Mu2e moves forward

Fermilab Director
Nigel Lockyer

Today’s column shines a spotlight on the next major experiment proposed to be built at Fermilab: Mu2e. The recent P5 report placed Mu2e first in line for construction among major projects, to be followed immediately by the high-luminosity LHC and then by LBNF.

The Mu2e project took a big step forward two weeks ago when DOE approved the CD-3a step in the construction process. Until now, the team had been focused on the development of a detailed design for the experiment, including modifications to the Fermilab accelerator facility and a new hall to house the detector. CD-3a approval means that the team can purchase 45 miles of custom-made superconducting cables for the experiment’s solenoid magnets.

Mu2e stands for muon-to-electron conversion, which tells you exactly what the 155 scientists working on the experiment will use it to search for. The collaboration has spent five years designing a sophisticated apparatus that will be used to search for the spontaneous conversion of muons into electrons in the vicinity of an atomic nucleus. While there are many predictions for how this conversion could happen, none are included in the Standard Model of particle physics. So if the conversion is detected, it’s a clear signal for new physics.

The experiment’s complex magnet system uses four different types of superconductors that required a year of R&D to develop, including an exhaustive series of tests both at vendors and at the lab. It will take two separate vendors over a year to fabricate all of the conductor required, so the DOE’s approval of this long-lead procurement will allow the experiment to accelerate its schedule to be ready to take physics data in 2020.

Mu2e is proposed to join the Muon g-2 project on Fermilab’s new Muon Campus, making excellent use of the muon beams that our accelerator complex will provide starting later this decade.

Congratulations to Ron Ray for leading the project team through a successful CD-3a review and to the Technical Division for carrying out the conductor R&D under Mike Lamm’s leadership, with Vito Lombardo heading up the quality assurance work. And thanks very much to the whole collaboration for their work to define the science requirements that drive the experiment, which P5 has recognized as of critical importance for our field.