4 Pass Run Plan

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4-pass run plan

Goal

The goal of the E12-09-017 experiment is to measure the pt-dependence of SIDIS from proton, deuteron, and aluminum targets, for final state pi+, pi-, K+, and K-. The experiments aims to measure absolute cross sections with particular attention to achieving small errors on the ratios of cross sections for different final states and targets. The beam single-spin asymmetry will also be measured at the settings with sufficient phi coverage. The specific goal of the 4-pass run plan is to take repeat several of the 5-pass runs but with a lower beam energy, for the purpose of checking the SIDIS models used for radiative corrections.

Experimental setup

  • Main trigger is 3/4 hodoscopes in HMS in coincidence with 3/4 Hodoscopes in SHMS.
  • HMS is setup for detecting electrons (inclusive DIS measurement).
  • SHMS is setup for detecting charged pions and kaons (semi-inclusive DIS measurement).

Settings to monitor during shift

  • Beam energy: 8.5 GeV. Raster 2x2
  • Beam current:
    • The nominal beam current is 40 muA. Please adjust the actual beam current to give the single SHMS rates below 500 kHz each time you change targets. You can see this number under "Ptrig1" on the upper left side of the scaler GUI. You can go as high as 55 muA for LD2 and LH2 if the rates are low enough. The dummy target is limited to 40 muA. Approximate beam currents (good starting point) are in the tables below.
  • Trigger:
    • Main trigger is 3/4 Hodo in HMS in coincidence with 3/4 Hodo in SHMS (same as for CT experiment).
    • We will also trigger on HMS singles with a pre-scale factor. We will also have some EDT triggers.
  • Prescale: PS6 0 all the time. Set PS4 prescale to 10.

Settings to change according to run plan

  • In the 2 days of 4-pass running, we will collect data for the kinematic settings listed below. . The spectrometer settings that have to be changed for each kinematic group are highlighted below in royal blue.
    • For beam currents of 40 muA or higher, the goal is to collect about 40 mC of charge for each of LH2 and LD2, using two runs lasting about 10 minutes each if the beam is stable.
    • It is acceptable to be within 25% of the goal.
    • For the lower current runs, the goal is 40 mC times square root of (the current used divided by 40 muA). So for 10 muA, the goal is 20 mC.
    • The dummy run goal is 20 mC, which normally is about 10 minutes.

Kinematic Settings

 #  means setting number
 Ptrig6 is the approximate anticipated coincidence rate divided by 3 in Hz
 approximate current  current is the current for which rates are calculated (on LH2). It is fine to run at higher currents (preferably around 60 uA), except of course on the dummy target (40 uA).

Kinematic Group 4P1

Rad. corr. measurements for Groups 1-4 (x=0.31, Q2=3.10 GeV2)

Beam energy 8.5 GeV

HMS settings: p=-5.27 GeV, theta = 13.5

SHMS polarity: positive at first, then negative

                        PTrig6   approximate       Goals and actual mC
   SHMS  SHMS             LH2   beam current     LH2        LD2         Dummy       Done? 
 #     P Thet    z    pt Hz/3  LH2   LD2  Dum  goal got   goal  got    goal  got
 1  2.53 20.0 0.78 -0.00  364. 60.0 60.0 40.0  50.   0.   50.   0.    25.   0.
 2  2.53 26.0 0.78  0.26   60. 60.0 60.0 40.0  50.   0.   50.   0.    25.   0.
 3  1.96 30.0 0.61  0.34   98. 60.0 60.0 40.0  50.   0.   50.   0.    25.   0.
 4  1.96 20.0 0.61 -0.00  895. 60.0 35.5 40.0  50.   0.   38.   0.    25.   0.
 5 -2.53 20.0 0.78 -0.00  364. 60.0 60.0 40.0  50.   0.   50.   0.    25.   0.
 6 -2.53 26.0 0.78  0.26   60. 60.0 60.0 40.0  50.   0.   50.   0.    25.   0.
 7 -1.96 30.0 0.61  0.34   98. 60.0 60.0 40.0  50.   0.   50.   0.    25.   0.
 8 -1.96 20.0 0.61 -0.00  895. 53.9 35.1 40.0  47.   0.   38.   0.    25.   0.

Kinematic Group 4P1I

Rad. corr. measurements for Groups 5-8 (x=0.3, Q2=4.10 GeV2)

Beam energy 8.5 GeV

HMS settings: p=-3.32 GeV, theta = 19.7

SHMS polarity: positive at first, then negative

                        PTrig6   approximate       Goals and actual mC
   SHMS  SHMS             LH2   beam current     LH2        LD2         Dummy       Done? 
 #     P Thet    z    pt Hz/3  LH2   LD2  Dum  goal got   goal  got    goal  got
 1  3.40 12.0 0.66  0.01  177. 60.0 33.8 40.0  50.   0.   38.   0.    25.   0.
 2  3.40 18.0 0.66  0.37   19. 60.0 60.0 40.0  50.   0.   50.   0.    25.   0.
 3  2.65 22.0 0.51  0.47   19. 60.0 60.0 40.0  50.   0.   50.   0.    25.   0.
 4  2.65 12.0 0.51  0.01  110. 24.3 12.2 40.0  32.   0.   23.   0.    25.   0.
 5 -3.40 12.0 0.66  0.01  177. 60.0 30.0 40.0  50.   0.   35.   0.    25.   0.
 6 -3.40 18.0 0.66  0.37   19. 60.0 60.0 40.0  50.   0.   50.   0.    25.   0.
 7 -2.65 22.0 0.51  0.47   19. 60.0 60.0 40.0  50.   0.   50.   0.    25.   0.
 8 -2.65 12.0 0.51  0.01  110. 23.5 11.7 40.0  31.   0.   22.   0.    25.   0.   $

Kinematic Group 4P1II

Rad. corr. measurements for Groups 13-16 (x=0.45, Q2=4.5 GeV2)

Beam energy 8.5 GeV

HMS settings: p=-5.27 GeV, theta = 16.3

SHMS polarity: positive at first, then negative

                        PTrig6   approximate       Goals and actual mC
   SHMS  SHMS             LH2   beam current     LH2        LD2         Dummy       Done? 
 #     P Thet    z    pt Hz/3  LH2   LD2  Dum  goal got   goal  got    goal  got
 1  2.58 22.0 0.80 -0.06   38. 60.0 60.0 40.0  50.   0.   50.   0.    25.   0.
 2  2.58 28.0 0.80  0.21    8. 60.0 60.0 40.0  50.   0.   50.   0.    25.   0.
 3  2.01 32.0 0.62  0.31   14. 60.0 60.0 40.0  50.   0.   50.   0.    25.   0.
 4  2.01 22.0 0.62 -0.04  148. 60.0 60.0 40.0  50.   0.   50.   0.    25.   0.
 5 -2.58 22.0 0.80 -0.06   38. 60.0 60.0 40.0  50.   0.   50.   0.    25.   0.
 6 -2.58 28.0 0.80  0.21    8. 60.0 60.0 40.0  50.   0.   50.   0.    25.   0.
 7 -2.01 32.0 0.62  0.31   14. 60.0 60.0 40.0  50.   0.   50.   0.    25.   0.
 8 -2.01 22.0 0.62 -0.04  148. 60.0 60.0 40.0  50.   0.   50.   0.    25.   0.