Cavendish Laboratory, Cambridge, February 1933: Patrick M.S. Blackett and Giuseppe P.S. (Beppo) Occhialini wrote an article for Proc. Roy. Soc. A139, 699 (1933) annoucing the results of their study of cosmic-rays shower with side, but absolutely not less important, items such as the positive electron (the positron) and the non-ionising links.
Blackett and Occhialini interpreted the positron according to Dirac’s theory as the anti-electron whose destiny was to annihilate with an electron producing one or more photons. That work provided a confirmation of the discovery of the positron by C. Anderson and explained his properties in the framework of the relativistic theory of the electron formulated by Dirac.
Willis Laboratory, Bristol, May 1947: Occhialini and Cecil C.F. Powell, in an article published by Nature, 159,694 (1947) with C.M.G. Lattes and H. Muirhead, announced the discovery of the π-meson.
University of Milan, 1952: Occhialini becomes Professor of Physics at the Institute of Physics. Research groups were founded under his leadership obtaining a great scientific production. Many professors that founded this Department were his students.