating Analysis: Zenghai Li and Liling Xiao October 12 -13, 2004 Injector Update • Localized heating of the RF coupling port. • The heat flux (watts/m 2) is shown for the gun operating at 140 MV/m and 120 Hz. • Total dissipated power is 3676 watts. ANSYS Analysis: John Hodgson and Nancy Yu David H. Dowell dowell@slac. stanford. edu

L 0 -1 Structure RF Design October 12 -13, 2004 Injector Update David H. Dowell dowell@slac. stanford. edu

L 0 -1 Structure RF Dual Feed October 12 -13, 2004 Injector Update David H. Dowell dowell@slac. stanford. edu

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 October 12 -13, 2004 Injector Update David H. Dowell dowell@slac. stanford. edu

Injector Physics, see breakout • Diagnostics and Commissioning 8% modulation – Gun measurements • Accurate thermal evaluation • Gun spectrometer – 6 D beam characterization at 135 Me. V • Simulations – Low Charge tunings Name 80 r ( 80 5%) Nom. , 1 n. C, 10 ps 1. 2 mm 0. 9 mrad 2. 5 1 n. C, 17. 5 ps 0. 85 0. 75 1. 5 0. 2 n. C, 10 ps 0. 39 0. 38 2. 5 0. 2 n. C, 5 ps 0. 42 0. 37 5 • RF studies – L 01 dual feed, racetrack shape necessary – RF gun dual feed, racetrack shape in full cell – mode 0 studies • 8 MHz mode separation better • klystron pulse shaped October 12 -13, 2004 Injector Update David H. Dowell dowell@slac. stanford. edu

Injector Schedule • Schedule Coordinated with Shutdowns • Over a Year for Injector Commissioning • Injector Not on Project Critical Path October 12 -13, 2004 Injector Update David H. Dowell dowell@slac. stanford. edu

Summary and Conclusions Conventional facilities at S 20 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 L 0 -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 October 12 -13, 2004 Injector Update David H. Dowell dowell@slac. stanford. edu