Weekly Review of Operation Recycler departmental meeting May

Weekly Review of Operation Recycler departmental meeting May 30 th, 2007

Agenda § Machine status § Phase trombone program upgrade (Meiqin, 30 min) § Schottky tomography (Alexey, 15 min) 2

Status Summary – Transfers from Accumulator § Pbars to the Recycler Ø 39 Shot setups • 1762 E 10 Pbars extracted from the Accumulator (in MI) – Assuming ‘Historical’ MI to RR efficiencies (i. e. 95%): 1674 e 10 – Last week: 1738 e 10 » Average efficiencies Historical – ACC to MI » ‘Storage’ Last week This week 95% 93% 97% XX% 85% 82% (in/out measured in MI) Did not take into account ‘storage cycle’ where we lost 265 e 10 • for that cycle: Storage efficiency was 24% 3

Pbar Monthly Totals 4

Status Summary – Shots to Te. V § Pbars to the Tev Ø 5 shot setups: 1160 E 10 transferred (measured in MI) Only 203 e 10 if remove one large store • 232 e 10 Average Intensity per shot – Last week: 241 e 10; 2 months ago: 300 e 10 Ø Average emittances – Trans. Schottky (in RR)* – Trans. FW (in RR) * [p mm mrad] – Longitudinal (in RR) * – Long. (bunch in MI) [e. V s] • Average mining efficiency : Last week 4. 9 2. 1 59 1. 0 This week 4. 8 1. 8 55 0. 9 Note: I am now taking the average of all the bunches 96% * Before mining 5

Operational Highlights and Machine Maintenance § Recyler Ø Tried to induce vacuum burst in R 32 line once more • Still unsuccessful • Sacrificed 13 e 10 and fired TSPs – Only slight improvement § Ecool Ø Sublimated TSPs under the Pelletron Ø Perfect running week • No (unprovoked) recirculation interruptions 6

Issues - Recycler § Lost one transfer on MI abort during pbar load Ø Indirect effects from Mini. Boone losses • Tried to implement change to ACL script to turn off Mini. Boone when ‘actually’ loading pbars – MI personnel is looking into more permanent and robust solution § Lost two stashes successively (150 e 10 & 100 e 10) Ø Replaced Camac 465 ramp card after the first loss • Probably not the issue Ø Still do not know what happened exactly • Suspect: MECAR • More diagnostics are being implemented § Lost 15 e 10 on MI PS loop trip Ø Too large an error for QCL to correct • Tripped Ø Did not loose any beam on the other loop trips 7

Issues - Ecool § Pelletron Safety System trip Ø No beam • Likely tripped because the chain current went beyond 132 m. A Ø Probable temporarily ‘burst’ of discharges in the gas • Safety System does work ! 8

Studies highlights § Cooling efficiency with the electron beam off axis Ø Now have ‘standard’ data for 0, +1, +2 and +3 mm offset § Effect of moving barriers on momentum distribution (this morning) Ø Check/Gain experience with Paul’s tomography program Longitudinal emittances evolution (as measured by Paul’s program) 95% 90% ‘Shake’ beam (i. e. move bucket #7 back and forth) 68% Beam going DC 9

Plan/Upcoming studies § Near term Ø Measure and calibrate cavity fan back voltage (Martin, Paul, Chandra) Ø Cooling efficiency off-axis (Lionel, Sasha) Ø Momentum diffusion study (Dan) • Need 100 -200 e 10 Ø New optics implementation (Many…) • Wait for latest data analysis ? (Meiqin) Ø RR dampers update (Jim Crisp, Nathan Eddy) • Still not implemented Ø Adjust compensation loop to new $2 A ramp (Paul Lebrun) • Sometime this week ? 10

Long(er) term studies list § Ecool related (Lionel and/or Sasha and/or Arden) Ø Drag rate measurements Ø Optimize focusing at 190 G Ø Increase beam size in cooling section • First pass not very successful Ø YAG measurements • Beginning of summer shutdown § ‘Old’ items not marked as completed in studies list Ø Rapid pbar transfer scheme (Chandra) Ø Electron cooling in linear bucket (Lionel, Sasha) § Other Ø Standard stochastic cooling rate measurements (Sasha, Lionel, Dan, Cons) Ø Recycler impedance measurement (Martin) 11

Long(er) term studies list (II) § In proton mode Ø R 22 -line dispersion function measurement (Ming-jen) Ø Mapping LAM 222 field (Ming-jen) Ø Characterize Recycler abort (Dave Johnson) • For Nova project Ø IPM data in boomerang mode (Cons) 12

List of work in progress/scheduled to be done § Things I am aware of… Ø Ecool related • Pelletron energy stability improvements (Greg, Kermit) – In progress • Automated energy check/drag rate measurement (Arden) • ACCELNET upgrade (Arden) – Computer in house Ø Recycler related • Understand RF output when buckets are dropped (Martin) – Not a priority • New DCCT check out (Ron Kellet, Jim Crisp) 13