Precision spectroscopy of pionic 1s states of Sn nuclei and evidence for partial restoration of chiral symmetry in the nuclear medium

K. Suzuki, M. Fujita, H. Geissel +17

Deeply bound 1s states of ${\pi }^{-}$ in ${}^{115,119,123}$Sn were preferentially observed using the Sn($d$,${}^3$He) pion-transfer reaction under the recoil-free condition. The 1s binding e…