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Title: Hyperon Photoproduction from Polarized H and D: towards a complete N* experiment

New complete experiments in pseudoscalar meson photo-production are being pursued at several laboratories. Here the designation of complete refers to measurements of most if not all of the possible reaction observables, of which there are 16 involving spins of the beam, target and recoil baryon. Hyperon production to Λ or Σ{sup +} final states affords attractive opportunities, since their weak decays provide an efficient self-analysis of their polarization. When the beam and target are also polarized, the resulting triple polarization measurements determine the full suite of observables with a single target orientation. This has been a focus at Jefferson Lab in the recently completed g9/FROST and g14/HDice experiments now under analysis. Multipole analyses of γp->K{sup +}Λ have been carried out with a large though incomplete set of recently published polarization data, and the uniqueness of the extracted amplitudes has been studied. Experiments with realistically achievable uncertainties require a significantly greater number of spin asymmetries than the in-principle minimum needed for a mathematical solution of the amplitude.
 [1] ;  [2]
  1. JLAB
  2. National Nuclear Data Center, Brookhaven National Laboratory, Upton, NY
Publication Date:
OSTI Identifier:
Report Number(s):
JLAB-PHY-12-1629; DOE/OR/23177-2390
DOE Contract Number:
Resource Type:
Resource Relation:
Journal Name: Nucl.Phys. A; Journal Volume: 914; Conference: HYP2012, 1-5 Oct 2012. Barcelona, Spain
Research Org:
Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)
Sponsoring Org:
USDOE Office of Science (SC)
Country of Publication:
United States
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; Meson photo-production; Baryon resonances; Multipole analysis; Polarization