Superconvergent Dispersion Relations andI=2Electromagnetic Mass Differences of Hadrons

Abstract

Explicit calculations have been presented for the $I=2\mathrm{}$ electromagnetic mass difference between particles of a given isomultiplet using the superconvergent-dispersion-relation approach suggested by Harari. We obtain, in particular, the electromagnetic mass differences (i) ${\pi }^{+}-{\pi }^0$, (ii) ${\rho }^{+}-{\rho }^0$, (iii) ${\Sigma }^{+}+{\Sigma }^{-}-2\mathrm{}{\Sigma }^0$, (iv) $N^{*++}+N^{*0\mathrm{}}-2\mathrm{}{N}^{*+}$, and (v) ${Y_1}^{*+}+{Y_1}^{*+}-2\mathrm{}{Y_1}^{*0\mathrm{}}$. The agreement of our results with experiments is excellent.