Pion-assisted Nucleon-Delta and Delta-Delta dibaryons

TL;DR

This paper reviews and reports new hadronic calculations of N-Delta and Delta-Delta dibaryons, identifying candidate states and explaining recent experimental observations through relativistic Faddeev equations involving pions, nucleons, and Deltas.

Contribution

It provides the first hadronic calculations reproducing the small width of the D_{03}(2370) dibaryon and predicts properties of its exotic partner D_{30}.

Findings

Identification of N-Delta and Delta-Delta dibaryon candidates.

Reproduction of D_{03}(2370) width (~70 MeV).

Predictions for D_{30} properties.

Abstract

N-Delta and Delta-Delta dibaryon candidates are discussed and related quark-based calculations are reviewed. New hadronic calculations of L=0 nonstrange dibaryon candidates are reported. For N-Delta, I(JP)=1(2+) and 2(1+) S-matrix poles slightly below threshold are found by solving pi-N-N Faddeev equations with relativistic kinematics, and for Delta-Delta several S-matrix poles below threshold are found by solving pi-N-Delta Faddeev equations with relativistic kinematics in which the N-Delta interaction is dominated by the 1(2+) and 2(1+) resonating channels. In particular, the I(JP)=0(3+) Delta-Delta dibaryon candidate D_{03}(2370) observed recently by the WASA@COSY Collaboration is naturally explained in terms of long-range physics dominated by pions, nucleons and Delta's. These calculations are so far the only ones to reproduce the relatively small width, approximately 70 MeV, of D_{03}(2370). Predictions are also made for the location and width of D_{30}, the I(JP)=3(0+) exotic partner of D_{03}(2370).