1. FFAG Studies at BNL Alessandro G. Ruggiero Brookhaven National Laboratory FFAG’06 - KURRI, Osaka, Japan - November 6-10, 2006

2. November 8, 2006A.G. Ruggiero (BNL) -- FFAG'062 of 17 FFAG Studies at Brookhaven South Corner: Muons Palmer, Berg, … North Corner: Protons Ruggiero, Trbojevic Dejan->Medical, Gantry, eRHIC,… Sandro->AGS-FFAG, Neutrino Factory, MA-LE-PD, (RIA, electrons,…)

3. November 8, 2006A.G. Ruggiero (BNL) -- FFAG'063 of 17 AGS-FFAG New AGS Injector for Upgrade to 1-4 MW at 28 GeV Rep Rate2.5 - 5.0 Hz Protons10 14 ppp Circumference809 m FFAGFDF Triplet Non-Scaling Lattice Linear Field Profile LinacFFAG AGS After-Burner 400 MeV 1.5 GeV 20 GeV 40 GeV All in the same AGS Tunnel FFAG Reference Design

4. November 8, 2006A.G. Ruggiero (BNL) -- FFAG'064 of 17 NuFact - Requirements Kinetic Energy5 - 15 GeV11.6 GeV Average Power4 MW 4 MW Repetition Rate50 Hz50 Hz Number of Bunches3 - 55 Bunch Length (rms)1 - 3 ns2 ns Number of Protons4.31 x 10 13 per pulse Protons per Bunch0.862 x 10 13

5. November 8, 2006A.G. Ruggiero (BNL) -- FFAG'065 of 17 Accelerator Architectures Rapid-Cycling Synchrotrons Super-Conducting Linacs FFAG (cyclotrons, RLA, microtrons, …) SCL CEBAF Dog-Bone FFAG The case for a Non-Scaling FFAG A.G. Ruggiero, BNL Report C-A/AP/219, Oct. 2005 also in proceedings of NuFact’06, Frascati, June 2005

6. November 8, 2006A.G. Ruggiero (BNL) -- FFAG'066 of 17 FFAG Accelerators for Proton Driver Single-turn Extraction Single-turn Transfer 400-MeV Injector 3 FFAG Rings 0.4 - 1.5 GeV 1.5 - 4.45 GeV 4.45 - 11.6 GeV Multi-turn Injection FFAG’s are Non-Scaling of about the same circumference and similar structure, located in the same enclosure. Bunch Compression is done in the last ring at the end of acceleration. The scheme allows flexibility of choice of energy, intensity, rep rate. It can suit any requirements for muon production and collection

7. November 8, 2006A.G. Ruggiero (BNL) -- FFAG'067 of 17 Three - FFAG Accelerator Rings (1) Injector Ring * Low-Energy Ring High-Energy Ring Kinetic Energy: Inj. Ext. GeV0.40 1.50 4.45 11.6  Inj. Ext. 0.7131 0.9230 0.9847 0.9972  p/p ±%40.4540.4340.41 Circumferencem807.091817.852828.613 No. of Periods136 Period Lengthm5.9346.0146.093 Harmonic Number757677 RF  = 10.7612 m MHz MHz/ms 19.89 25.69 0.6 26.06 27.78 0.2 28.17 28.50 0.03 * A.G. Ruggiero, “1.5-GeV FFAG Proton Accelerator for the AGS Upgrade”, Invited Talk to EPAC-04, July 6-11, 2004, Lucerne, Switzerland. T a = 10 ms

8. November 8, 2006A.G. Ruggiero (BNL) -- FFAG'068 of 17 Lattice Parameters D FF SS gg Non-Scaling Lattice Injector Ring Low-Energy Ring High-Energy Ring Drifts: S g mmmm 2 x 1.26725 0.30 2 x 1.28588 0.3044 2 x 1.3045 0.3088 F-sector: Length Field min Field max Gradient m kG kG/m 0.70 -0.78409 3.79445 26.5817 0.71029 -1.84918 8.94876 60.8858 0.72059 -4.23518 20.4415 139.476 D-sector: Length Field min Field max Gradient m kG kG/m 1.40 1.83450 -1.39962 -23.2956 1.42058 4.32645 -3.30084 -53.3590 1.44118 9.90888 -7.51787 -122.236  x max, in F in D cm 17.22 13.88 17.46 14.07 17.69 14.26

