Linear Mass Relations for the Elementary Particles and Resonant States

Previous work on linear mass relations for elementary particles has been extended, particularly in connection with several resonant states which have been discovered recently. Two observed resonant states with baryon number $B=2$ satisfy very simple mass relations which give support to the compound (quasinucleus) model discussed previously. In terms of the compound model, an interesting regularity has been noticed concerning compounds formed from the $K$ and $\ensuremath{\eta}$ mesons and members of the baryon octet ($N$, $\ensuremath{\Lambda}$, $\ensuremath{\Sigma}$, $\ensuremath{\Xi}$). We have also made a study of mass relations involving the recently discovered mesons and baryon isobars, in particular the particles ${\ensuremath{\epsilon}}^{0}(700)$, $D(1280)$, ${K}^{*}(1400)$, ${f}^{*}(\ensuremath{\sim}1500)$, and ${{N}_{\frac{1}{2}}}^{*}(1400)$.