Difference between revisions of "D2n kinematics"

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(Run Plan 2020)
 
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= Run Plan (updated when needed) =
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= Run Plan 2020 =
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<span style="font-size:200%">Updated Page is here: [[d2n Run Plan 2020]]</span>
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= Run Plan (old notes/no longer current) =
 
*; [https://docs.google.com/spreadsheets/d/1NCFehy_w7i-dfH9_Mgn403ec1e-D3Kqb1D2_muhI8FM/edit?usp=sharing Draft d2n Run Plan]
 
*; [https://docs.google.com/spreadsheets/d/1NCFehy_w7i-dfH9_Mgn403ec1e-D3Kqb1D2_muhI8FM/edit?usp=sharing Draft d2n Run Plan]
 
** '''NOTE''': The SHMS + HMS kinematic pairings are different that what we were planning when those tables were constructed.  We are starting with '''HMS Kin C''' and SHMS Kin X.
 
** '''NOTE''': The SHMS + HMS kinematic pairings are different that what we were planning when those tables were constructed.  We are starting with '''HMS Kin C''' and SHMS Kin X.

Latest revision as of 16:02, 17 August 2020

Run Plan 2020

Updated Page is here: d2n Run Plan 2020

Run Plan (old notes/no longer current)

  • Draft d2n Run Plan
    • NOTE: The SHMS + HMS kinematic pairings are different that what we were planning when those tables were constructed. We are starting with HMS Kin C and SHMS Kin X.
  • Updated rate and yield estimates for kinematics and beam energies below (March 19, 2020) [W. Korsch]

Rough / High-level sketch of d2n kinematic settings

Reduced kinematics list to accommodate limited beam time (dropped 1/4 of kinematics)

      ---------  Beam Params ----------
            E_beam = 10.4 GeV/c
            I_beam = 30 uA
            P_targ = 0.50
            P_beam = 0.80
          ---------  HMS ----------
       E'    theta    x        Q2       W
 A    -4.2   13.5     0.207    2.414   3.178
 B    -4.2   16.4     0.305    3.554   2.993
*C    -4.0   20.0     0.418    5.018   2.806 [Starting here] --  Only setting compatible with SOLID Cherenkov small-angle test.
          --------- SHMS ----------
       E'    theta    x       Q2      W
*X    -7.5   11.0     0.527   2.866   1.859  [Starting here]
 Y    -6.4   14.5     0.565   4.240   2.036
 Z    -5.6   18.0     0.633   5.701   2.046


  • Not shown is the 1-pass running (3'ish days)


Schedule Overview

  • We should expect to have 6 weeks of beam
    • Hall C will have priority over Hall A (if there are beam loading, machine stability issues)
  • Rough priorities:
  1. We plan to start at 5-pass with kinematics A and X (small angle)
    We will start at 5-pass with kinematics C and X (small angle on SHMS, large angle on HMS)
    • This will allow the SOLID Cerenkov prototype folks to setup before beam and run their small-angle test on the HMS side.
  2. Then move to kin A and Z (high-Q2 SHMS, small angle HMS)
  3. Scheduling of Kin B, Y and 1-pass running would depend on how the Accel/target/virus behaves

More Detailed Plan for when beam is handed to us (as of Sunday, August 2)

- Moller measurement will be done on first available day shift -- looks like Monday DAY at this point

- Sanity check beam positions, harp profiles and convince ourselves the tune is still good (no need for Carbon Hole study unless something is really strange) - Ion Chamber calibrations (if not done already)

 - Reference cell filled with N2 @ 10 Atm
 - Carbon Optics

- If the target is still pumping up, or if there are any concerns about the 'real' beam polarization, then

   - Reference cell runs:  2 beam-hours each  (skip He3 for now)
     - N2 @ 10 Atm
     - H2 @ 10 Atm
     - Empty / Vacuum

- Then move into production running:

 HMS Kin C, SHMS Kin X  (Total time:  125 PAC hours, ~10 calendar days)
 - Flip IHWP every 4--8 hours
 - Ensure Charge Asym Feedback is running/working
 - Take NMR meas. every ~5 hours
 - Target:  Transverse
   - Flip target spin at 36 hours
   - 3-4 calendar days in, switch target to Longitudinal
 - Target:  Longitudinal
   - Flip IHWP at 1/2 way into each run block (~4 hours)
   - ~11 hours @   0deg
   - ~11 hours @ 180deg
 - Switch back to Transverse
 - Target:  Transverse
   - 3-4 calendar days until Kin C/X are done
   - Flip target spin at 36 hours in
 - Reference cell runs
   - Complete N2, H2, empty ref cell runs not completed yet (may be used as fill after a target spin flip/rotation)
   - He3 @ 10 hours (2 beam-hours) -- Do this once at the end of this kinematic

- This should take roughly 10 calendar days. - We'll then move to 1-pass for 3 days, then back to 5-pass and follow the above prescription for the remaining Kin A/Z, Kin B/Y

Non-"production" runs

  • Optics are generally in good shape, but we will should take more for HMS kin B (4.2 GeV/C @ 16.4 deg)
    • Analyze and get the new matrices in the analyzer
    • Make sure we have empty target runs for all kinematics help disentangle beamline window contributions
  • Nail down estimates for ref cell running (N2, H2, 3He, empty)
  • Minimal/no positron running?
    • Perhaps measure the positron background in HMS at 13.5 degrees (Kin A) and compare with model as a sanity check? If it matches model, then we can skip the rest?


1-pass running considerations

  • Request pass change to 1-pass
    • Controlled Access to install collimator (RadCon)
    • Check on EPR photo-diode status (replace if needed)
    • Simona will be doing some SOLID Cherenkov work during this time as well
  • Restore 1-pass beam to Hall
    • Moller measurement ASAP
    • Turn off hodoscope bars as before: HMS [1]; SHMS [2]
    • For raster need to have MCC click on the button on the Expert page for 1 coil ( instead of 2 coils). Then need to be sure that to use the "gbeam_pass1_jan2020.param" is being used for analysis.
  • Begin production running following A1n 1-pass notes 1-pass_calibration_for_A1n_(Jan_2020)
  • 3He elastic and QE longitudinal Asymmetries (incl. pressure curve / ref cell running)
    • HMS setting: 11.7 deg, -2.1483 GeV/c
    • SHMS setting: 8.5 deg, -2.12860 GeV/c
  • Polarized 3He Delta Transverse Asymmetry
    • HMS setting: 11.7 deg, -1.75830 GeV/c (electron W=1.232)
    • SHMS setting: 8.5 deg, -1.79736 GeV/c (electron W=1.232)
  • Pol 3He Elastic Measurement (E12-06-121A)
    • Details Coming Soon