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UMER 73 deg. Matching Settings 2006-08

The table below lists the updated magnet currents for best matching for the most commonly-used beams, for a target sigma_0 of 73 degrees. The calculations use the new hard-edge model, assume new quads throughout the ring, and include bends. See Notes below for some additional information.
  0.6 mA / 5.5 mm emit 5.8 mA / 16 mm emit 23.5 mA / 20 mm emit 100 mA / 60 mm emit
Magnet Position Peak Field [G] Current Peak Field [G] Current Peak Field [G] Current Peak Field [G] Current Magnet
  [cm] or Gradient [G/cm] [A] or Gradient [G/cm] [A] or Gradient [G/cm] [A] or Gradient [G/cm] [A]  
SOL 17.66 88.00 4.92 98.10 5.50 98.10 5.50 102.50 5.75 SOL
Q1 40.00 - - 4.57 1.27 4.57 1.27 4.57 1.27 Q1
Q2 53.50 - - 7.69 2.13 7.87 2.18 8.21 2.27 Q2
Q3 72.41 1.83 0.51 8.21 2.27 7.19 1.99 7.46 2.07 Q3
Q4 91.79 5.26 1.46 8.06 2.23 7.11 1.97 7.34 2.03 Q4
Q5 106.15 7.35 2.04 7.96 2.21 7.39 2.05 7.20 1.99 Q5
Q6 122.14 7.31 2.02 7.78 2.16 7.89 2.19 7.75 2.15 Q6
YQ 137.31 6.15 5.50 6.11 5.46 6.10 5.45 6.10 5.44 YQ
QR1 153.31 5.79 5.73 5.73 5.68 5.72 5.66 5.72 5.66 QR1
QR2 169.31 7.85 2.17 7.79 2.16 7.78 2.15 7.78 2.15 QR2

 
 
 
 
 
QR3 185.31 7.61 2.11 7.61 2.11 7.61 2.11 7.61 2.11 QR3
QR70 1257.31 7.61 2.11 7.61 2.11 7.61 2.11 7.61 2.11 QR70

 
 
 
 
 
QR71 1273.31 7.86 2.18 7.78 2.16 7.89 2.19 7.75 2.15 QR71

 
 
 
 
 
    Target State Target State Target State Target State  
a0 [mm]   1.37 2.95 5.22 10.66
b0 [mm]   1.4 3.08 5.61 11.49
ap0 [mrad] 6.42 13 22.31 45.41
bp0 [mrad] 6.54 13.63 24.22 49.52
Created by ramiak
Last modified 2006-11-13 09:20 PM

Notes

Posted by ramiak at 2006-08-24 03:30 PM
The new quadrupoles did make quite some difference in the matching solution. Including the bends did not change the solution much apart from requiring QR1 be slightly stronger. However if that effect is ignored, there will be a mismatch, so I included the bends in all these calculations. Varying the beam current makes little difference in the Y-magnets, which is good, but affects the injector settings. So far, the biggest difference comes from the solenoid. Previously I had guessed a position of 17.5 cm. Here I now use 17.66 cm, Santiago's latest value, and this 1.6 mm displacement results in huge differences for the currents of Q2-Q6. This alerts us to the importance of careful measurements of the injector magnet positions!

Finally, These calculations aim at a sigma_0 of about 73 degrees in the ring. This is so as to keep some consistency with previous experiments. At some point we need to adjust our settings so as to achieve 76 degrees - which is the design value.

Target State

Posted by ramiak at 2006-11-13 09:45 PM
Target state in this case is defined in the midplane of the bending dipoles. This is NOT what you expect to see on the screen.

UMER 2005
Support for the UMER project is being provided by the U. S. Department of Energy.