The decommissioning of the Tevatron represented the end of an era, but it also is ushering in the next generation of physics by providing valuable equipment to other experiments.
"We don't have enough funding to buy things new, so when we want to improve our experiments, we must search for and reuse equipment," said Bogdan Wojtsekhowski, a staff scientist at Jefferson Lab. "Scientists share equipment all the time. It's the best way to get more physics for your budget."
Fermilab’s CDF experiment is donating photomultiplier tubes, computers, electronics racks and other equipment to experiments located all over the world, said Jonathan Lewis of Fermilab’s Particle Physics Division, who is organizing the decommissioning of the detector.
“These computers are going to a lab in Korea,” Lewis said during a tour of the building. “And we’re sending those electronics racks to Italy.”
Jefferson Lab received more than 600 of the Tevatron experiment's photomultiplier tubes for an experiment measuring the charge distribution inside protons. New, these photomultiplier tubes would have cost $700,000, but because they came from Fermilab, J-Lab had to pay only roughly $1,000 for disassembly and shipping costs.
“We could not have afforded these photomultiplier tubes new, so we are very appreciative that we could get them from Fermilab,” Wojtsekhowski said. “They will significantly enhance this experiment’s detection capabilities – by 30 percent, which means we will get more accurate data for the same beam time and stay within our budget. It was amazing luck.”
The equipment swap is not limited to just national labs. Many universities, which often have tight research budgets, have placed claims on old Tevatron material.
“When an experiment shuts down, people know about it,” said Carnegie Mellon professor James Russ. “I worked on CDF, so I knew what equipment would become available.”
Russ also received CDF photomultiplier tubes, which he is using to improve the detection system of an experiment studying secondary particle showers generated by tau neutrinos.
“Our research uses the same principles as CDF, except we’re looking for particles produced by high-energy cosmic rays instead of by a proton beam,” Russ said.
While most of the equipment that CDF is giving away is still highly functioning, even the old and broken parts have found homes.
Professor Yasar Onel from the University of Iowa has a use for these seasoned bits. He is designing a calorimeter that can detect secondary emissions from particle collisions in high-radiation environments.
“Before we can get funding, we need to have a prototype,” Onel said. “Buying components from outside sources is expensive, so we rely on old equipment to prove our ideas.”
Onel is building his prototype using old CDF photomultiplier tubes.
Now that the Tevatron’s old equipment has been reassigned and shipped to new projects, engineers are preparing to give CDF a makeover of its own. The first phase of the renovations is securing the detector and removing potentially dangerous equipment, such as flammable gas and cryogens.
“Once the building is safe, there are various purposes it could serve,” Lewis said.
Currently the CDF decommissioning team is preparing to turn the site into an educational display for tour groups.
“We will have interactive displays in the counting room and control room,” Lewis said. “The visitors would then go down to see the CDF detector and elements of the apparatus such as a spare calorimeter segment and the drift chamber from [the Tevatron’s first run].”
But impending plans for the Illinois Accelerator Research Center and a proposed experiment called ORKA, designed to observe rare kaon decays, might supersede these educational endeavors and repurpose CDF as a research facility.
“The CDF assembly hall might eventually become lab space for IARC,” Lewis said. “And if ORKA gets approved, it will use the CDF magnet in the collision hall and a beamline in the Tevatron tunnel.”
Construction of the IARC Office, Technical and Education building adjacent to the CDF hall will begin in April, and the scientific goals for ORKA were approved last December. These developments could take the remaining parts of the CDF detector out of museum mode and put them back at the cutting-edge of particle physics research.