Glueball-meson molecules

Experimental searches for pure glueball states have proven challenging and so far yielded no results. This is believed to occur because glueballs mix with the ordinary qq over bar states with the same quantum numbers. We will discuss an alternative mechanism, the formation of the glueball-meson molecular states. We will argue that the wave functions of already observed excited meson states may contain a significant part due to such molecular states. We discuss the phenomenology of glueball-meson molecules and comment on a possible charmless component of the XY Z states. & COPY; 2023 The Author. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons .org /licenses /by /4 .0/). Funded by SCOAP3.

Automated summary

Experimental searches for pure glueball states have been challenging and yielded no results so far. It is believed that glueballs mix with ordinary qq over bar states with the same quantum numbers. The formation of glueball-meson molecular states is proposed as an alternative mechanism. It is argued that the wave functions of already observed excited meson states might include a significant part due to such molecular states.