The Single Photon Signature of a Light Long-lived Neutralino at Remote Detectors at the LHC

TL;DR

This paper explores the detection prospects of long-lived neutralinos at various LHC remote detectors, emphasizing the importance of photon signatures from their decay in R-parity violating supersymmetry models.

Contribution

It provides a comprehensive sensitivity analysis for multiple detectors, extending previous work by including the extended flight path of parent mesons in simulations.

Findings

ANUBIS offers the highest sensitivity among the detectors.

FASER has the least sensitivity but has already collected data.

Simulation improvements enhance detection prospects for long-lived neutralinos.

Abstract

We investigate the phenomenology of light long-lived neutralinos in R-parity violating supersymmetric models, focusing on the proposed remote detectors $\texttt{ANUBIS}$, $\texttt{CODEX-b}$, $\texttt{FACET}$, $\texttt{FASER}$, $\texttt{FASER2}$, $\texttt{MAPP}$, $\texttt{MAPP2}$, and $\texttt{MATHUSLA}$ at the LHC. We assume the production of the neutralinos at the ATLAS or CMS interaction points via rare scalar meson decays induced by R-parity violating couplings. We study six supersymmetric R-parity violating benchmark scenarios in which the dominant neutralino decay is $\tilde{\chi}^0_1 \rightarrow \gamma + \nu$. For each scenario, we determine the projected search sensitivity at the above listed detectors. Extending previous work focused primarily on $\texttt{FASER}$ and $\texttt{FASER2}$, we improve the simulation by taking into account the extended flight path of the parent meson. We find that $\texttt{ANUBIS}$ provides the best sensitivity to our benchmark scenarios and $\texttt{FASER}$ the least among the considered experiments, while of course $\texttt{FASER}$ has already taken data.