Helicity and nuclear $\beta$ decay correlations
  We present simple derivations of nuclear $\beta$-decay correlations with an emphasis on the special role of helicity. This provides a good opportunity to teach students about helicity and chirality in particle physics through exercises using simple aspects of quantum mechanics. In addition, this paper serves as an introduction to nuclear $\beta$-decay correlations from both a theoretical and experimental vantage. This article can be used to introduce students to ongoing experiments searching for hints of new physics in the low-energy precision frontier. 
Ran Hong and Matthew G. Sternberg and Alejandro Garc\'ia
physics.ed-ph nucl-th