Dissipated power measurements in the A0 SRF cavity system

Fermilab operates a single TESLA 9-cell superconducting RF cavity in support of a photoelectron R and D beam line. Power going into the 1.8K cryogenic system via static heat leak and RF dissipation is measured from the rate of rise of the pressure in the helium bath. This paper describes the techniques used to determine the cryostat heat load and the RF performance of the cavity. A photo-injector has been constructed at Fermilab to produce a low-energy (14--18 MeV) electron beam with high charge per bunch (8 nC), short bunch length (1 mm RMS), and small transverse emittance (<20 mm mrad). The facility was used to commission a photo-cathode RF gun for the TESLA Test Facility (TTF) Linac at DESY. At present, the Fermilab machine is being used for R and D in bunch length compression and fast beam diagnostics; experiments in plasma wake field acceleration and channeling acceleration are in preparation