Physics Research Laboratory / Nuclear Physics Laborator
On March 1, 1946, the University received contract N6ORI-071(01) from the Department of the Navy, Office of Naval Research, for support of nuclear physics research. Between March 1, 1946 and December 31, 1955, the University received $3,661,636 from the contract, whose "work specifications [were] very broad, enabling University scientists to do research in any area of nuclear physics" and supported the betatron and cyclotron. 
Located in south campus, next to Central Food Stores, the Nuclear Physics Laboratory was completed to give the burgeoning nuclear physics department more room. Completed between 1946 and 1947, it cost $1,500,000 and  was designed by Ernest L. Stouffer, University Architect, with C. A. Petry & Sons handling the general contracting. 
The Betatron was moved from Abbott Power Plant to the Physics Research Laboratory when it opened in 1947 and a larger betatron was also constructed in the building in 1950.