1. PSB magnetic cycle 160 MeV to 2 GeV
PS TFB
PSB magnetic cycle 160 MeV to 2 GeV
New
Full new MPS and bending magnets model supplied by Serge Pittet, Antony Newborough and Fulvio Boattini. (Vmax = 5 kV, Vdot max 1kV/ms, L=0.18H, R = 0.5 Ohm, feedback on acquired current value with dynamic transfer function characterized)
Cavity Voltage limited to 8 kV (to avoid changing the cavity or add extra cavity cells in locations that are anyhow not available. Info from Mauro Paoluzzi)
Simulation with a RMS current increase in the MPS of 10% (no cost at the magnets level)
Simulation with a RMS current increase in the MPS of 30% (only 500k-1 Mchf cost at the magnets level)
Simulation with a cavity current limited to 3 A (present limit, avoids changing the amplifier)
The simulations will take into account 2 beam intensity limits:
Max LHC beam intensity (3.25E12 p per ring, value obtained from Bettina Mikulec)
Absolute max intensity (2.5E13 p per PSB ring)
A. Blas
2 GeV magnetic cycle /06/2010

2. PSB magnetic cycle 160 MeV to 2 GeV
PS TFB
PSB magnetic cycle 160 MeV to 2 GeV
Simplifications
Pure h=1 acceleration and sinusoidal bunch line density (the space charge load should be less with h1+h2) -> overestimation of constraints
Inductive and resistive wall effect neglected (impedance value to be asked for, but practically assumed to be low). The inductive effect counteracts the space charge effect. -> overestimation of constraints
Transverse space charge effects not (yet) estimated
A. Blas
2 GeV magnetic cycle /06/2010

3. PSB magnetic cycle 160 MeV to 2 GeV
PS TFB
PSB magnetic cycle 160 MeV to 2 GeV
Longitudinal space charge effect
Total coupling impedance:
Z0 = 377 Ω
Parasitic voltage superimposed (each turn) to the accelerating voltage (space charge only):
Inductive and resistive wall neglected
Circular beam pipe approximation (real value to be checked for)
A. Blas
2 GeV magnetic cycle /06/2010

4. PSB magnetic cycle 160 MeV to 2 GeV
PS TFB
PSB magnetic cycle 160 MeV to 2 GeV
Longitudinal space charge effect
Parasitic voltage superimposed (each turn) to the accelerating voltage (space charge only):
A. Blas
2 GeV magnetic cycle /06/2010

5. PSB magnetic cycle 160 MeV to 2 GeV with max LHC beam intensity
PS TFB
PSB magnetic cycle 160 MeV to 2 GeV with max LHC beam intensity
Simulation 1: E12 p per ring, injection at 1.2 T/s, 8kV (minus Space Charge), bucket filled up to 80 % (0.99 eV.s)
340 ms acceleration + 15 ms flat-top ( ms presently)
A. Blas
2 GeV magnetic cycle /06/2010

6. PSB magnetic cycle 160 MeV to 2 GeV with max LHC beam intensity
PS TFB
PSB magnetic cycle 160 MeV to 2 GeV with max LHC beam intensity
Simulation 1: E12 p per ring, injection at 1.2 T/s, 8kV (minus Space Charge), bucket filled up to 80 % (0.99 eV.s)
340 ms acceleration + 15 ms flat-top ( ms presently)
A. Blas
2 GeV magnetic cycle /06/2010

7. PSB magnetic cycle 160 MeV to 2 GeV with max LHC beam intensity
PS TFB
PSB magnetic cycle 160 MeV to 2 GeV with max LHC beam intensity
Simulation 1: E12 p per ring, injection at 1.2 T/s, 8kV (minus Space Charge), bucket filled up to 80 % (0.99 eV.s)
340 ms acceleration + 15 ms flat-top ( ms presently)
A. Blas
2 GeV magnetic cycle /06/2010

