Evidence of kaon nuclear and Coulomb potential effects on soft K+   production from nuclei
  The ratio of forward K+ production on copper, silver and gold targets to that on carbon has been measured at proton beam energies between 1.5 and 2.3 GeV as a function of the kaon momentum p_K using the ANKE spectrometer at COSY-Juelich. The strong suppression in the ratios observed for p_K<200-250 MeV/c can be ascribed to a combination of Coulomb and nuclear repulsion in the K+A system. This opens a new way to investigate the interaction of K+-mesons in the nuclear medium. Our data are consistent with a K+A nuclear potential of V_K~20 MeV at low kaon momenta and normal nuclear density. Given the sensitivity of the data to the kaon potential, the current experimental precision might allow one to determine V_K to better than 3 MeV. 
M.Nekipelov, M.Buescher, W.Cassing, M.Hartmann, V.Hejny, V.Kleber,   H.R.Koch, V.Koptev, Y.Maeda, R.Maier, S.Merzliakov, S.M...