Refurbished Booster cavities in place, PIP begins 15-hertz operations

With the installation of the 17th Booster cavity, the PIP team has begun 15-hertz operations critical for the laboratory’s neutrino program. Photo: Reidar Hahn

For nearly four years, the Proton Improvement Plan team in the Accelerator Division have been refurbishing radio-frequency cavities for the Booster accelerator.

Last week the final cavity in need of refurbishment was removed from the tunnel and replaced with a refurbished one. With 17 refurbished cavities in place, the Booster is now capable of operating at the nominal beam intensity at a rate of 15 hertz, meaning that it can accelerate and deliver 15 proton batches every second, double what it was able to handle before the improvement work began. The increased rate will allow the Fermilab accelerator complex to deliver the higher proton flux required for the laboratory’s neutrino experiments.

This is a critical step for PIP, though additional cavity work and tasks remain in the plan. The next step of 15-Hz beam operations testing is already under way; the team demonstrated low-intensity 15-Hz beam operations for the first time on Monday.

The Booster is the third component in Fermilab’s accelerator chain, preceded by the RFQ and the Linac. The roughly quarter-mile-circumference ring sends proton beam into the 2-mile-around Recycler, which offloads beam into the Main Injector, Fermilab’s flagship accelerator. Beam then exits the Main Injector to myriad experiments.

Congratulations to the Proton Improvement Plan team on this important milestone.