Mu2e celebrates completion of new experimental hall

The Mu2e collaboration celebrates the completion of their experimental hall. Photo: Reidar Hahn

Earlier this year Mu2e celebrated an important milestone – the completion of a new building to house the experimental apparatus and its supporting infrastructure. The Mu2e building is located just south of Wilson Hall on Fermilab’s new Muon Campus, which is also home to the MC-1 building that hosts the Muon g-2 experiment.

With over 22,000 square feet of floor space, the Mu2e experimental hall is not your normal building. It is oddly shaped with many nooks, crannies, feedthroughs and labyrinths to accommodate the S-shaped apparatus (see lower figure) and the cryogenic, electrical, cooling, controls and data acquisition systems required for safe and efficient operations.

This figure shows an exploded view of the Mu2e experimental hall with the magnet system installed in the lower level.

The ground floor features a high-bay area large enough to receive and offload the largest pieces of the Mu2e experiment – the components of the magnet system that will snake through the downstairs hall. Installation of Mu2e’s magnets will occur in four stages and will use a pair of 30-ton cranes that can operate separately or in tandem. To install Mu2e in its entirety will require up to six separate hatches to lower down various pieces of the accelerator beamline, magnet system, detector elements and thousands of tons of radiation shielding.

The underground portion of the building will house the Mu2e apparatus and part of the beamline that will deliver protons to the experiment. It also hosts a large room that will contain a robot for changing the Mu2e production target when necessary. In order to ensure the Mu2e magnet systems stay aligned over the lifetime of the experiment, the floor on the lower level is a single reinforced concrete slab four feet thick.

In total the Mu2e building required the excavation of nearly 100,000 cubic yards of earth and is constructed of about 16,000 cubic yards of reinforced concrete weighing nearly 65 million pounds, 600 tons of structural steel, and needed 75,000 person-hours of work. From start to finish the construction took two years and was overseen by Tom Hamernik, Tom Lackowski and Tim Trout of FESS.

Over the next two years Mu2e will install the support systems needed to operate the experiment. The installation of the magnet systems begins in 2019, and commissioning of the beam delivery systems is scheduled to begin in 2020.

Doug Glenzinski is a co-spokesperson for the Mu2e experiment.