Improvement of Bdot timing jitter Flat injection Kiyomi
Improvement of Bdot timing jitter & Flat injection Kiyomi Seiya, Chandra Bhat, Salah Chaurize, George Krafczyk, Howie Pfeffer, Bill Pellico, Kent Triplett, Cheng-Yang Tan PSP meeting 31 January, 2019
Booster injection field 15 Hz operation Injection: ~ 40 msec Capture: ~200 msec Orbit excursion: 2 mm 2 K. Seiya et al. | Improved Bdot timing jitter & Flat injection PIP-II 20 Hz operation Injection: ~ 600 msec Orbit excursion : 5 mm 1/31/2019
Symmetric field compensation for present 15 Hz operation with 48 dipole correctors B field error ~1% can be compensated. 400 Me. V Injection 4, 2150 E-02 9, 5800 E-01 4, 2100 E-02 9, 5700 E-01 4, 2050 E-02 9, 5600 E-01 4, 2000 E-02 9, 5500 E-01 4, 1950 E-02 9, 5400 E-01 4, 1900 E-02 9, 5300 E-01 4, 1850 E-02 9, 5200 E-01 4, 1800 E-02 -5, 00 E-04 -3, 00 E-04 -1, 00 E-043, 00 E-045, 00 E-04 P[Ge. V/c] B_ave[T] 5 10 4 8 3 6 2 4 1 2 0 -0, 0005 -1 -0, 0003 -0, 0001 0, 0003 0 0, 0005 -2 -2 -4 -3 -6 -4 -8 -5 -10 Axis Title Icorr[A] Slew rate [Tm/s] 9, 5900 E-01 Corrector current [A] 4, 2200 E-02 average B [T] P [Ge. V/c] 9, 6000 E-01 Corrector current and slew rate d(BL)/dt The required maximum current is 0. 83[A] and the slew rate is 3. 00 [Tm/s] which is less than the maximum slew rate 3. 24[Tm/s] we can handle with the present system. 3 K. Seiya et al. | Improved Bdot timing jitter & Flat injection 1/31/2019
Effect on beam orbit with +/-1 A corrector current Corrector current Orbit difference Corrector current : +/- 1 A Orbit change < 1 mm 4 K. Seiya et al. | Improved Bdot timing jitter & Flat injection 1/31/2019
Asymmetric field compensation Total Int B dl for 2 bending magnet Int B dl for 1 corrector magnet Smooth transition from flat injection field to acceleration field 5 K. Seiya et al. | Improved Bdot timing jitter & Flat injection 1/31/2019
Field correction using cogging board or 473 card Correcto r current [A] Cogging + Icorr[A] Cogging 48 horizontal dipole correctors Icorr[A] 473 card Correcto r current [A] + Icorr[A] 1/31/2019 6 K. Seiya et al. | Improved Bdot timing jitter & Flat injection
Setup of the compensation system at Booster LL room 48 horizontal dipole correctors 473 card Cogging 7 K. Seiya et al. | Improved Bdot timing jitter & Flat injection 1/31/2019
Corrector current sent from 473 card Current set on 473 Current plays on correctors 70 usec delay due to the PS bandwidth 8 K. Seiya et al. | Improved Bdot timing jitter & Flat injection 1/31/2019
Amplitude and timing jitters on B field 1 mm /div Vertical Horizontal Amplitude jitter: ~103 +/- 0. 05 [A] ( ~103 +/- 0. 1 [A] daily) beam orbit at injection varies +/- 1 mm from pulse to pulse Timing jitter: +/- 3 usec ( +/- 20 usec) 9 K. Seiya et al. | Improved Bdot timing jitter & Flat injection 1/31/2019
Improvement of timing jitter between BDOT and BOOSTER Reset Event BDOT: B field minimum Booster reset event $10: reference for beam injection B_dot B_field BDOT timing jitter RESET DELAY = 30990 usec $10 T 1 T 2 $10 10 K. Seiya et al. | Improved Bdot timing jitter & Flat injection T 3 +/- 20 usec T_avg - N +/- 3 usec RESET DELAY = 1026 usec 1/31/2019
BDOT signals triggered with Booster reset events 20 usec /div +/- 20 usec 11 K. Seiya et al. | Improved Bdot timing jitter & Flat injection 2 usec /div +/- 3 usec 1/31/2019
Beam studies on $17 Corrector current 100 usec /div Frequency curve 200 usec /div 12 K. Seiya et al. | Improved Bdot timing jitter & Flat injection B field (Transductor) 1/31/2019
Operation status of flat injection ( on operational cycles) BDOT Frequency curve B field (Transductor) 100 usec /div 13 K. Seiya et al. | Improved Bdot timing jitter & Flat injection -200 usec: Beam Injection -160 usec: End of injection -15 usec: Notch creation RF Feedback ON 0 sec: BDOT 1/31/2019
Optimization of the corrector current and timing Corrector 0. 83 A WCM (beam) BDOT 14 K. Seiya et al. | Improved Bdot timing jitter & Flat injection RPOS (Horizontal BDOT Position) 1/31/2019
Orbit difference with and without correction With compensation HL 16 w/o compensation HS 16 BDOT 200 usec • Orbit difference was much larger ( > 4 mm) than the estimation( < 2 mm) • Field compensation current was 0 A at 200 usec later than we expected • Eddy currents might delay the B field 15 K. Seiya et al. | Improved Bdot timing jitter & Flat injection 1/31/2019
Measurement of the Eddy current effect without Beam pipe Bdot in magnet WITHOUT beam pipe voltage on magnet with beam pipe Current on magnet w/o beam pipe Current on magnet with beam pipe with Beam pipe Bdot in magnet WITH beam pipe voltage on magnet with beam pipe Current on magnet w/o beam pipe Current on magnet with beam pipe 200 usec/div 16 K. Seiya et al. | Improved Bdot timing jitter & Flat injection 1/31/2019
Plan • Asymmetric field compensation with 473 card – Optimize timing including eddy currents – Optimize frequency curve • Realtime field compensation with cogging card • GMPS regulation – Reduce amplitude and timing jitter – Feedforward – LDRD for GMPS regulation with ML was approved 17 K. Seiya et al. | Improved Bdot timing jitter & Flat injection 1/31/2019
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