Experimental studies on stabilities of Rutherford cables for superconducting accelerator magnets

The stability of a multi-stranded superconducting cable which is used for superconducting accelerators magnets is strongly influenced by the uniformity of steady-state current distribution among strands and smooth transient current sharing among the strands. The controlling factor is the interstrand crossover resistance. A large interstrand crossover resistance will cause non-uniform current distributions and uneven current sharing. In order to investigate stabilities of two kinds of Rutherford cables with different matrix structures and different crossover resistances, we have measured minimum quench energies with the aid of a heater and observed current sharing phenomena. The experimental results were interpreted in terms of interstrand crossover resistance.