https://doi.org/10.1140/epjc/s10052-018-6529-y
Regular Article - Theoretical Physics
Effective field theory in the study of long range nuclear parity violation on lattice
1
CAS Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing, 100190, China
2
School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
3
INPAC, Shanghai Key Laboratory for Particle Physics and Cosmology, MOE Key Laboratory for Particle Physics, Astrophysics and Cosmology, School of Physics and Astronomy, Shanghai Jiao-Tong University, Shanghai, 200240, China
* e-mail: cseng@hiskp.uni-bonn.de
Received:
19
October
2018
Accepted:
20
December
2018
Published online:
14
January
2019
A non-zero signal 
of the gamma-ray asymmetry in the neutron-proton capture was recently reported by the NPDGamma Collaboration which provides the first determination of the 
parity-odd pion-nucleon coupling constant 
. The ability to reproduce this value from first principles serves as a direct test of our current understanding of the interplay between the strong and weak interaction at low energy. To motivate new lattice studies of 
, we review the current status of the theoretical understanding of this coupling, which includes our recent work that relates it to a nucleon mass-splitting by a soft-pion theorem. We further investigate the possibility of calculating the mass-splitting on the lattice by providing effective field theory parameterizations of all the involved quark contraction diagrams. We show that the lattice calculations of the easier connected diagrams will provide information of the chiral logarithms in the much harder quark loop diagrams and thus help in the chiral extrapolation of the latter.
© The Author(s), 2019
