Baryon spectroscopy with polarization observables from CLAS

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.

arXiv commentContribution to the Proceedings of the Workshop "Nucleon Resonances: From Photoproduction to High Photon Virtualities", October 12 - October 16, 2015, ECT*, Trento; submitted to the Few-Body Systems. arXiv admin note: text overlap with arXiv:1510.08000

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