8. PSB magnetic cycle 160 MeV to 2 GeV with max LHC beam intensity
PS TFB
PSB magnetic cycle 160 MeV to 2 GeV with max LHC beam intensity
Conclusion for the LHC type beams:
The envisaged MPS
The present magnets cooling setup
The present rf cavities with the present amplifiers
Are compatible (with a comfortable margin) with all LHC beams accelerated at 2 GeV
A. Blas
2 GeV magnetic cycle /06/2010

9. PS TFB
FASTEST PSB magnetic cycle with present rf setup 160 MeV to 2 GeV with Absolute max intensity
Simulation 2: 2.5 E13 p per ring, injection at 1.2 T/s, 8kV (minus Space Charge), bucket filled up to 80 % (0.68 eV.s instead of 1 eV.s as planned)
Above the 30% limit
We need to shift the injection<C275
810 ms acceleration + 5 ms flat-top ( ms presently)
A. Blas
2 GeV magnetic cycle /06/2010

10. PS TFB
FASTEST PSB magnetic cycle with present rf setup 160 MeV to 2 GeV with Absolute max intensity
Simulation 2: 2.5 E13 p per ring, injection at 1.2 T/s, 8kV (minus Space Charge), bucket filled up to 80 % (0.68 eV.s instead of 1 eV.s as planned)
810 ms acceleration + 5 ms flat-top ( ms presently)
A. Blas
2 GeV magnetic cycle /06/2010

11. PS TFB
FASTEST PSB magnetic cycle with present rf setup 160 MeV to 2 GeV with Absolute max intensity
Simulation 2: 2.5 E13 p per ring, injection at 1.2 T/s, 8kV (minus Space Charge), bucket filled up to 80 % (0.68 eV.s instead of 1 eV.s as planned)
810 ms acceleration + 5 ms flat-top ( ms presently)
A. Blas
2 GeV magnetic cycle /06/2010

12. PS TFB
FASTEST PSB magnetic cycle with present rf setup 160 MeV to 2 GeV with Absolute max intensity
Partial conclusion:
For the absolute max intensity with the present rf setup
The MPS need to dissipate more power than the actual value + 30 %
The magnetic cycle should last at least 1000 ms and the rf cycle 815 ms
A. Blas
2 GeV magnetic cycle /06/2010

13. PS TFB
FASTEST PSB magnetic cycle with present rf setup 160 MeV to 2 GeV with 2E13 p per ring
Simulation 3: 2 E13 p per ring, injection at 1.2 T/s, 8kV (minus Space Charge), bucket filled up to 80 % (0.76 eV.s instead of 1 eV.s as planned)
630 ms acceleration + 15 ms flat-top ( ms presently)
A. Blas
2 GeV magnetic cycle /06/2010

14. PS TFB
FASTEST PSB magnetic cycle with present rf setup 160 MeV to 2 GeV with 2E13 p per ring
Simulation 3: 2 E13 p per ring, injection at 1.2 T/s, 8kV (minus Space Charge), bucket filled up to 80 % (0.76 eV.s instead of 1 eV.s as planned)
630 ms acceleration + 15 ms flat-top ( ms presently)
A. Blas
2 GeV magnetic cycle /06/2010

15. PS TFB
FASTEST PSB magnetic cycle with present rf setup 160 MeV to 2 GeV with 2E13 p per ring
Simulation 3: 2 E13 p per ring, injection at 1.2 T/s, 8kV (minus Space Charge), bucket filled up to 80 % (0.76 eV.s instead of 1 eV.s as planned)
630 ms acceleration + 15 ms flat-top ( ms presently)
A. Blas
2 GeV magnetic cycle /06/2010

16. PS TFB
FASTEST PSB magnetic cycle with present rf setup 160 MeV to 2 GeV with 2E13 p per ring
Partial conclusion for the 2E13 p beam with the present rf setup:
2 E13 p can be accelerated with the present rf setup
If the Magnets cooling circuit is upgrade to cope with +20% of RMS power
If the cycle duration with beam can be extended to 645 ms (530 ms presently)
A. Blas
2 GeV magnetic cycle /06/2010

