Mikayel Dabaghyan
University of  New Hampshire/ Los Alamos National Lab
September 5, 2007

TITLE:  Measurement of Parity Violation in Cold Neutron Capture	

ABSTRACT:  The NPDGamma experiment has gone through the first phase at 
the Los Alamos Neutron Science Center (LANCSE).  The experiment measures 
the directional asymmetry of the gamma ray emission with respect to the 
neutron spin in the process of radiative neutron capture on protons. This 
asymmetry is a direct measure of the pion-nucleon coupling constant that 
quantifies the pion-exchange part of the weak Hamiltonian of the N-N 
interactions. The measurement will serve as a test of the theory that 
describes the N-N interaction in terms of a meson exchange as well as 
allow to probe the low energy QCD.  
      During the commissioning runs as well as the first production period, 
various aspects of the experimental setup were investigated in order to 
ensure the ability of the apparatus to measure a very small gamma ray asymmetry. 
The experiment and the preliminary results will be discussed.