Exploring the Hidden Valley at MATHUSLA

TL;DR

This paper evaluates MATHUSLA's potential to detect long-lived particles predicted by hidden valley models, especially those with low energy signatures that challenge traditional collider searches.

Contribution

It provides a detailed assessment of MATHUSLA's sensitivity to hidden valley scenarios, modeling particle showering and detector acceptance for the first time.

Findings

MATHUSLA can probe new parameter space in hidden valley models.

Detector acceptance depends on hidden valley meson lifetime.

MATHUSLA is effective for low energy, long-lived particle detection.

Abstract

Hidden valley models naturally predict numerous long-lived particles, the distinctive signatures of which would be compelling evidence for a hidden valley scenario. As these are typically low energy particles, they pose a challenge in terms of passing energy triggers in traditional searches at the Large Hadron Collider. The MATHUSLA experiment is specifically designed for the purpose of detecting long-lived particles. It also has the capability of detecting lower energy particles relative to ATLAS and CMS. In this paper, we assess MATHUSLA's potential for effectively probing hidden valley models. As a benchmark, we assume the hidden valley sector communicates with Standard Model sectors via a heavy vector propagator that couples to Standard Model quarks as well as hidden valley quarks. We model the showering and hadronization in the hidden valley sector using PYTHIA, and study the detector acceptance as a function of the hidden valley meson's lifetime. We find that MATHUSLA possesses significant capabilities to explore previously uncharted parameter space within hidden valley models.