Optimizing Polar Asymmetry Observables at Colliders

Polar angle asymmetries are simple, intuitive, model-independent observables for spin identification of new physics at colliders. We argue that the second moment of the normalized polar differential cross section is typically optimal in the case of Drell-Yan boson resonances at \textit{pp }colliders. Our arguments are based on explicitly investigating a range of angular weight functions of the decay of spin 0,1,2 bosons to massless spin 1/2 or 1 particles.