17. PS TFB
PSB magnetic cycle with the present rf setup and with the present magnets cooling circuit
Simulation 4: 1.4 E13 p per ring, injection at 1.2 T/s, 8kV (minus Space Charge), bucket filled up to 80 % (0.85 eV.s instead of 1 eV.s as planned)
460 ms acceleration + 15 ms flat-top ( ms presently)
A. Blas
2 GeV magnetic cycle /06/2010

18. PS TFB
PSB magnetic cycle with present rf setup and with present magnets cooling circuit
Simulation 4: 1.4 E13 p per ring, injection at 1.2 T/s, 8kV (minus Space Charge), bucket filled up to 80 % (0.85 eV.s instead of 1 eV.s as planned)
460 ms acceleration + 15 ms flat-top ( ms presently)
A. Blas
2 GeV magnetic cycle /06/2010

19. PS TFB
PSB magnetic cycle with present rf setup and with present magnets cooling circuit
Simulation 4: 1.4 E13 p per ring, injection at 1.2 T/s, 8kV (minus Space Charge), bucket filled up to 80 % (0.85 eV.s instead of 1 eV.s as planned)
460 ms acceleration + 15 ms flat-top ( ms presently)
A. Blas
2 GeV magnetic cycle /06/2010

20. PS TFB
PSB magnetic cycle with present rf setup and with present magnets cooling circuit
Partial conclusion concerning the simulation with no change on the rf, neither on the magnets cooling circuit:
Only 1.4 E13 p per ring can be accelerated
A. Blas
2 GeV magnetic cycle /06/2010

21. PSB magnetic cycle with upgraded h1 rf amplifiers
PS TFB
PSB magnetic cycle with upgraded h1 rf amplifiers
Simulation 5: 2.5 E13 p per ring, injection at 1.2 T/s, 8kV (minus Space Charge), bucket filled up to 80 % (0.681 eV.s instead of 1 eV.s as planned)
460 ms acceleration + 15 ms flat-top ( ms presently)
A. Blas
2 GeV magnetic cycle /06/2010

22. PSB magnetic cycle with upgraded h1 rf amplifiers
PS TFB
PSB magnetic cycle with upgraded h1 rf amplifiers
Simulation 5: 2.5 E13 p per ring, injection at 1.2 T/s, 8kV (minus Space Charge), bucket filled up to 80 % (0.681 eV.s instead of 1 eV.s as planned)
460 ms acceleration + 15 ms flat-top ( ms presently)
A. Blas
2 GeV magnetic cycle /06/2010

23. PSB magnetic cycle with upgraded h1 rf amplifiers
PS TFB
PSB magnetic cycle with upgraded h1 rf amplifiers
Simulation 5: 2.5 E13 p per ring, injection at 1.2 T/s, 8kV (minus Space Charge), bucket filled up to 80 % (0.681 eV.s instead of 1 eV.s as planned)
460 ms acceleration + 15 ms flat-top ( ms presently)
A. Blas
2 GeV magnetic cycle /06/2010

24. PSB magnetic cycle 160 MeV to 2 GeV
PS TFB
PSB magnetic cycle 160 MeV to 2 GeV
Overall conclusion:
The new foreseen MPS circuit with the present magnets cooling circuit and the present rf setup allow for a 1.4E13 p acceleration. This is ok for the most intense LHC beam.
The 1Mchf upgrade of the magnets cooling circuit (+30% dissipation) allows for a 2E13p acceleration as long as the cycle duration with beam can be extended to 645 ms instead of 530 ms as presently.
Without magnets cooling upgrade, 2.5E13 p can be accelerated in 460 ms if the h1 rf amplifier are upgraded to provide 4.8 A + margin instead of 3A as presently.
A. Blas
2 GeV magnetic cycle /06/2010

25. PSB magnetic cycle 160 MeV to 2 GeV
PS TFB
PSB magnetic cycle 160 MeV to 2 GeV
To be done:
Include the transverse space charge effects in the simulation
in order to plot the transverse ΔQ
and estimate transverse losses during the first part of the acceleration
A. Blas
2 GeV magnetic cycle /06/2010