Measuring the longest range P-odd pion-nucleon coupling in pion photoproton production near the threshold

J.-W. Chen

University of Maryland

The longest range P-odd pion-nucleon coupling hp is important for low energy non-leptonic parity violation. However, after considerable effort in the past two decades, its value is still poorly constrained largely due to many-body theoretical complications. It will be shown that the single nucleon process, polarized gamma p -> p+ n in the threshold region, is an excellent candidate for measuring h_pi to an uncertainty of 20% if it has a natural size from dimensional analysis.