Meson Spectroscopy and the Search for Exotics

. I will review the current status of exotic hadrons in the meson sector. There is currently strong evidence that a scalar glueball mixed into the normal scalar mesons has been found. There is also an interesting candidate for the tensor glueball state. Finally, I will discuss hybrid mesons with explicitly exotic quantum numbers. INTRODUCTION In the context of this paper I will review the current status of exotic mesons; glueballs and hybrid mesons. Our current best evidence for a glueball comes from the scalar meson sector, J PC = 0 ++ . In this sector there appears to be two states, the f 0 (1500) and f 0 (1750) which are produced in several glue--rich mechanisms. The decay rates of the f 0 (1500) have been studied in detail by the Crystal Barrel experiment which finds that this state cannot be explained as either a pure glueball nor a pure meson. The f 0 (1500) combined with the f 0 (1750) leads us to the interpretation that these states are mixtures of both glueball and normal...