Reconstructing the invariant mass of spin-2 particles decaying into diphoton in association with a dijet

Abstract

The Standard Model (SM) of particle physics, though highly successful, fails to incorporate gravity, which is hypothesized to be mediated by a spin-2 particle known as the graviton. This study explores the production and decay of a hypothesized generic massive spin-2 particle, Y2, following a model proposed by Das et al. We focus on the pp → Y2 + jj channel, where Y2 decays into a diphoton pair. Event generation is performed using MadGraph5_aMC@NLO, interfaced with Pythia 8.307, which is followed by analysis and visualization via Rivet 3.1.7. The isolation algorithm for photons effectively “cleans” the signal, yielding clear reconstructed mass peaks for Y2. We analyzed the reconstructed mass and the azimuthal angle between the diphotons for various Y2 mass values. Our results show a high distribution of final state diphotons having an azimuthal separation of 2 to 3.1 radians, indicating a near-antiparallel direction of the decay products in the transverse plane of the collider. Signal-background comparisons demonstrate that the chosen background has a significantly lower cross-section after the algorithm was employed, thus, it is not a dominant background for the process. This work allows for further studies on more general backgrounds, enhancing the search for spin-2 particles in high-energy collisions.