1. 1 Design of Proton Driver for a Neutrino Factory W. T. Weng Brookhaven National Laboratory NuFact Workshop 2006 Irvine, CA, Aug/25, 2006

2. 2 Outline Examples of parameter dependence Possible design parameter phase space Improvements on existing designs and example of new design Summary and Conclusions

3. 3 Considerations of parameters - I To deliver 4 MW beam power on target, we consider the effects of 1.Energy 2.Repetition Rate 3.Intensity 4.Bunch Length Of the Proton Driver

4. 4 Proton per pulse required for 4 MW 10 Hz25 Hz50 Hz 10 GeV250 × 10 12 100 × 10 12 50 × 10 12 20 GeV125 × 10 12 50 × 10 12 25 × 10 12

5. 5 Process mesons through Cooling Analysis II Post Cooling Count mesons within acceptance of 30π mm

6. 6 Post-cooling 30π Acceptance

7. 7 Summary For Negatives the peak occurs for 6 Gev < Proton KE < 11 GeV For Positives the peak occurs for 9 Gev < Proton KE < 19 GeV Consensus: 10 GeV is a good place to start

8. 8 Target/Beam Baseline used for comparison

9. 9 1 MW Proton Driver - Temperature Issues Power and Heat removal capacity from target go hand-in-hand

10. 10 1 MW/50 Hz PD – target peak stresses 3ns – 30ns – 300ns – 600ns

11. 11 SUMMARY of Performance 1 MW/50 Hz 12.0 e+12 ppp YES 4 MW/50 Hz 48.0 e+12 ppp NO 1 MW/200 Hz 3.0 e+12 ppp YES 4 MW/200 Hz 12.0 e+12 ppp MAYBE

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13. 13 Design Parameter Phase Space 1.8.0 GeV < Energy < 20.0 GeV 2.Rep Rate ~ 50(25) Hz 3.Intensity 50*10**(12) ppp, at 10(20) GeV ( very difficulty with solid target ) 4. Bunch Length < 3 ns, for longitudinal acceptance 5. Cost ???

14. 14 Examples of Future Improvements 1.Power Upgrade of J-PARC 2.Bunch Length of BNL 3.New Design of RAL 4.FFAG

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19. 19 Short Bunch Length at BNL Longitudinal space charge force Experience for MECO Bunch length at transition energy Scale to new intensity and harmonic no.

20. 20 2 MW AGS Proton Driver AGS proton driver layout for alternate injector linac design.

21. 21 Typical variation of ,  R, and  E as the beam energy increases.

22. 22 Longitudinal Space Charge sc parameter, scaling relation, (E. Courant, 1968)

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24. 24 Longitudinal phase space of the proton beam before, at, and after crossing the transition energy in the AGS obtained with the computer code TIBETAN.

25. 25 Expected fractional beam loss upon transition crossing as a function of the initial (95%) longitudinal beam area obtained with the computer code TIBETAN.

26. 26 One Method of generating Short Bunch Short bunch can be generated by compressing RF system It can also be generated by bunch rotation in the ring, or in the external beam line We try to do it by getting to transition energy at extraction( lower voltage ) ( C. Prior showed RAL methods at ISS )

27. 27 AGS as a Proton Driver

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31. 31 Summary and Conclusions We have presented the parameter constraint for the Proton Driver A preferred parameter phase space has been identified. Examples of new design and improvements on existing PD have been shown.