Isotope dependence of deeply bound pionic states in Sn and Pb

We have studied the isotope dependence of deeply bound pionic states in Sn and Pb in order to examine the possibility of obtaining important information on neutron density distribution and the modification of the pion decay constant f(pi) in a nuclear medium. Formation cross sections of the pionic states are calculated in the (d,He-3) reactions. The present results indicate that the isotope dependence of the pionic states can be deduced from the experimental data with accessible energy resolution. The effects of the neutron skin for the formation cross sections are also examined and are found to affect the (d,He-3) spectra significantly.