Theoretical Response to the Discovery of Deeply Bound Pionic States in 208Pb(d,3He) reactions

Recently, deeply bound pionic states were found experimentally in (d, $^3$He) reactions on $^{208}$Pb. They found an isolated peak structure in the bound region below the pion production threshold. We study theoretically these excitation functions in (d, $^3$He) reactions on $^{208}$Pb at T$_d$=600 MeV. We found very good agreement with the (d, $^3$He) excitation functions and could identify the underlying structures of the pionic states. We study the energy dependence of the (d, $^3$He) reactions and the change of the excitation functions with the incident energy.Comment: 5 pages, Latex, Figures available on request, Z.Phys.A.accepte

A critical analysis on deeply bound kaonic states in nuclei

We make a critical analysis on the theoretical calculations that lead to predictions of deeply bound kaonic states in nuclei. The model set-up, after dropping several important processes and channels, leads unavoidably to an unrealistic deep potential with a very small imaginary part. We review also the experimental results taken as reference for the claim of deeply bound kaons. We suggest that the peaks of the proton spectra come from $K^-$ absorption on a pair of nucleons, leaving the rest of the nucleons as spectators. Based on this conjecture we predict what would happen in other nuclei.Comment: 19 pags., 4 figs, version to be published in Phys. Rev.