View source for D2n kinematics


= Run Plan (updated when needed) =
* [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.
* Updated rate and yield estimates for kinematics and beam energies below (March 19, 2020) [W. Korsch]
** [[Media:RateUpdate-Korsch_19Mar2020.pdf|Rate Estimate Updates (19 Mar 2020)]] (NOTE: Ignore the ''primed'' kinematics, they are not relevant anymore.)

= 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''' (2--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:
# <strike>We plan to start at 5-pass with kinematics A and X (small angle)</strike>
#; 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.
# Then move to kin A and Z (high-Q2 SHMS, small angle HMS)
# 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) ==

 NOTE: I'm sure this will get tweaked...

- 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 20 degree and compare with model as a sanity check?


=== 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 [https://logbooks.jlab.org/entry/3756736]; SHMS [https://logbooks.jlab.org/entry/3760238]
** 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'''