 After the war ended in 1945 , Creutz accepted an offer from Seitz to come to the Carnegie Institute of Technology as an associate professor , and help create a nuclear physics group there . Creutz in turn recruited a number of young physicists who had worked with him at Princeton and on the Manhattan Project in Chicago and Los Alamos , including Martyn <unk> , Jack Fox , Roger Sutton and Sergio <unk> . Together , with funding from the Office of Naval Research they built a 450 MeV <unk> at the Nuclear Research Center near <unk> , Pennsylvania . For a time , This put them at the forefront of research into nuclear physics , allowing physicists there to study the recently discovered <unk> meson and <unk> meson . A visiting scholar , <unk> <unk> , created the first photographic <unk> of a meson . 
