Analysis of pion production data measured by HADES in proton-proton collisions at 1.25 GeV

Abstract

Baryon resonance production in proton-proton collisions at a kinetic beam energy of 1.25 GeV is investigated. The multi-differential data were measured by the HADES collaboration. Exclusive channels with one pion in the final state ($np\ddot{I}{€}^{+}$ and $pp\ddot{I}{€}^0$) were put to extended studies based on various observables in the framework of a one-pion exchange model and with solutions obtained within the framework of a partial wave analysis (PWA) of the Bonn-Gatchina group. The results of the PWA confirm the dominant contribution of the $\hat{I}”$(1232), yet with a sizable impact of the $N$(1440) and non-resonant partial waves.

12 pages, 6 figures