TESLA test cell cryostat support post thermal and structural analysis

TeV Superconducting Linear Accelerator (TESLA) cryostats consist of eight, 1-meter-long radio frequency (RF) cavity modules cryogenically connected in series with one focusing quadrupole. Each module contains one, 9-cell superconducting RF cavity operating at 1.3 GHz in a 1.8K helium bath. Individual modules are self-contained in the that they have their own input couplers, high order mode couplers, and tuning mechanisms. Services common to the entire cryostat consist of 70K and 4.5K thermal radiation shields, shield supply and return lines, a 1.8K helium supply line, and a gas helium return pipe. All cavity modules, the quadrupole, and cryogenic seances are contained in a single 12-meter-long vacuum vessel. The goal of the present work on TESLA is the successful fabrication and test of four complete cryostat assemblies. These cryostats will be installed in a string cooled to operating temperature, and powered. This test will address problems which may arise when modules are installed in a tunnel environment It will also permit testing of the basic cooling concepts, measurement of static heat losses, and measurement of the RF performance of all cavities