July 6, 2022

Current Status

• Accelerator status:
  • Maintenance day, lots of work planned, RF recovery and injector power supply replacement
  • Expect beam restoration to begin late day or into swing shift
    • Probably ~20:00 at the earliest before we get physics quality beam back
    • Unless access still needed, ramp magnets back up and return to beam permit at end of day shift

• Hall Status:
  • SHMS dipole LN2 level was dropping all day yesterday, got low on late swing/early owl
    • Ellen resolved the issue - https://logbooks.jlab.org/entry/4011519
  • Lots of work down in the hall today, issues from yesterday/weekend being resolved
    • HMS water leak
    • SHMS Q2/Dipole LN2
    • HMS Hut laptop

• Experiment status:
  • Currently running Q2=6.00, W=3.19, x=0.39, high ϵ data taking, centre setting - Pion form factor point
  • Progress is slow, ~500 pions an hour (53k target)
    • Revised down to 50k target, 18k pions so far so a while to go yet
  • Rotation to right setting (5.65 degrees) requires an access
    • Can go to left setting first if timing for this is not favourable
  • Some discussion yesterday about the SHMS delta range that is usable - See https://logbooks.jlab.org/entry/4011358 - https://logbooks.jlab.org/entry/4011390 - https://logbooks.jlab.org/entry/4011395
    • Run plan assumed -15 to 20
    • This will make a ~5% or so difference to some settings, much smaller for others
    • My opinion is that we should return to -10 to 20, I'd rather be surprised with extra statistics later as opposed to losing some

Current Run Plan

• PionLT Summer 2022 Run Plan
  • Now on page 66
    • Will be here for a while yet
• Physics Status

Notices in Effect for Shift Crew

• Please pro-rate ABU for max current limit in run plan (uA) in beam time accounting. For example, if we receive 15 uA instead of the max_current_limit in the run plan, then the ABU should be: ABU_prorated = 15/(max current limit) * ABU
• Check the HMS/SHMS rates for when production starts, since for Heep coin. production SHMS saw higher rates. Make sure shift crew takes snapshot of scalers at every setting
• When analysing LD2 or Al dummy or LH2, please leave the target_mass_amu in the standard.kinematics as that of the proton, but when analysing the data with the pionLT script, specify the target used, as different targets will have different ranges in the cuts when integrating the missing mass peak. Refer to log entry: https://logbooks.jlab.org/entry/4005387 These instructions are given in the pionLT run plan.
• Keep an eye on HMS DC chamber wire maps.
  • Hasn't been an issue for a while, but stay vigilant

Current Issues

• Maintenance day, beam restoration expected end of day shift and into swing
  • Day shift, ramp magnets back up once all work in the hall is done
• Breaker trip in the CH late swing (https://logbooks.jlab.org/entry/4011439) caused some equipment to read weirdly in terms of time - https://logbooks.jlab.org/entry/4011453
  • Probably not a problem, should correct though

Planned Accesses to the Hall

• Maintenance day
  • Lots of work being done in the hall, see hall status and yesterday for all of the plans

Planned Accelerator Configuration Changes

• Beam schedule has us getting a gradient change on Saturday (09/07/22), clearly, this is not going to happen
  • If they raise it in upcoming PD meetings, absolutely not. We need a lot more beam at the current pass/gradient

Special Requests

• We should consider a BCM calibration soon, even if we don't get high currents
  • Dave M reminds me that we could lose the accelerator tomorrow, so we should try and get at least something done on this
• Rotation to right setting (5.65 degrees) requires an access
  • Can go to left setting first if timing for this is not favourable