Giuseppe Occhialini
Born	Giuseppe Paolo Stanislao Occhialini (1907-12-05)5 December 1907 Fossombrone,Marche, Kingdom of Italy
Died	30 December 1993(1993-12-30) (aged 86)
Alma mater	University of Florence
Known for	Discovery of thepion Discovery of thepositron
Awards	Premio Presidente della Repubblica (1949) Wolf Prize in Physics (1979)
Scientific career
Fields	Particle physics
Institutions	University of Cambridge University of São Paulo University of Bristol University of Genoa University of Milan

Giuseppe Paolo Stanislao"Beppo" Occhialini (Italian:[dʒuˈzɛppeokkjaˈliːni]; 5 December 1907 – 30 December 1993) was an Italianexperimental physicist who contributed to the discovery of thepion or pi-meson decay in 1947 withCésar Lattes andCecil Powell, the latter winning theNobel Prize in Physics for this work. At the time of this discovery, they were all working in the H. H. Wills Laboratory at theUniversity of Bristol.^[1]

Giuseppe Paolo Stanislao Occhialini was born on 5 December 1907 inFossombrone, Italy, and graduated from theUniversity of Florence in 1929. In 1932, he collaborated in the discovery of thepositron incosmic rays in theCavendish Laboratory at theUniversity of Cambridge, under the leadership ofPatrick Blackett, usingcloud chambers.

Occhialini returned in Italy in 1934, where he suffered from the political climate generated byfascism. Thus, from 1937 to 1944, following an invitation byGleb Wataghin, he worked at the Institute of Physics of theUniversity of São Paulo in Brazil.

In 1944, Occhialini returned to England, working in the Wills Physics Laboratory at theUniversity of Bristol, where he studied cosmic rays. In 1947, while in Bristol, he contributed to the discovery of thepion or pi-meson decay in collaboration withCésar Lattes,Cecil Powell, andHugh Muirhead. The discovery was made using the technology of the tracks on specializedphotographic emulsions. Powell won theNobel Prize in Physics in 1950, in large part for this work.^[2]

In 1950, Occhialini returned to Italy, teaching first at theUniversity of Genoa and then in the Physics Department at theUniversity of Milan in 1952.

Occhialini was a protagonist in cosmic ray research with the nuclear utilization of photographic emulsions exposed to high energy cosmic radiation, work which culminated in 1954 with the European G-Stack collaboration, that focused on the decay products of thekaons. Later on with the coming of particle accelerators, Occhialini explored that new field of research. He also made outstanding contributions to space physics, importantly contributing to the foundation of theEuropean Space Agency.^[3]

Occhialini was an avid mountain climber. DuringWorld War II, while staying in Brazil—then a country hostile to Italy—he became an authorized alpine guide inItatiaia National Park, where there is a peak named Pico Occhialini.^{[citation needed]}

Year	Organization	Award	Citation	Ref.
1949	Accademia dei Lincei	Premio Presidente della Repubblica		[4]
1979	Wolf Foundation	Wolf Prize in Physics[a]	"For his contributions to the discovery of electron pair production and of the charged pion."	[5]

Year	Organization	Type	Ref.
1974	Royal Society	Foreign Member	[6]
1975	American Philosophical Society	International Member	[7]
1978	National Academy of Sciences	International Member	[8]

• The Department of Physics of theUniversity of Milan-Bicocca, active since 1997,^[9] is named after him.^[10]
• The satellite SAX, the first Italian satellite for the study of gamma rays, was renamedBeppoSAX from his nickname "Beppo," which is a diminutive for Giuseppe.
• Anasteroid,20081 Occhialini, was named for him.
• In 2004, Prof. Antonio Vitale,^[11] Ordinary Professor of Physics at theUniversity of Bologna, created the "Foundation Giuseppe Occhialini" with its seat at Fossombrone, birth town of Giuseppe Occhialini. The Foundation has as its objective the popularization of physics in the superior schools, and is active above all in the province of Pesaro-Urbino, where every year there is held a course with the allocation of scholarships for the worthiest students.
• In 2007, theItalian Physical Society, together with theInstitute of Physics, instituted theOcchialini Prize to honor his memory.
• On 22 June 2009, a square in Milan square was named after him, that same square where the Institute of Physics was at the time he first became professor there. The sign in the square was unveiled at a ceremony with the deans of both of Milan's state universities, Enrico Decleva and Marcello Fontanesi, Beppo's daughter Etra, and Professor Guido Vegni, one of Beppo's pupils and successors in particle physics research.

• 
  Unveiling of the Piazza Occhialini (Occhialini Square) sign, 22 June 2009, Milan, Italy
• 
  The Piazza Occhialini (Occhialini Square) sign, Milan, Italy

• Redondi, Pietro.The Scientific Legacy of Beppo Occhialini. Bologna: Società Italiana di Fisica, Springer, 2006.ISBN 978-3-540-37353-7.

Wikimedia Commons has media related toGiuseppe Occhialini.

• Giuseppe "Beppo" OcchialiniArchived 14 May 2011 at theWayback Machine. Agenzia Spaziale Italiana.
• "Ricordando Beppo" (Remembering Beppo). Video on Giuseppe Occhialini's lifeArchived 29 September 2008 at theWayback Machine. Istituto Nazionale di Astrofisica – Italy

• 1907 births
• 1993 deaths
• 20th-century Italian physicists
• Wolf Prize in Physics laureates
• Academic staff of the University of São Paulo
• Academics of the University of Bristol
• Foreign members of the Royal Society
• Foreign associates of the National Academy of Sciences
• Members of the American Philosophical Society
• Academic staff of the University of Milan
• Italian fellows of the Royal Society

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