Sensitivity of the COSY Dibaryon Candidate to np Elastic Scattering Measurements

Abstract

The case for a dibaryon resonance, appearing in np scattering, has support from a WASA-at-COSY measurement of the polarization quantity A_y over a center-of-mass energy region suggested by structures seen earlier in two-pion production experiments. Here we compare fits with and without an associated pole in order to clarify the impact of these COSY data. We then consider what further np scattering measurements would most clearly distinguish between the pole and non-pole fit results.

Comments: 7 pages, 7 figures, 1 table; added 1 figure and made small text polishing