Thermal stability analysis of the niobium made elliptical cavity for superconducting electron linac project

Design and development of injector cryomodule (ICM) for the superconducting electron linac (elinac) is going on at VECC. Injector cryomodule is meant to house one nine-cell niobium elliptical SRF cavity operating at 2K. Thermal stability analysis has been carried out to evaluate the effect of the cavity thickness, the residual resistivity ratio (RRR) of the cavity material and the dimension of the impurities present in the cavity surface, on the performance of the cavity. Based on this analysis we have been able to formulate the inspection procedure for the niobium sheet material and the cleaning techniques. The surface impurities size must be kept below the prescribed value to prevent thermal break down of the cavity. (author)