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DISCOVERY OF THE POSITRON
The Positive Electron "On August 2, 1932, during the course of photographing cosmic-ray tracks... the tracks shown in Fig. 1 were obtained, which seemed to be interpretable only on the basis of the existence in this case of a particle carrying a positive charge but having a mass of the same order of magnitude as that normally possessed by a free negative electron... It is concluded, therefore, that the magnitude of the charge of the positive electron which we shall henceforth contract to positron is very probably equal to that of a free negative electron which from symmetry considerations would naturally be called a negatron." -Carl AndersonFIRST EDITION IN ORIGINAL WRAPPERS of Carl Anderson's announcement of the discovery of the positron, the first antiparticle. "Anderson received his Ph.D. in 1930 from the California Institute of Technology, Pasadena, where he worked with physicist Robert Andrews Millikan. Having studied X-ray photoelectrons (electrons ejected from atoms by interaction with high-energy photons) since 1927, he began research in 1930 on gamma rays and cosmic rays. While studying cloud-chamber photographs of cosmic rays, Anderson found a number of tracks whose orientation suggested that they were caused by positively charged particles—but particles too small to be protons. In 1932 he announced that they were caused by positrons, positively charged particles with the same mass as electrons. The claim was controversial until verified the next year by British physicist Patrick M.S. Blackett and Italian Giuseppe Occhialini" (Britannica). Anderson won the 1936 Nobel Prize "for his discovery of the positron." Particle Physics... An Annotated Bibliography: "Discovery of the positron, the first antiparticle, predicted by Dirac." In The Physical Review, Second Series, Volume 43, Number 6, pp. 491-494. Lancaster, PA, 1933. Quarto, the complete issue in original printed wrappers; custom cloth box. With four photographic illustrations of the cloud chambers. Minor bump to top corner, otherwise a fine copy in original wrappers. $2100. |
