The d⁎(2380) dibaryon resonance width and decay branching ratios

Attempts to reproduce theoretically the width Γd⁎=80±10 MeV of the I(JP)=0(3+)d⁎(2380) dibaryon resonance established by the WASA-at-COSY Collaboration are discussed. The validity of associating the d⁎(2380) in quark-based models exclusively with a tightly bound ΔΔ configuration is questioned. The d⁎(2380) width and decay branching ratios into NNππ, NNπ and NN final states are studied within the Gal-Garcilazo hadronic model in which the d⁎(2380) is a πNΔ resonance embedded in the NNππ continuum some 80 MeV below the ΔΔ threshold. In particular, predictions are made for the branching ratios of the unobserved yet d⁎(2380)→NNπ decays which are suppressed in a purely-ΔΔ dibaryon model. A possible connection of the ABC effect observed in the pn→d⁎→dπ0π0 resonance reaction to the d⁎(2380) dibaryon is noted.