Data for the extraction of the critical temperature of niobium films deposited on copper produced at CERN for SRF applications

Each data set contains the voltage signal amplitude induced in a pickup coil by an alternating magnetic field, crossing the niobium-film-on-copper sample during its state transition from normal conducting to superconducting, the corresponding sample temperature and the estimated errors for the two measured quantities. File columns: #1 sample temperature in Kelvin, #2 estimated temperature error, #3 voltage amplitude in pickup coil in Volt, #4 estimated amplitude error.

One data set corresponds to one sample. The critical temperature can be extracted as fit parameter by fitting the amplitude versus temperature data with a logistic function, where it corresponds to the half height of the state transition curve.