Work

Deeply Bound 1s and 2p Pionic States in P205b and Determination of the s -Wave Part of the Pion-Nucleus Interaction

Year: 2002

Type: article

Abstract: We observed well-separated $1s$ and $2p$ ${\ensuremath{\pi}}^{\ensuremath{-}}$ states in ${}^{205}\mathrm{Pb}$ in the ${}^{206}\mathrm{Pb}({d,}^{3}\mathrm{He})$ reaction at ${T}_{d}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}604.3\mathrm{MeV}$. The binding energies and the widths determined are ${B}_{1s}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}6.762\ifmmode\pm\else\textpm\fi{}0.061\mathrm{MeV}$, ${\ensuremath{\Gamma}}_{1s}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}{0.764}_{\ensuremath{-}0.154}^{+0.171}\mathrm{MeV}$, ${B}_{2p}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}5.110\ifmmode\pm\else\textpm\fi{}0.045\mathrm{MeV}$, and ${\ensuremath{\Gamma}}_{2p}{\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}0.321}_{\ensuremath{-}0.062}^{+0.060}\mathrm{MeV}$. They are used to deduce the real and imaginary strengths of the $s$-wave part of the pion-nucleus interaction, which translates into a positive mass shift of ${\ensuremath{\pi}}^{\ensuremath{-}}$ in ${}^{205}\mathrm{Pb}$.

Source: Physical Review Letters

DOI: 10.1103/physrevlett.88.122301