Interaction ofK+Mesons in the Interval 30-65 Mev

Abstract

A systematic study of the scattering of 1173 definitely identified $K_L$ mesons and 279 $\tau$ (including ${\tau }^{\prime }$) mesons has been made in the energy interval 30-65 Mev using photoemulsion exposed to the Berkeley $K^{+}$ meson beam. All scatterings of $K^{+}$ mesons having a projected angle greater than 2° on the emulsion plane were recorded and analyzed. The results of analysis are the following: (1) the interaction properties of the $K_L$ and $\tau$ mesons are essentially indistinguishable; (2) the coherent nuclear scattering of $K^{+}$ mesons interferes constructively with the Coulomb scattering; (3) in terms of the optical model, the best fit for coherent scattering corresponds to a real potential of ∼+15 Mev, and the inelastic scattering gives an imaginary potential of ∼3.6 Mev; (4) charge exchange is rare in this energy region: $\frac{\sigma \left(\mathrm{charge}\mathrm{exchange}\right)}{\sigma \left(\mathrm{incoherent}\right)}<\frac{1}{10}$. A tentative interpretation of the results in terms of states of isotopic spin $T=0\mathrm{}$ and $T=1\mathrm{}$ is presented. A discussion is also given on the characteristic features of $K^{+}$ stars.