The eddy current distribution in a thin superconducting strip subjected to an ac field perpendicular to its surface is derived for a critical-state model with constant critical current. From this, an approximate expression is obtained for the hysteretic loss per cycle. An approximate expression is also given for a field-dependent critical current.

A method of imaging short T2 materials is demonstrated that makes use of a large sinusoidally time-varying magnetic field gradient. The technique is experimentally verified by imaging both rubber and PTFE samples. A multiple pulse scheme is also described that is shown to provide a signal-to-noise improvement with no time penalty.

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