Spin flip/quarter wave plate calibration

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This page summarize the calibration data for quarter wave plate holders, which control the pumping laser polarization of Hall A He3 Polarized Target.

Connection Map

Pumping Direction Laser Component Motor ID Laser Platform Patch Panel 50Ft Ext. Cable ID Controller ID
Longitudinal S Wave 1 (tested & taken out) 1 1 None
Longitudinal P Wave 2 (tested & taken out) 2 2 None
Transverse S Wave 3 3 3 0338
Transverse P Wave 4 4 4 1474
Vertical S Wave 5 5 5 1426
Vertical P Wave 6 6 6 1423

Current Setting

Log

  1. Summer 2008, Init calibration
  2. Dec 02, 2008, Transverse Laser Absorption Calibration
    • Try to rotate motor # 0338 and # 1474 to maximize absorption spectrum @ 795.1nm
    • Condition: Transvers -; Spin -; 3x Comet Laser
    • Result : Get maximize absorption peak @ 0338 = 3 (Degree, readback); 1474=-84 (Degree, readback)
  3. May 22, 2009; Recalibrate Motor #3 and #4 in lab. Their calibration angle kept unchanged. However, Auto calibration Error of motor #3 shifted from -1.5 to 0.2

Setting Table

Motor ID Controller ID Description Alignment Angle/Degree Auto calibration Error/Degree Spin Up Read Back/Degree Spin Down Read Back/Degree
1 N/A Not In Use 8.4 0.15 8.25 -81.75
2 N/A Not In Use 8.5 0.40 8.10 -81.90
3 0338 Transverse S Wave 7.5 0.2 7.3 -82.70
4 1474 Transverse P Wave 8.8 0.00 8.80 -81.20
5 1426 Vertical S Wave 10.8 0.40 10.40 -79.60
6 1423 Vertical P Wave 9.8 1.00 8.80 -81.20

  • Motor ID : The sticker attached to the motor
  • Controller ID : ID number of control connected to the motor
  • Alignment Angle : When the mark of Q-wave plate is at this angle, all plates will convert a vertical polarized laser to a circular polarized one. Besides, the polarization direction is the same.
  • Auto calibration error : is the marker angle on the plate holder, while the holder is shown to be rotated to 0 degree on the computer. The reason why it is not 0, is due to non-perfect precision of automatic calibration.
  • Position Up/Down Read Back: The angle setting on the computer for spin state Up/Down.

Old Settings

Before May 22,2009

Motor ID Controller ID Description Alignment Angle/Degree Auto calibration Error/Degree Spin Up Read Back/Degree Spin Down Read Back/Degree
1 N/A Not In Use 8.4 0.15 8.25 -81.75
2 N/A Not In Use 8.5 0.40 8.10 -81.90
3 0338 Transverse S Wave 7.5 -1.50 6.5 (Dec 02, 2008 re-calib) -83.5 (Dec 02, 2008 re-calib)
4 1474 Transverse P Wave 8.8 0.00 6.5 (Dec 02, 2008 re-calib) -83.5 (Dec 02, 2008 re-calib)
5 1426 Vertical S Wave 10.8 0.40 10.40 -79.60
6 1423 Vertical P Wave 9.8 1.00 8.80 -81.20

  • Motor ID : The sticker attached to the motor
  • Controller ID : ID number of control connected to the motor
  • Alignment Angle : When the mark of Q-wave plate is at this angle, all plates will convert a vertical polarized laser to a circular polarized one. Besides, the polarization direction is the same.
  • Auto calibration error : is the marker angle on the plate holder, while the holder is shown to be rotated to 0 degree on the computer. The reason why it is not 0, is due to non-perfect precision of automatic calibration.
  • Position Up/Down Read Back: The angle setting on the computer for spin state Up/Down.

Before Dec 2, 2008

Motor ID Controller ID Description Alignment Angle/Degree Auto calibration Error/Degree Spin Up Read Back/Degree Spin Down Read Back/Degree
1 N/A Not In Use 8.4 0.15 8.25 -81.75
2 N/A Not In Use 8.5 0.40 8.10 -81.90
3 0338 Transverse S Wave 7.5 -1.50 9.00 -81.00
4 1474 Transverse P Wave 8.8 0.00 8.80 -81.20
5 1426 Vertical S Wave 10.8 0.40 10.40 -79.60
6 1423 Vertical P Wave 9.8 1.00 8.80 -81.20

  • Motor ID : The sticker attached to the motor
  • Controller ID : ID number of control connected to the motor
  • Alignment Angle : When the mark of Q-wave plate is at this angle, all plates will convert a vertical polarized laser to a circular polarized one. Besides, the polarization direction is the same.
  • Auto calibration error : is the marker angle on the plate holder, while the holder is shown to be rotated to 0 degree on the computer. The reason why it is not 0, is due to non-perfect precision of automatic calibration.
  • Position Up/Down Read Back: The angle setting on the computer for spin state Up/Down.


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