Fredrick “Fred” D. Johnson was a research assistant at the University of Chicago’s Metallurgical Laboratory (“Met Lab”) during the Manhattan Project.
On March 6, 1944, Johnson was transferred from Section C-II to Baumbach’s plutonium metal production group (Group 6). (Seaborg, Vol. 2, p. 463). In June 1944, Johnson became part of Group 6A, a group related to plutonium metal production that focused on high vacuum techniques. (Seaborg, Vol. 3, p 152). Johnson was transferred to the Physics Division from Section C-I in the Chemistry Division on October 9, 1944 (Seaborg, Vol. 3 p 276).
For more information about Fredrick “Fred” D. Johnson and personnel at the Met Lab, please see the following references: