Measurement of ac losses in superconductors due to ac transport currents in applied ac magnetic fields

A new technique for the measurement of ac losses in superconductors due to applied magnetic fields and transport currents is reported. This technique is derived from consideration of the source of the energy losses, rather than by the imposition of any model for magnetic field distribution within the superconductor and allows us to present new data on the losses in BSCCO-2223 multi-filamentary conductor due to ac fields and dc currents, or due to ac fields and ac currents. Based on these measurements we provide guidelines for estimating the losses in BSCCO-2223 conductors.