KQ1-KQ2

The mechanical designs of the two quadrupole magnets, Q1 and Q2 are shown in figures and . The Q1 and Q2 were designed so that their upper and lower yokes are separated to allow photons and deflected electron beams escape the gap of the quadrupole magnets. They are to be mechanically supported by spacers between the upper and lower poles and the widths of Q1 and Q2 are minimized as shown in the figures. By this way, the Q1 can be installed very close to the Splitter magnetwithout interference to the HES spectrometer and the larger solid angle of the HKS is realized.

Parameters for the Q1 and Q2 magnets are summarized in table.

   
                                   Q1                           Q2
Bore radius (mm)                  120                           145
Pole length (mm)                  840                           600
Max. Ampere turns (A turns)       224000                       144000
Number of turns                   256                           320
Conductor size                   8 X 8 (phi 6 hole)          13.5 X 11.5 (phi 6.3 hole)
Coil Winding                     Double Pancake Winding        Solenoid Winding
Field Gradient (T/m)             6.6                            4.2
Max. Current (A)                  875                           450
Resistance  (m$\Omega$)           181 (@55 C)                   119 (@45 C)
Cooling Water Flow rate (l/m)     49.6                          17.3
Pressure drop (MPa)               0.36                          0.38
Number of Coolant circuits         16                            8
Total Magnet Weight (ton)          8.2                          10.5