Studies of the Lambda(1405) in Proton-Proton Collisions with ANKE at COSY-Juelich

TL;DR

This study investigates the Lambda(1405) resonance in proton-proton collisions at COSY-Juelich, analyzing its lineshape and position to shed light on its internal structure and compare with previous measurements.

Contribution

It provides new experimental data on the Lambda(1405) lineshape and position in pp collisions, aiding the understanding of its nature and structure.

Findings

Lambda(1405) lineshape similar to previous measurements

Position of Lambda(1405) consistent with prior data

Distinction between Lambda(1405) and Sigma0(1385) achieved

Abstract

The lineshape of the Lambda(1405) was studied in the pp -> pK+ Y0 reaction at a beam momentum of 3.65 GeV/c at COSY-Juelich. The ANKE spectrometer was used to identify two protons, one positively charged kaon, and one negatively charged pion in the final state. Invariant-mass and missing-mass techniques were applied to separate two neighbouring neutral excited hyperon resonances, the Sigma0(1385) and Lambda(1405). Both the shape and the position of the Lambda(1405) distribution are similar to those measured in other reactions and this information contributes to the ongoing debate regarding the structure of this resonance.