JLEIC Ion Integration Goals Near-term goals: Determine workability of baseline bunch formation scheme Confirm parameter calculations from Jiquan Evaluate longitudinal beam parameters and RF requirements Document self-consistent beam and lattice parameter sets through ion complex Initiate Booster injection simulations with space charge Bound booster injection efficiency  ion source requirements Longer-term goals: Initiate impedance and instability budget evaluation  impedance budget, feedback system requirements (if any) Document injector complex accelerator cycle  power supply, RF requirements

Progress Since Last Update Bunch Formation: Booster (Todd) Booster h=1 bunching simulated 30 kV RF with constant voltage after bunching Further Booster ramp design Initial ramp: 280 MeV to 2 GeV (DC cooling) Booster Space Charge (Ed) Anomalous emittance growth from chromatic resonance crossing Reduced momentum spread by 1-2 orders of magnitude Transverse emittance growth x5-8 at 280 MeV injection x1.5-2 at 2 GeV DC cooling porch None visible at 8 GeV extraction

Booster h=1 Bunching Start: coasting beam Gaussian End: 30 kV h=1 bunched Initial Gaussian E distribution: RMS sE/E = 3.1e-3  5.4e-3 100 ms linear RF voltage ramp to 30 kV > 99% capture efficiency (10k macroparticles) Close to parabolic

Booster Ramp Design 30 kV RF dB/dt(max) = 1 T/s d2B/dt2(max) = 5 T/s2 Sync phase = 4 degrees frf=700 to 1030 kHz dB/dt(max) = 1 T/s d2B/dt2(max) = 5 T/s2 200 ms to get to max dB/dt

Booster Cooling Porch Phase Slip Booster phase slip 6x smaller at 2 GeV cooling porch Fractional momentum spread also considerably smaller Probably should evaluate rebunch after DC cooling carefully

Booster h=1 Bunching and Ramping Next steps Develop consensus injection energy spread with Ed/ANL Larger is better; will probably fill momentum aperture anyway Determine how fast RF can be ramped to 30 kV Dynamics, RF control, beam loading Depends on momentum spread: larger is also better Advantageous slip factor Determine how fast d2B/dt2 can be for acceleration ramp start Start ramping during RF ramping for bunching? Turn on injection longitudinal space charge compare to Synergia

Bare chromaticities: (-13.9, -11.5) Booster Space Charge Time Energy Injection KE=280 MeV g=1.3 b=0.64 Cooling KE=2 GeV g=3.1 b=0.95 Extraction KE=8 GeV g=9.5 b=0.99 Ramping Not to Scale RMS Emittance (m) Ramping Horizontal Vertical 1.4e-5 7e-7 1.064e-7 Horizontal Vertical Horizontal Vertical 300 turns 5000 turns 1.059e-7 2500 turns Working point: (7.571, 5.493) Bare chromaticities: (-13.9, -11.5) (Future work will correct to a few negative units, per JPARC MR experience) Ed Nissen

Anomalous Booster Emittance Growth Horizontal Vertical Horizontal Vertical Initial working point (7.571, 5.493) was causing chromatic resonance crossings. The chosen remedy was to reduce the energy spread in the input files. Ed Nissen

Emittance growth by factors x5-8 Booster Injection Injection KE=280 MeV g=1.3 b=0.64 Emittance growth by factors x5-8 1.4e-5 Horizontal Vertical 300 = 430 us δp/p= 4.64x10-2 →4.64x10-4

Emittance growth by factors x1.5-2 Booster Cooling Cooling KE=2 GeV g=3.1 b=0.95 Emittance growth by factors x1.5-2 7.0e-7 5000 = 4.84 ms δp/p= 8.72x10-3 →8.72x10-4

Booster Extraction δp/p= 2.60x10-3 →2.60x10-4 Extraction KE=8 GeV g=9.5 b=0.99 No emittance growth 1.064e-7 1.059e-7 2500 = 2.3 ms δp/p= 2.60x10-3 →2.60x10-4