S.F. Tuan

OZI-violating dipion decays of heavy quarkonia via an intermediate heavy meson pair state☆

Recent experimental data [1] for the decay ?(3s)→?+π+π show a very different pion spectrum from that of other heavy quarkonium dipion decays and confirm earlier data [2] showing that the two-pi on invariant mass distribution is flat and cannot be fit by any of the previously proposed conventional quark-gluon models for the decay [3,4,5], where the heavy quarkonium emits gluons which then either produce the two pions directly or via a bound state like a glueball or a hadronic state like the f meson [3]:

The ξ (2220) puzzle

\psi (ns) \to J/\psi + {M_{GH}} \to J/\psi + \pi + \pi

Λs(1405) and negative parity baryon states

(1a)

CP non-conservation in the decay B → Kψ

\Upsilon (ns) \to \Upsilon + {M_{GH}} \to \Upsilon + \pi + \pi

Implications of a χ(3.86) state for theoretical models

(1b) where MGH denotes either a gluon contlnuum or a bound gluonlc or hadronic meson State, or may even be any neutral even-C-even-J State 1nclud1ng new particles.

Isospin violating pion emission from heavy quarkonium

Abstract We comment on the internal consistency of recent experimental evidence for a 1 −+ M(1405) exotic meson (Alde et al.), propose experimental checks of M(1405) in other processes, and confront this meson state with some current theoretical ideas.