Parameterization of hysteresis effects in accumulator quadrupole magnets

The hysteresis curves of two Accumulator sample magnets have been measured, one large quadrupole and one small quadrupole. Based upon these measurements, a parameterization of hysteresis effects is deduced and generalized to other magnets. The goal is to incorporate the best knowledge of the magnets we have into the Accumulator model, on which lattice measurements are based and which is used to calculate an accurate first guess at the E-835 deceleration tables. Since a well-defined sequence of current cycles is performed during Accumulator operations, some simplifying hypotheses can be applied