Energy losses in mixed matrix superconducting wires under fast pulsed conditions

Energy losses have been measured on a set of mixed matrix (CuNi, Cu, NbTi) superconducting wires at \´s up to 1.5 × 10⁷G/s. The losses have been measured as a function of wire diameter, twist pitch, maximum applied field, and . Both static and dynamic losses were measured for a field applied perpendicularly to the wire axis. The dynamic losses were measured by slowly applying an external field to a sample and then causing the field to decay exponentially in roughly 1 ms to 10 ms. Under low B (9 kG) and (10⁶G/s) conditions the hysteretic loss dominated. At high B (21 kG) and (1.5 × 10⁷G/s) the matrix losses became dominant. The systematic variation of the losses with the mentioned parameters will be presented and will be compared to theoretical predictions.