Institutsseminar Kern- und Hadronenphysik

Feb. 14, 2011 at 5 p.m. c.t. in HS Kernphysik, Becherweg 45

Prof. Dr. Michael Ostrick
Institut für Kernphysik
ostrick@kph.uni-mainz.de

Electromagnetic Pion Production and Decay Experiments; Testing QCD Symmetries
A.M. Bernstein (Physics Department and Laboratory for Nuclear Science, MIT)


A new measurement of the lifetime of the neutral pi meson will be presented. This tests a prediction due to the axial anomaly of QCD, modified by a small isospin breaking chiral correction.

Low energy pi-N scattering and electromagnetic pion production predictions are based on the spontaneous breaking of chiral symmetry in QCD. In addition to tests of this theory, new experiments being conducted with polarized targets are sensitive to the final state pi-N interactions and sensitive to isospin breaking effects. Recent developments in this field, along with a future outlook for theory and experiment, will be presented.