Probing bilinear R-parity violating supergravity at the LHC

TL;DR

This paper investigates how bilinear R-parity violation in supergravity models affects supersymmetry searches at the LHC, highlighting both challenges due to reduced missing energy signals and opportunities from enhanced same-sign dilepton and trilepton events.

Contribution

It provides a detailed analysis of collider signatures of bilinear R-parity violating supergravity, including the impact on standard searches and the potential of displaced vertex detection.

Findings

R-parity violation reduces missing energy signals in SUSY searches.

Enhanced same-sign dilepton and trilepton final states improve detection prospects.

Displaced vertex searches significantly extend the parameter space coverage.

Abstract

We study the collider phenomenology of bilinear R-parity violating supergravity, the simplest effective model for supersymmetric neutrino masses accounting for the current neutrino oscillation data. At the CERN Large Hadron Collider the center-of-mass energy will be high enough to probe directly these models through the search for the superpartners of the Standard Model (SM) particles. We analyze the impact of R-parity violation on the canonical supersymmetry searches - that is, we examine how the decay of the lightest supersymmetric particle (LSP) via bilinear R-parity violating interactions degrades the average expected missing momentum of the reactions and show how this diminishes the reach in the 'usual' channels for supersymmetry searches. However, the R-parity violating interactions lead to an enhancement of the final states containing isolated same-sign di-leptons and trileptons, compensating the reach loss in the fully inclusive channel. We show how the searches for displaced vertices associated to LSP decay substantially increase the coverage in supergravity parameter space, giving the corresponding reaches for two reference luminosities of 10 and 100 fb$^{-1}$ and compare with those of the R-parity conserving minimal supergravity model.