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  • Open Access

Updated sensitivities to heavy neutral leptons at the LHC far detectors and SHiP

Zeren Simon Wang* and Yu Zhang†

  • *Contact author: wzs@hfut.edu.cn
  • †Contact author: dayu@hfut.edu.cn
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Phys. Rev. D 113, 075024 – Published 17 April, 2026

DOI: https://doi.org/10.1103/fyd4-gk83

Abstract

In recent years, a number of experiments dedicated to searches for long-lived particles (LLPs) have been proposed or approved, or have entered operation. While the sensitivities of these experiments to various LLP scenarios have been extensively studied, key aspects—such as detector geometries, background estimates, and projected operational durations—for several facilities, including MATHUSLA, ANUBIS, and SHiP, have undergone significant updates. In this work, we implement the latest experimental designs in the Displaced Decay Counter tool for calculating detector acceptances and signal-event yields, and reevaluate their sensitivity reach to one of the most widely studied LLP scenarios, namely minimal heavy neutral leptons.

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Phys. Rev. D 113, 075024– Published 17 April, 2026
  • Received 28 January 2026
  • Accepted 25 March 2026
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