R-parity Violation and Light Neutralinos at CODEX-b, FASER, and MATHUSLA

TL;DR

This paper evaluates the potential of upcoming LHC detectors to discover long-lived light neutralinos produced via meson decays in R-parity-violating supersymmetry, offering model-independent sensitivity estimates.

Contribution

It provides the first comprehensive sensitivity analysis of CODEX-b, FASER, and MATHUSLA for detecting long-lived neutralinos from meson decays, including model-independent results.

Findings

Detectors can probe new parameter space for light neutralinos.

Sensitivity varies depending on the detector and decay channels.

Results are applicable to any long-lived particle in the GeV mass range.

Abstract

The $LQ\bar D$ operator in R-parity-violating supersymmetry can lead to meson decays to light neutralinos and neutralino decays to lighter mesons, with a long lifetime. Since the high-luminosity LHC is expected to accumulate as much as 3/ab of data, several detectors proposed to be built at the LHC may probe unexplored regions in the parameter space, for long-lived neutralinos. We estimate the sensitivity of the recently proposed detectors, CODEX-b, FASER, and MATHUSLA, for detecting such light neutralinos singly produced from $D$- and $B$-meson decays in a list of benchmark scenarios, and discuss the advantages and disadvantages of the proposed detectors in this context. We also present our results in a model independent fashion, which can be applied to any long-lived particle with mass in the GeV regime.