The Analysis Status of Σ+ p Scattering Events in the J-PARC E40 Experiment

The J-PARC E40 experiment aims for measuring cross sections of the Sigma p scatterings with high statistics by overcoming difficulties of hyperon-nucleon scattering experiment. The physics motivations are to verify the large repulsive force due to quark Pauli effect in the Sigma(+) p interaction and to perform systematic study of the Sigma N interaction. Physics data taking was performed at the K1.8 beam line in the J-PARC hadron experimental facility by 2020 June. Sigma(+) particles were produced via the pi(+)p -> K+Sigma(+) reaction and their momenta were tagged with spectrometers. Recoil proton of the Sigma(+) p scatterings and proton from the Sigma(+) -> p pi(0) decay were detected with surrounding detector system CATCH. The Sigma(+) p scattering can be identified by checking the consistency for the recoil proton between the measured energy and the calculated energy from kinematics of the Sigma(+) p scattering. In present analysis, 69M Sigma(+) particles are tagged as the Sigma(+) beam and 4500 Sigma(+) p scattering events are identified. Further analysis to derive the differential cross sections is ongoing.

Automated summary

The J-PARC E40 experiment aims to measure cross sections of Sigma p scatterings, verify characteristics of Sigma(+) p interaction, and conduct systematic study. The experiment was conducted in June 2020 at J-PARC, generating Sigma(+) particles through a specific reaction and measuring with detector systems.