1. General Seminars

On nuclear states of mesons

by Slawomir Wojciech Wycech (National Centre for Nuclear Studies, Warsaw, Poland)

Aula Leale (Laboratori Nazionali di Frascati)

Aula Leale

Laboratori Nazionali di Frascati

The existence of nuclear states of $\bar K$ mesons and $\eta$ mesons has been expected for about thirty years. The physical interest of this field is related to a new mechanism of nuclear binding generated by excitations of the internal nucleon structure. Despite being short lived such states might offer a new and interesting nuclear spectroscopy. Despite long and extensive experimental search, the existence and properties of such states are still elusive. Some similarities and related questions of the $\eta$ and $\bar K$ cases will be shown. Possible origin of the experimental difficulties related to weak production rate and large widths of such states will be discussed. I will try to indicate usefulness of the recent AMADEUS/KLOE measurements.