Revisiting η′(958) nuclear states

Abstract

Observing ${\eta }^{\prime }$-nuclear quasibound states requires that the ${\eta }^{\prime }$-nuclear potential is both sufficiently attractive and weakly absorptive, as confirmed by the CBELSA/TAPS collaboration analysis of inclusive ${\eta }^{\prime }$ production experiments on nuclear targets, including liquid hydrogen (LH${}_2$). Here we present an alternative derivation of the ${\eta }^{\prime }$-nuclear potential, constrained by near-threshold $pp\to pp{\eta }^{\prime }$ and $\gamma p\to {\eta }^{\prime }p$ production experiments on a free proton. The resulting ${\eta }^{\prime }$-nuclear potential is weakly attractive and strongly absorptive, to the extent that observation of clear signals of ${\eta }^{\prime }$-nuclear quasibound states is unlikely. Possible exceptions resulting from the dynamics of the nearby $I=\frac{1}{2}$$J^{\pi }={\left(\frac{1}{2}\right)}^{-}$ nucleon resonance $N^{*}$(1895) are briefly discussed.