9. November 8, 2006A.G. Ruggiero (BNL) -- FFAG'069 of 17 Linear Field Distribution (kG vs. cm) Injector Ring High-Energy Ring Low-Energy Ring

10. November 8, 2006A.G. Ruggiero (BNL) -- FFAG'0610 of 17 Lattice Functions Phase Adv. / Cell H V 105.234 o 99.9395 o Betatron Tune, H V 39.755 37.755 Nat. Chromaticity, H V -0.9263 -1.8052 Transition Energy,  T 105.482 i All Rings Linear Field Profile Injection Extraction

11. November 8, 2006A.G. Ruggiero (BNL) -- FFAG'0611 of 17 Tune Variation & Radial Compactness same result for all Rings  = (p - p inj) / p inj F D F Half a Period

12. November 8, 2006A.G. Ruggiero (BNL) -- FFAG'0612 of 17 Three - FFAG Accelerator Rings (2) Injector Ring Low-Energy Ring High-Energy Ring Energy Gain / TurnMeV0.250.501.00 No. of Revolutions440060007200 RF Peak VoltageMVolt0.501.002.00 Acceleration Periodms13.96216.77619.514 Injection Periodms4.924-- Repetition RateHz52.9559.6151.25 Gap VoltagekVolt50 Gaps per Cavity222 No. of Cavities51020

13. November 8, 2006A.G. Ruggiero (BNL) -- FFAG'0613 of 17 Three - FFAG Accelerator Rings (3) Injector Ring Low-Energy Ring High-Energy Ring Protons / Cycle4.31 x 10 13 Average CurrentmA0.345 Average PowerMW0.5171.534.0 Nor. Emittance (full)  mm-mrad 400 Act. Inj. Emittance  mm-mrad 393.3166.870.1 Half Vert. Beam Sizecm6.874.472.90 Half Hor. Beam Sizecm4.432.891.87 Bunching Factor, B  /  √2π 2.04.08.0 rms Bunch Length,  ns7.23.61.8 Tune-Shift0.2720.1270.048 Injection

14. November 8, 2006A.G. Ruggiero (BNL) -- FFAG'0614 of 17 RF Frequency & Power Injector Ring Low-Energy Ring High-Energy Ring MHz MW # turns MW 250 kW/cavity

15. November 8, 2006A.G. Ruggiero (BNL) -- FFAG'0615 of 17 Injector Ring and Injection Injection EnergyMeV400 H – Source CurrentmA35 RFQ Transmission%80 Chopping Ratio%5/75 x 75 Inject. Beam CurrentmA1.4 Inj. Protons / turn0.33 x 10 11 Injected Turns1306 Pulse Lengthms4.924 Duty Cycle0.246 Chopping FrequencyMHz1.326 B1 B2 C1 Foil C2 From DTL Injection Orbit Bump Orbit RF Ion Source ?

16. November 8, 2006A.G. Ruggiero (BNL) -- FFAG'0616 of 17 Extraction and Targetting The Revolution Period at Extraction from the High-Energy Ring T 0 = 2.70 µs Beam Bunches are extracted individually every n turns Pulse Duration n = 1n T 0 = 2.70 µs 10.80 µs 2 5.4021.60 3 8.1032.40 410.8043.20 513.5054.00 Kicker Septum F D F F D F F D F

17. November 8, 2006A.G. Ruggiero (BNL) -- FFAG'0617 of 17 NuFact - Conclusions  FFAG Accelerators for Neutrino Factories are feasible  Issues: Space Charge at Injection Multiple Resonance Crossing Injector Linac (400-MeV DTL or ????) Multi-turn Injection of H – Magnet Feasibility Fast RF sweep (ferrite, RF power) Collimation Numerical Tracking Cost Estimate  It is possible to raise the Repetition Rate --> 1 kHz or CW Mode of Operation (Harmonic Number Jump)