Status of experimental investigations of $\eta$-mesic nuclei

Abstract

Short history of ideas concerning a possible existence of bound states of the $\eta$-meson and a nucleus is considered. First experiments at BNL and LAMPF on searching for these states are discussed. Another recent experiment using the photon beam of the 1 GeV electron synchrotron of LPI is described. Possible experiments on studying $\eta$-mesic nuclei using a proton beam (at Nuclotron of Dubna) and a $\gamma$-beam (CEBAF, JLAB) are suggested.