DC Injector and Space Charge Simulation Status Colwyn Gulliford, Injector Team

Injector work to date (Dec 2016): Injector Status Injector work to date (Dec 2016): Installed in CBETA experimental hall All subsystems tested Initial beam recommissioning

Laser 50 MHz System: 3 ps pulse length 10 Watts ~350 fs rms jitter 10 µm rms pointing stability Tunable Duty Factor: 5E-6 – 1 Longitudinal Shaping

Cathodes Cathode Growth Chamber Cathode Load Lock System Example QE Scan of Offset Cathode for High Current Operation Cathode Characterization

DC Electron Source Status Work to date: Moved from Electron Source Development Lab Installed in final position Baked HV Conditioned

DC Electron Source Status Work to date: Moved from Electron Source Development Lab Installed in final position Baked HV Conditioned Completed Sept 2016, Stable Operation at 350 kV

DC Electron Source Status Work to date: Moved from Electron Source Development Lab Installed in final position Baked HV Conditioned Completed Sept 2016, Stable Operation at 350 kV

Injector Cryomodule (ICM) Status ICM Work: Installation June 2016 Cool down to 4K (6/9/2016) System check at 2K (6/15/2016) ICM is fully tested and ready for RF power (October 2016) Currently operating at 2K (Jan 2017) Active pumping of Insulation Vacuum Vessel Active pumping of beamline UHV Input coupler N2 purge while ICM is idle (RF off) Tested with beam up to 1000 kV/cavity (Dec 2016)

Beamline Components Beamline Installed (Summer 2016) Dump Temperature Diagnostics Calibration Buncher Processed (10/13/2016)

Beam Running Summary of results Target, min. Achieved Cathode: 1% QE, offset 3% Gun: 350 kV 350 kV ICM: 1 MeV / cavity 1 MeV - CBETA needs further conditioning Laser: 5 W @ 50 MHz 10 W Current: 1 mA 4 mA Achieved all necessary goals for this phase, ran out of time for push to UPP current

Current Activities Currently Main Linac Cryomodule (MLC) is being prepared to move to it’s final location for the MLC beam test (Wed)

Current Activities Currently Main Linac Cryomodule (MLC) is being prepared to move to it’s final location for the MLC beam test (Wed) For the injector: Disassembly of diagnostic/dump sections New switchyard and merge beam pipe Building 4 additional magnets Installation of (B1) merger Installation of (B2) diagnostic line

Current Activities Currently Main Linac Cryomodule (MLC) is being prepared to move to it’s final location for the MLC beam test (Wed) For the injector: Disassembly of diagnostic/dump sections New switchyard and merge beam pipe Building 4 additional magnets Installation of (B1) merger Installation of (B2) diagnostic line

Space Charge Simulations Optimize with (3D) space charge in GPT to match specified beam sizes and divergence at the end of the first pass of MLC.

Space Charge Simulations Parameter Optimization Range 125 pC Example Solution Gun Voltage 400 kV Buncher Voltage/Phase (0, 90] kV / - 90 deg 73 kV / -90 deg SRF 1 Voltage/Phase (0, 1800] kV / [-45, 45] deg 870 kV / -6 deg SRF 2 Voltage/Phase 1722 kV / 3 deg SRF 3 Voltage/Phase 1493 kV / 13 deg SRF 4 Voltage/Phase 1052 kV / -26 deg SRF 5 Voltage/Phase 822 kV / -33 deg Solenoid 1 Current (0, 6] Amps 4 Amps Solenoid 2 Current 2.5 Amps A3 Quad Currents [-10, 10] Amps (0.2, 0.3, 1.2, -3.5) Amps B1 Quad Currents (4.3, 4.3, -0.9) Amps MLC Cavity Voltages/Phases 6 MV / (-2, 0, 0, 0, 0, 0) deg 125 pC

Space Charge Simulations Parameter Optimization Range 25 pC Example Solution Gun Voltage [300, 400] kV 350 kV Buncher Voltage/Phase (0, 90] kV / - 90 deg 49.5 kV / -90 deg SRF 1 Voltage/Phase (0, 1800] kV / [-45, 45] deg 1122 kV / -9 deg SRF 2 Voltage/Phase 1791 kV / 4 deg SRF 3 Voltage/Phase 1576 kV / 16 deg SRF 4 Voltage/Phase 834 kV / -33 deg SRF 5 Voltage/Phase 426 kV / -15 deg Solenoid 1 Current (0, 6] Amps 3.7 Amps Solenoid 2 Current 2.4 Amps A3 Quad Currents [-10, 10] Amps (0.1, 0.4, 1.5, -3.6) Amps B1 Quad Currents (4.9, 3.1, -0.7) Amps MLC Cavity Voltages/Phases 6 MV / (-2, 0, 0, 0, 0, 0) Deg 6 MV / (-2, 0, 0, 0, 0, 0) deg 25 pC

Summary Optimized Space Charge simulations performed Have KPP ready injector settings from simulations Injector rebuilt/recommissioned Reached KPP current, energy slightly lower than design Preparing for MLC beam tests