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Plan of EMMA commissioning 3 shifts in Run #3. Shinji Machida o n behalf of the beam commissioning team ASTeC /STFC/RAL 22 July 2010. Beam time. Run #1: 20-23 June 2010 Run #2: 12-15 July 2010 Run #3: 27-29 July 2010 Run #4: 4-6 August 2010 (full ring)
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Plan of EMMA commissioning3 shifts in Run #3 Shinji Machida on behalf of the beam commissioning team ASTeC/STFC/RAL 22 July 2010
Beam time • Run #1: 20-23 June 2010 • Run #2: 12-15 July 2010 • Run #3: 27-29 July 2010 • Run #4: 4-6 August 2010 (full ring) • Run #5: 12-15 August 2010 full ring • (Run #6: 18-24 August 2010) • Run #7: 30 August – 2 September 2010 rf available • Run #8: 7-10 September • Run #9: 15-18 September • Run #10: 24-26 September • Run #11: 2-3 October • Run #12: 10-13 October
Plan backward • At the end of Run #5 (15 August), • A full lattice which accepts a fixed momentum beam from 10.5+a to 20.5-b [MeV/c]. • Know time of flight in that momentum range. • At the end of Run #4 (6 August), • Know a way to injection a beam for some equivalent momentum range. • Measure cell tune vs relative momentum. • At the end of Run #3 (29 July), • Understand injection orbit for fixed momentum.
Four main lattice parameters (1) • We do not know calibration factor of strength and position of QD and QF. • With fixed QD/QF ratio, strength of QD and QF is equivalent to beam momentum. • Cell tune is sensitive to strength of QD and QF, but insensitive to position.
Four main lattice parameters (2) • With fixed QD/QF ratio (as designed) • Injection a beam. • Minimize betatron oscillations with septum and kickers. • Measure cell tune. • (Measure time of flight.)
Four main lattice parameters (3) • Change strength of QD and QF keeping QD/QF fixed • Injection a beam. • Minimize betatron oscillations with septum and kickers. • Measure cell tune. • (Measure time of flight.)
Four main lattice parameters (4) • Previous procedures give • Cell tune vs “relative” momentum. • Time of flight vs “relative” momentum. • Notice we never know absolute measure of x-axis (momentum). • This is not because we use “equivalent” momentum beam. • This is because we do not know calibration factor of strength and position of QD and QF.
Four main lattice parameters (5) • Determine absolute momentum by looking at cell tune experimentally. • With the fixed range of momentum, change position of QD and QF to obtain desired time of flight curve. • If we do not have a good solution, back to the beginning and try another QD/QF ratio.
From previous measurements (1)kicker • Measured kicker-1 strength agrees with design. • Polarity is correct (kick outside.) • No information on kicker-2. • Assume calibration is correct (same as kicker-1). • Check polarity by BPM1 in S03.
From previous measurements (2)septum • Measured (x, x’) at the exit of septum varies. However, this may be because (x, x’) at the entrance is not the same. • Do the measurement vs strength again with the same initial (x, x’), namely the centre of two quadrupoles. • No re-cabling is required up to here.
Task in Run #3 (1)Understand injection • BPM re-cabling: BPM1 in S03, S04, S05, S06, S07, S08, S09. Sxx is Yuri’s naming at May 2009 commissioning meeting. • Use kicker 1 and 2 only to minimize betatron oscillations.
Task in Run #3 (2)Measure cell tune and tof • With minimized betatron oscillations, measure time of flight. • With small betatron oscillations, measure cell tune.
Task in Run #3 (3)Initial setting • QD/QF: 260/220 A, based on Ben’s measurement. • K1/K2: -34.5/-40.7 mT, 45 mT corresponds to 6.6 V(?) • Septum: based on the repeated measurement.