Preliminary study of an integral harmonic analysis magnetic field measurement system for long SSC magnets

We described the research and development required to design and build a prototype system capable of making integrated magnetic multipole measurements of warm and cryogenic 50 mm bore SSC dipole and quadrupole magnets utilizing a warm probe in a warm finger. Our experience and some preliminary studies indicate that it is highly unlikely that a 16 meter long probe can be fabricated that will have a twist below several milliradians at any temperature. Consequently we describe a segmented 16 meter long probe for which we intend to calibrate the phase of each segment to within 0.1 milliradians. The data for all segments will be acquired simultaneously, and integrated data will be generated from the vector sums of the individual segments. The calibration techniques and instrumentation required to implement this system are described. The duration of an integral measurement at one current is less than ten seconds, which is three orders of magnitude shorter than that required by the mole technique presently being used. The system is based on an extrapolation of the techniques used at LBL to measure cryogenic 1 meter models of SSC magnets with a cryogenic probe. 3 refs., 3 figs