Test for exotic isoscalar resonance dominating ${D}^{0}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}{\ensuremath{\pi}}^{0}$ decays

Test for exotic isoscalar resonance dominating $D^{0} \to π^{+} π^{-} π^{0}$ decays

Michael Gronau and Jonathan L. Rosner

Phys. Rev. D 92, 114018 – Published 15 December 2015

Abstract

The decay $D^{0} \to π^{+} π^{-} π^{0}$ appears to be dominated by $ρ π$ states in a configuration of zero total isotopic spin. The spin $J$ , parity $P$ , and charge-conjugation eigenvalue $C$ of this final state are, therefore, $J^{P C} = 0^{- -}$ , which cannot be formed of a quark $q$ and antiquark $\bar{q}$ . If a resonance near $M (D^{0})$ dominates the final state, it must be a hybrid composed of a quark-antiquark pair and a constituent gluon, or a tetraquark $q q \bar{q} \bar{q}$ . A test for this resonance in electroproduction is proposed.