Frank Ross served in the Army at Los Alamos during the Manhattan Project.
Dick Kosh was an American physicist. He worked at the Los Alamos site during the war, arriving from the University of Wisconsin, Madison, and then stayed afterwards.
Owen Chamberlain (1920-2006) was an American physicist and winner of the 1959 Nobel Prize. He joined the Manhattan Project in 1942 after his graduate studies were interrupted by World War II.