Progress of 2-Cell Cavity Fabrication for Cornell ERL Injector

Five 1300 MHz superconducting niobium cavities are to be used for the injector of Cornell ERL prototype. The beam power requirement (100 kW each cavity CW) and the need to minimize emittance dilution due to the cavity structure have important impacts to the design and fabrication of these cavities. We plan to use Conflat stainless-steel flanges brazed to niobium tubes. Two copper prototype cavities have been built and measured. Parts for the first niobium cavity have been manufactured. In this report, we will present the progress of the prototyping copper as well as niobium cavities.