National Museum of Nuclear Science & History
Lew Kowarski was a Russian-born French physicist. He worked as part of the team that discovered that neutrons were emitted in the fission of uranium-235 in the 1930s, setting the groundwork for the use of nuclear chain reactions in the design of the atomic bomb.
Stanley Stewart was the Contracting Officer at Los Alamos during the Manhattan Project. After the bombings of Hiroshima and Nagasaki, Stewart wrote, “The security restrictions on our part of the work [at Los Alamos] have been more rigid than than on any other portion of the entire Manhattan Project.