Revisiting Universal Extra-Dimension Model with Gravity Mediated Decays

TL;DR

This paper investigates the collider signatures of a fat-brane Universal Extra Dimension model with gravity-mediated decays, updating constraints with LHC data and proposing machine learning techniques for improved detection.

Contribution

It introduces a novel collider phenomenology analysis of fat-brane mUED, updating constraints and developing machine learning strategies for better signal identification.

Findings

Updated constraints on fat-brane mUED from LHC data

Proposed machine learning methods to improve detection sensitivity

Enhanced strategies for future collider searches

Abstract

We explore the collider phenomenology of the fat-brane realization of the Minimal Universal Extra Dimension (mUED) model, where Standard Model (SM) fields propagate in a small extra dimension while gravity accesses additional large extra dimensions. This configuration allows for gravity-mediated decay (GMD) of Kaluza-Klein (KK) particles, resulting in unique final states with hard photons, jets, massive SM bosons, and large missing transverse energy due to invisible KK gravitons. We derive updated constraints on the model's parameter space by recasting ATLAS mono-photon, di-photon, and multi-jet search results using 139 inverse femtobern of integrated luminosity data. Recognizing that current LHC search strategies are tailored for supersymmetric scenarios and may not fully capture the distinct signatures, we propose optimized strategies using machine learning algorithms to tag boosted SM bosons and enhance signal discrimination against SM backgrounds. These methods improve sensitivity to fat-brane mUED signatures and offer promising prospects for probing this model in future LHC runs.