Cable design and related issues in a fast-cycling superconducting magnets

Hollow superconducting cables for a fast-cycling synchrotrons are discussed. The essential features of the cable designed for the Nuclotron at JINR are presented. New versions of a hollow NbTi superconducting cable are described. The first test results with a cable that has been designed for an operating current of 12 kA at B = 2 T, dB/dt = 4 T/s and pulse repetition rate f = 1 Hz are presented. Further possibilities of using hollow cables both for dipoles with bore field of 4-6 T operating at repetition rate of 0.5 Hz and low field (B = 1-1.5 T) magnets operating at f = 10-20 Hz are discussed. (author)