Data provided by Todd Satogata, March 31, 2016 Note from Todd: --------------- My advice would be to keep the quad "on loop" when performing your studies, and structure your study to scan from high current to low current which is the direction where the quad is "on hysteresis" according to the control system maps. If you scan from low current to high current (or negative to positive), you will end up suffering a hysteresis cycle with every new setting to stay on hysteresis! the bottom line: ---------------- These map values should only be taken as valid if the magnet current is first raised to near +20A and then continuously lowered to the operating point. If it needs to be raised, first cycle back to +20A and then decrease the current to the desired setpoint. To convert these numbers to B*L, use the following formulas where G is the appropriate value interpolated from the first table below. BxL = L * y * G ByL = L * x * G where (x,y) is the offset ofthe beam from the neutral axis of the magnet, and |L|=30cm. The overall sign of the L in this formula is not known (depends on how the leads were connected to the power supply) and will be determined empirically during commissioning. MQPAD00 ======= ======== Current Gradient [A] [G/cm] ======= ======== -19.000 -2787.980 -18.000 -2649.007 -16.000 -2363.083 -14.000 -2071.247 -12.000 -1775.807 -10.000 -1478.073 -8.000 -1178.753 -6.000 -878.197 -4.000 -576.650 -2.000 -273.957 -0.199 1.117 0.000 30.040 2.000 333.907 4.000 636.527 6.000 938.557 8.000 1239.747 10.000 1539.363 12.000 1836.540 14.000 2129.883 16.000 2415.357 18.000 2678.310 19.000 2788.197 ======= ======== ======= ======== Current Residual nonlinear Gradient [A] [G/cm] ======= ======== -19.000 17.874 -18.000 7.734 -16.000 -4.569 -14.000 -10.959 -12.000 -13.746 -10.000 -14.239 -8.000 -13.146 -6.000 -10.816 -4.000 -7.496 -2.000 -3.029 -0.199 3.491 0.000 2.741 2.000 8.381 4.000 12.774 6.000 16.578 8.000 19.541 10.000 20.931 12.000 19.881 14.000 14.998 16.000 2.244 18.000 -33.029 19.000 -72.256 ======= ========