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Title: Symmetry tests in photo-pion production

Small angle electron scattering with intense electron beams opens up the possibility of performing almost real photon induced reactions with thin, polarized hydrogen and few body targets, allowing for the detection of low energy charged particles. This promises to be much more effective than conventional photon tagging techniques. For photo-pion reactions some fundamental new possibilities include: tests of charge symmetry in the N-N system by measurement of the neutron-neutron scattering length a{sub nn} in the and ggrD → π{sup +}nn reaction; tests of isospin breaking due to the mass difference of the up and down quarks; measurements with polarized targets are sensitive to πN phase shifts and will test the validity of the Fermi-Watson (final state interaction) theorem. All of these experiments will test the accuracy and energy region of validity of chiral effective theories.
Authors:
 [1]
  1. Physics Dept. and Laboratory for Nuclear Science Massachusetts Institute of Technology Cambridge MA. 02139 (United States)
Publication Date:
OSTI Identifier:
22280670
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 1563; Journal Issue: 1; Conference: Workshop to explore physics opportunities with intense, polarized electron beams at 50-300 MeV, Cambridge, MA (United States), 14-16 Mar 2013; Other Information: (c) 2013 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; CHARGED PARTICLES; CHIRALITY; D QUARKS; ELECTRON BEAMS; ELECTRON REACTIONS; ELECTRONS; FINAL-STATE INTERACTIONS; ISOSPIN; MASS DIFFERENCE; NEUTRON-NEUTRON INTERACTIONS; PARTICLE IDENTIFICATION; PARTICLE PRODUCTION; PHOTONS; PION REACTIONS; POLARIZED TARGETS; U QUARKS