Glueball string models, rotational states, and regge trajectories

A glueball model that describes excited states of glueballs and other exotic hadrons and which has the form of a closed string that features pointlike masses simulating gluons is considered. Rotational states are studied for this model. Their structure proves to be nontrivial. These states are classified, and their frequency spectrum and physical properties, including the energy and angular momentum, are determined with allowance for spin corrections. The corresponding Regge trajectories characterized by a specific set of slopes are used to describe glueball states.