Louis Rosen (1918-2009) was an American physicist.
A native New Yorker and the son of Polish immigrants, Rosen was personally selected to work on the Manhattan project in Los Alamos while a graduate student in physics at the Pennsylvania State University. Once at Los Alamos, Rosen was assigned to Edwin McMillan’s group, where he worked on implosion technology.
Rosen remained in Los Alamos after the war ended and was considered the father of the Los Alamos Meson Physics Facility. He played a key role in the lab’s research after the war.