Baryon spectroscopy with polarization observables from CLAS

TL;DR

This paper discusses polarization observables measured in photoproduction experiments at CLAS, which are crucial for understanding the complex spectrum of nucleon excitations and resonances.

Contribution

It presents new polarization measurements from CLAS experiments that provide essential constraints for partial-wave analyses of nucleon resonances.

Findings

Enhanced constraints on nucleon resonance spectrum

Identification of polarization effects in photoproduction

Improved partial-wave analysis accuracy

Abstract

The spectrum of nucleon excitations is dominated by broad and overlapping resonances. Polarization observables in photoproduction reactions are key in the study of these excitations. They give indispensable constraints to partial-wave analyses and help clarify the spectrum. A series of polarized photoproduction experiments have been performed at the Thomas Jefferson National Accelerator Facility with the CEBAF Large Acceptance Spectrometer (CLAS). These measurements include data with linearly and circularly polarized tagged-photon beams, longitudinally and transversely polarized proton and deuterium targets, and recoil polarizations through the observation of the weak decay of hyperons. An overview of these studies and recent results will be given.