Influence of a restricted normal zone on the limiting current of a superconducting cable and field distribution in the aperture of a dipole magnet

The values of limiting current in transverse magnetic fields of 0.5-5.3 T have been measured for samples of a superconducting (SC) cable with a specially created restricted normal zone (RNZ) in the form of copper insertions. Harmonic amplitudes of the magnetic field in the SC-dipole aperture have been calculated in the two-dimensional approximation for similar RNZs producing the redistribution of current density in the cable section. The behaviour of the harmonic amplitudes are in qualitative agreement with the results of measurements performed previously under subcritical pulsed heating as a function of the depth of penetration into RNZ in the SC cable