Josef 'Sepp' Schintlmeister was an Austrian-German nuclear physicist and alpinist from Radstadt. During World War II, he worked on the German nuclear energy project, also known as the Uranium Club. After World War II, he was sent Russia to work on the Soviet atomic bomb project. After he returned to Vienna, he took positions in East Germany. He was a professor of physics at the Technische Hochschule Dresden as well holding a leading scientific position at the Rossendorf Central Institute for Nuclear Research.

Radstadt is a historic town in the district of St. Johann im Pongau in the Austrian state of Salzburg.