Cryomodule Test Facility will help advance SRF technology

Construction of Fermilab’s Cryomodule Test Facility (left) is scheduled for completion later this year. The facility will house radiofrequency systems and a cryogenic plant, crucial components for testing superconducting radio-frequency cavities for the SRF accelerator test facility at the New Muon Lab (right). Photo: Jerry Leibfritz

A new building will help keep Fermilab’s next generation of accelerators stay cool. Real cool.

Engineers are getting ready for an upgrade to the cryogenic system for the superconducting radio-frequency accelerator at the New Muon Lab.

Fermilab’s Cryomodule Test Facility (CMTF) will house a new cryogenic plant, which will play an essential supporting role in the laboratory’s future SRF research projects.

Construction of the building for this facility, which began in August 2010, will come to an end this fall. Fermilab engineers look forward to installing an energy-efficient superfluid helium cryogenic system in spring 2013.

CMTF will also include radio-frequency power systems and two cryomodule test stands. The test stands, will be used to assess cryomodule performance prior to their commissioning. They are being designed in collaboration with engineers in India.

“We’ll use the test stands to first send radiofrequency power to the individual SRF cavities and then to all the cavities at once,” said Jerry Leibfritz, project leader of the SRF test facility. “We need to make sure that the entire cryomodule functions properly and produces the specified accelerating gradient before it can be installed in an accelerator.”

The Cryomodule Test Facility provides space for testing cryomodules to verify that the individual cavities work together to produce a high accelerating gradient. Engineers will test the cryomodules prior to installing them into linear accelerators. Photo: Jerry Leibfritz

Linear accelerators, such as the proposed Project X and ILC, are composed of a string of cryomodules, which require cryogenic liquids to cool them to 2 Kelvin. A cryosystem built from spare Tevatron components is currently used to cool the SRF accelerator at NML, which currently consists of one operational cryomodule without beam.

Although the repurposed cooling system is sufficient for now, engineers are planning on installing several additional cryomodules into the SRF accelerator and generating beam in the near future. These efforts will require a higher-capacity cryogenic system to provide adequate cooling, Leibfritz said.

“We bought a big cryogenic refrigerator for the cryoplant and we’ll get many of the other components from the Tevatron after it’s decommissioned,” Leibfritz said.

Contractors are now putting the final touches on the building, including painting, electrical work and installing the crane that will be used to position the CMTF refrigerator in place. Funding for CMTF construction is provided by the American Recovery and Reinvestment Act.

“Now that construction is winding down, the excitement at NML will focus on getting the SRF accelerator ready to generate beam,” Leibfritz said. “CMTF will play a crucial role in making that possible.”

— Christine Herman