arXiv subjects
Publications and source records attributed to V. Tupikov.
Powered operation of Cryomodule 1 (CM-1) at the Fermilab SRF Beam Test Facility began in late 2010. Since then a series of tests first on the eight individual cavities and then the full cryomodule have been performed. We report on the results of these tests and lessons learned which will have an impact on future module testing at Fermilab.
A LLRF control and data acquisition system for the 8-cavity cryomodule1 at the ILCTA has been implemented using three 33-channel ADC boards in a VXI mainframe. One card each is dedicated to the cavity probes for vector control, forward power and reverse power measurements. The system is scalable to 24 cavities or more with the commissioning of cryomodules 2 and 3 without additional hardware. The signal processing and vector control of the cavities is implemented in an FPGA and a high speed data acquisition system with up to 100 channels which stores data in external SDRAM memory. The system supports both pulsed and CW modes with a pulse rate of 5 Hz. Acquired data is transferred between pulses to auxiliary systems such as the piezo controller through the VXI slot0 controller. The performance of the vector control system is evaluated and the design of the system is described.
In the recently commissioned superconducting RF cavity test facility at Fermilab (SCTF), a 325 MHz, β=0.22 superconducting single-spoke resonator (SSR1) has been tested for the first time with its input power coupler. Previously, this cavity had been tested CW with a low power, high Qext test coupler; first as a bare cavity in the Fermilab Vertical Test Stand and then fully dressed in the SCTF. For the tests described here, the design input coupler with Qext ~ 106 was used. Pulsed power was provided by a Toshiba E3740A 2.5 MW klystron.