The weak interaction of quarks between the neutron and proton have been measured for the first time by the NPDGamma experiment at the Spallation Neutron Source in Oak Ridge National Lab. UVa postdoctoral research associate Jason Fry played a leading role in the experiment along with professors Stefan Baeßler and Dinko Počanić and students. This measurement can help us understand the interplay between the strong and weak interactions in hadronic systems.

For further reading, please see the Editor's Suggestion in Physical Review Letters: 

https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.121.242002