Slip Stacking October 2 2007 Kiyomi Seiya Fermilab

Slip Stacking October 2, 2007 Kiyomi Seiya Fermilab

Current operation Slip stacking 11 batch slip stacking for Proton Plan Status of beam studies Beam loss Injection kicker gap loss Ramp loss Extraction kicker gap loss 8 Ge. V lifetime loss Summary & Plan

MI 120 Ge. V cycle operations Numi target (MINOS Neutrino experiment) Pbar target (Anti proton production) Booster (h=84) Main Injector (h=588) Tevatron Intensity @injection: 4. 8 E 12 ppp x 7 @extraction: 32. 5 E 12 ppp 8. 5 E 12(Pbar) 24. 0 E 12(Numi) Current operation Bucket # Pbar 0 84 Numi 588

Status of current operations Intensity on Pbar target: 8. 5 E 12 ppp Acceleration efficiency: 95% bunch length @ ext. < 1. 8 nsec after the bunch rotation Slip stacking time < 2 Booster cycles Time Beam intensity RF voltage 1 Booster cycle ~ 66. 7 msec 1 revolution ~ 11 msec Momentum MI cycle ~ 1. 9 sec

Slip stacking procedure (MI has 18 53 MHz RF cavities) ΔE/E RF 2(3 cavities) 110 k. V ΔΦ RF 1(3 cavities) 110 k. V RF recapture(18 cavities) 1 MV

Simulation results on phase space (Vrf= 100 k. V, df=1200 Hz) injection 50 turns 10 turns 20 turns 100 turns 12000 turns

Longitudinal phase space (Vrf= 100 k. V, df=1200 Hz) injection 12000 turns Survivors at injection

Parameters on current operation frequency A Frequency separation: 1400 Hz RF voltage for slipping: 110 k. V for each frequency B RF voltage ** MI momentum aperture +/- 0. 07% = +/-3300 Hz Intensity

Longitudinal acceptance with 110 k. V RF and 1400 Hz frequency separation ~7 Me. V 11. 5 nsec

Injection beam from Booster Mt. range with WCM signal Phase space tomography [Me. V] 40 0 -40 -8 0 8 [nsec] +/- 9. 4 Me. V 7. 2 nsec Longitudinal emittance @ injection ~0. 12 e. V-sec

Beam at recapture Recapture voltage: 1 MV Intensity: 8. 5 E 12 @ Injection Measurement Simulation Longitudinal emittance @ recapture ~ 0. 35 e. V-sec Beam loss ~ 5%

Proton Plan Goal • Intensity @ injection : 4. 3 E 12 ppp x 11 @ extraction: 4. 5 E 13 ppp • Total beam power: 400 k. W 80 k. W Pbar 320 k. W Numi • MI cycle rate < 2. 2 sec • Total beam loss: < 5% Current operation Multi-batch operation Bucket # 0 Pbar 7 batches Numi 11 batches Pbar 84 Numi 588

11 batch Slip stacking Frequency A 11 10 Df = 1425 Hz Frequency B 5 3 Intensity RF voltage 1 6 7 8 9 4 2 Slipping with 100 k. V rf Recapture with 1 MV rf

11 batch slip stacking on mixed mode cycle Numi (9) Time 11 msec (1 revolution) Pbar (2)

Status of 11 batch slip stacking Mixed mode cycle • Intensity: 8. 2 E 12 ppp (pbar) 30 E 12 ppp (Numi) • Cycle efficiency ~ 95. 5% MI Intensity record • Intensity: 46 E 12 @ 120 Ge. V Beam loss issues • Injection kicker gap loss • Ramp loss • Extraction kicker gap loss • 8 Ge. V lifetime loss Intensity from Booster Intensity in MI

Injection kicker gap loss (2) Longitudinal simulation for 11 batch slip stacking +40 Me. V 6 -40 Me. V 9 7 10 8 0 11 588 buckets

Ramp loss Acceleration from 8. 9 Ge. V to 10 Ge. V Before acceleration After acceleration +200 Me. V 0 -800 Me. V 0 588 buckets

Simulation for Injection kicker & Ramp losses (1) Longitudinal phase tomography with measurement results 1. 77 E 12 ppp 2. 65 E 12 ppp 3. 44 E 12 ppp +/-1. 68 nsec +/-7. 62 Me. V +/-1. 78 nsec +/-8. 99 Me. V +40 Me. V 0 -40 Me. V -9 nsecc 0 Df: +/-1. 47 nsec Dp/p: +/-6. 88 Me. V +9 nsecc

Simulation for Injection kicker & Ramp losses (2) Comparison between measurements and simulation Simulation Measurement No transverse effects in the simulation.

Extraction kicker gap loss Wall current monitor signal @ extraction Simulation

Summary and Plans Slip stacking is in operation for pbar stacking since December 2004 and increased proton intensity on target by 70%. 11 batch slip stacking scheme have already verified. Beam was sent to Pbar and Nu. MI target: Intensity ; 8. 2 E 12 (Pbar), 30 E 12 (Numi). Efficiency: 95. 5%. Record intensity: 4. 6 E 13 ppp accelerated to 120 Ge. V. Beam loss issues injection kicker loss ramp loss extraction kicker loss Require small emittance beam from Booster. Anti-damp beam on ext. kicker gap with bunch by bunch damper. 8 Ge. V lifetime loss Lower chromaticity with damper.