1. 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

2. 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

3. 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

4. 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

5. 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

6. 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

7. 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

8. 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

9. 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

10. 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

11. 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