A Fast Track towards the `Higgs' Spin and Parity

TL;DR

This paper proposes a rapid method to determine the spin and parity of the Higgs boson by analyzing invariant-mass distributions in Higgs-strahlung events at colliders, aiding quick identification of its quantum properties.

Contribution

It introduces a new approach using invariant-mass distributions in Higgs-strahlung to quickly distinguish Higgs spin-parity hypotheses at colliders.

Findings

Invariant-mass distributions differ significantly for different J^P hypotheses.

Simulation results show the method can rapidly identify the Higgs' spin and parity.

The approach is feasible with current collider data and analysis tools.

Abstract

The LHC experiments ATLAS and CMS have discovered a new boson that resembles the long-sought Higgs boson: it cannot have spin one, and has couplings to other particles that increase with their masses, but the spin and parity remain to be determined. We show here that the `Higgs' + gauge boson invariant-mass distribution in `Higgs'-strahlung events at the Tevatron or the LHC would be very different under the J^P = 0+, 0- and 2+ hypotheses, and could provide a fast-track indicator of the `Higgs' spin and parity. Our analysis is based on simulations of the experimental event selections and cuts using PYTHIA and Delphes, and incorporates statistical samples of `toy' experiments.