Il Nuovo Cimento (1955-1965)

, Volume 34, Issue 5, pp 1254–1256 | Cite as

Electromagnetic mass splittings and the baryon octet mass formula

  • M. Nauenberg


It is shown that in order to take into account the electromagnetic mass shifts of the baryons in testing the baryon octet mass formula, the mean mass of each baryon isospin multiplet may be used.


Si mostra che, per tener conto gli spostamenti della massa elettromagnetica dei barioni nel verificare la formula della massa dell’ottetto barionico, si può usare la massa media di ogni multipletto di isospin del barione.


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    J. Schwinger:Phys. Rev. Lett.,12, 237 (1963); F. Gursey, T. D. Lee and M. Nauenberg:Phys. Rev. (to be published). Let the I=1/2 component of the fundamental fermion triplet have electromagnetic mass shifts δm1 and δm2 for I3=1/2 and -1/2 respectively, and correspondingly δμ1 and δμ2 for the boson triplet. If we assume that the baryon electromagnetic mass shifts are simply the sum of the shifts of their components (justified in the case of weak binding) we obtain δΣ+=δm1+δμ2, δΣ-=δm2+δμ1 and δΣ0 = 1/2 (δm1^+δm2+δμ1 + δμ2) leading to eq. (5). The relations given in eq. (2) are also readily obtained in this manner, if we note that the electromagnetic mass shift δm0 and δμ0 of the δ=0 member of the fermion and boson triplets satisfies the condition δm0 = δm2 and δμ0=δμ2 respectively. A similar argument has been proposed independently by G. Zweig (CERN preprint).ADSCrossRefGoogle Scholar

Copyright information

© Società Italiana di Fisica 1964

Authors and Affiliations

  • M. Nauenberg
    • 1
  1. 1.CERNGeneva

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