Parity Checks

In the process of editing and updating this page. Please contact Juliette Mammei crowder@jlab.org with questions or suggestions.

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Shift Checklist Instructions

IF THERE IS A DISCREPANCY AND VALUES DON'T MATCH TABLE BELOW, CALL EXPERT!

Check whether the IHWP is IN or OUT and record its state. Check whether the Wien Flip State Settings is FLIP RIGHT or FLIP LEFT and record its state. For the rest of the variables, consult the table below (for IHWP OUT consult values on left column, for IHWP IN consult values on right column) and verify the the present settings are consistent with the table and record them and check the checkmark on the check list IF and ONLY IF the values match those in the table. Otherwise there is a problem.

For detailed instructions on how to check each parity variable, see below.

Table 1 - List of the correct settings for Insertable Half Wave Plate (IHWP) IN and OUT / Wien Flip RIGHT and LEFT.

Variable	IHWPout	IHWPout	IHWPin	IHWPin
Flip State	FLIP-RIGHT	FLIP-LEFT	FLIP-RIGHT	FLIP-LEFT
RHWP	1500	1500	1500	1500
VWien Angle	+88°	-90.6°	+88°	-90.6°
Solenoid Angle	89.956°	88.028°	89.956°	88.028°
HWien Angle	-29.64 °	-29.64 °	-29.64 °	-29.64 °
PC ON/OFF	ON	ON	ON	ON
V PITA	-330 ± 300 counts	-330 ± 300 counts	-100 ± 300 counts	-100 ± 300 counts
V L/4	12670	12670	12670	12670
V aposU	1146	1146	913	913
V aposV	-1000	-1000	-1003	-1003
V dposV	0	0	0	0
V dposU	0	0	0	0
HallA IA	37100	37100	28852	28852
HallB IA	33779	33779	32275	32275
HallC IA	19000± 10000 counts	19000± 10000 counts	47822± 10000 counts	47822± 10000 counts

Record of Parity Settings

Figure 1 - Main JMenu window.

Figure 2 - PGUN Main window in JMenu.

Figure 3 - Spin Controls window.

Figure 4 - RTP cell window.

Figure 5 - Parity Controls window.

In general, you can try to search for things in JMenu (next to the magnifying glass, where compton is written in Figure 1) to see if they will come up. The instructions below tell you one way to navigate through the menus to get to the desired screen (there may be other ways to get there).

List

• Insertable half-wave plate (IHWP) Setting (IN or OUT)
  • From JMenu, in the search frame, type "Parity" (see Figure 5)
  • In the dropdown menu, choose "Parity Controls"
  • The setting is indicated by the depressed button in the top orange box called INSERTABLE waveplate
    • See Figure 5, top orange box, it is OUT in this figure
  • Another way to check: in JMenu, mouse over "Injector" (see Figure 1)
  • In the dropdown menu, choose "GUN/Laser"
  • From there, choose "PGUN Main"
  • The setting is indicated by the depressed button (see Figure 2, very bottom left corner, it is OUT in this figure)
• Rotatable half-wave plate (RHWP) setting (value like 1532)
  • Right below the INSERTABLE waveplate box (see Figure 5) in the yellow box labelled ROTATING waveplate is the set value (1532 in Figure 5)
  • Another way to check: Right next to the IHWP box in the PGUN window is the set value of the RHWP (1532 in Figure 1)
  • The value is usually 1 these days, after the power outage wiped the 1532 number

• Wien settings (FLIP RIGHT or LEFT, or LONG)
  • From JMenu, mouse over "Injector"
  • In the dropdown menu, choose "Spin", then "Spin Controls"
  • The FLIP LEFT or RIGHT or Longitudinal (see Figure 3, very top - middle region, it is "Longitudinal" in this figure)
• Vertical Wien Angle (degrees)
  • The variable is "VWienAngle"
  • Find it at the bottom of the left box of the spin controls window
  • The value is -0.00 in Figure 3
• Solenoid angle (degrees)
  • The variable is "Phi_FG"
  • Find it at the bottom of the middle box of the spin controls window
  • The value is 86.901 in Figure 3
• Horizontal Wien Angle (degrees)
  • The variable is HWienAngle
  • Find it at the bottom of the right box of the spin controls window
  • The value is -0.00 in Figure 3

• RTP settings
  • From JMenu, in search frame, type "RTP"
  • In the dropdown menu, choose "RTP cell"
  • See Figure 4 for example.
  • The ON/OFF button is in the pink region on the top right
• Main RTP Cell ON/OFF
  • This should always be ON
  • The voltage values are in the light purple region on the right
• VL/4 (counts)
  • The variable is in Figure 4
  • The value is always 12670 as in Figure 4.
  • It should always be the case that VL/4=VL/41=VL/42
• VPITA (counts)
  • The variable is 371 in Figure 4
  • The value should be fluctuating by a few hundred counts
  • It should always be the case that "VPITA"="VPITA,1"="VPITA,2"
• VaPos,U(counts)
  • The variable is 1509 in Figure 4
• VaPos,V(counts)
  • The variable is 337 in Figure 4
• VdPos,U(counts)
  • The variable should always be 0 and is 0 in Figure 4.
• VdPos,V(counts)
  • The variable should always be 0 and is 0 in Figure 4.

• IA settings
  • From JMenu, in the search frame, type "Parity"
  • In the dropdown menu, choose "Parity Controls"
  • The IA settings for the 3 halls are in the bottom half of the screen in the tan, grey, and light purple sections
• HALL A:IA
  • The Variable is 42570 in Fig. 5
  • It is located in the bottom left tan region in the blue boxes next to "COUNTS READ" under DAC03
  • DAC03, DAC04,DAC05,DAC06 should all read identical values
• HALL B:IA
  • The Variable is 37286 in Fig. 5
  • It is located in the bottom center grey region in the blue boxes next to "COUNTS READ" under DAC07
  • DAC07, DAC08,DAC09,DAC10 should all read identical values
• HALL C:IA
  • The Variable is 25881 in Fig. 5
  • It is located in the bottom right light purple region in the blue boxes next to "COUNTS READ" under DAC11
  • DAC11, DAC12,DAC13,DAC14 should all read identical values and should be fluctuating

• 'Parity Aq feedback'
  • Parity feedback HOW-TO

• 'Flipping IHWP state'
  • Flipper

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