How to set HRS magnets

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For APEX, regulators for Q1, Q2, Q3 are always OFF and only used for the dipole. Q1, Q2, Q3 magnets will be set by current.

Use a procedure similar to the Q2 and Q3 to cycle the Q1s when starting from off condition:

1. Check regulator OFF for Q1, Q2 and Q3. Leave the dipole regulator ON
2. Set the momentum of the spectrometer you want. The dipole should start moving towards that setting. The NMR will be set too. Q1, Q2 and Q3 will not change.
3. Turn on the Q1 power supply if not on already (The polarity of the right Q1 needs to be set with the supply off)
4. Run the Q1 power supply to 900 A.  Let it stay there for about five minutes
5. Set the desired current for the left/right Q1. The Hall probes should read positive for positive particles and negative for negative particles (WITH CURRENT IN THE MAGNETS)
6. Procedure for Q2 and Q3 is similar but with different values to cycle the magnets: 1600A for LQ2, LQ3, and 1400 A for RQ2, RQ3.

  • If one can not reset the magnet remotely:
Do NOT go into the hall to reset by yourself. Contact magnet expert/tech on-call.
  • Base current for quads:

One needs to scale the set current according to the momentum.

Left Arm:

Q1: 138.93 Amp/GeV     (1.5 GeV - 208.39 Amps)
Q2: 408.60 Amp/GeV     (1.5 GeV - 612.89 Amps)
Q3: 480.25 Amp/GeV     (1.5 GeV - 720.37 Amps)    

Right Arm:

Q1: 133.42 Amp/GeV     (1.5 GeV - 200.13 Amps)
Q2: 408.38 Amp/GeV     (1.5 GeV - 612.56 Amps)
Q3: 480.00 Amp/GeV     (1.5 GeV - 720.00 Amps)