Photo from the Nobel Foundation archive.
Patrick Maynard Stuart Blackett
The Nobel Prize in Physics 1948
Born: 18 November 1897, London, United Kingdom
Died: 13 July 1974, London, United Kingdom
Affiliation at the time of the award: Victoria University, Manchester, United Kingdom
Prize motivation: "for his development of the Wilson cloud chamber method, and his discoveries therewith in the fields of nuclear physics and cosmic radiation."
Prize share: 1/1
The cloud chamber is an instrument in which tiny electrically-charged particles that pass through super-saturated air leave trails behind them. Patrick Blackett used the cloud chamber for groundbreaking studies of particles from the cosmos and from nuclear reactions. In 1932 Patrick Blackett and Giuseppe Occhialini connected the cloud chamber to a Geiger counter, which detects the passage of a particle. In this way a picture could be captured precisely when a particle passed by. Patrick Blackett showed, among other things, that with the application of high energy, pairs of electrons and positrons could be formed out of light particles, photons.