Isotensor Dibaryon in the $pp\ensuremath{\rightarrow}pp{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$ Reaction?

Isotensor Dibaryon in the $p p \to p p π^{+} π^{-}$ Reaction?

P. Adlarson et al. (WASA-at-COSY Collaboration)

Phys. Rev. Lett. 121, 052001 – Published 1 August 2018

Abstract

Exclusive measurements of the quasifree $p p \to p p π^{+} π^{-}$ reaction have been carried out at WASA@COSY by means of $p d$ collisions at $T_{p} = 1.2 GeV$ . Total and differential cross sections have been extracted covering the energy region $T_{p} = 1.08 - 1.36 GeV$ , which is the region of $N^{*} (1440)$ and $Δ (1232) Δ (1232)$ resonance excitations. Calculations describing these excitations by $t$ -channel meson exchange are at variance with the measured differential cross sections and underpredict substantially the experimental total cross section. An isotensor $Δ N$ dibaryon resonance with $I (J^{P}) = 2 (1^{+})$ produced associatedly with a pion is able to overcome these deficiencies.