Addendum to Distinguishing Spins in Decay Chains at the Large Hadron Collider.

Abstract

We extend our earlier study of spin correlations in the decay chain D ! Cq, C ! Blnear, B ! Alfar, where A,B,C,D are new particles with known masses but undetermined spins, lnear and lfar are opposite-sign same-flavour charged leptons and A is invisible. Instead of looking at the observable 2- and 3-particle invariant mass distributions separately, we compare the full three-dimensional phase space distributions for all possible spin assignments of the new particles, and show that this enhances their distinguishability using a quantitative measure known as the Kullback-Leibler distance.