Searching for long-lived particles beyond the Standard Model at the Large Hadron Collider (original) (raw)
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Discovery prospects for long-lived multiply charged particles at the LHC
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In this work, we aim to provide a comprehensive and largely model independent investigation on prospects to detect long-lived multiply charged particles at the LHC. We consider particles with spin 0 and frac12\frac{1}{2}frac12, with electric charges in range 1le∣Q/e∣le81 \le |Q/e| \le 81le∣Q/e∣le8, which are singlet or triplet under SU(3)CSU(3)_CSU(3)C. Such particles might be produced as particle-antiparticle pairs and propagate through detectors, or form a positronium(quarkonium)-like bound state. We consider both possibilities and estimate lower mass bounds on new particles, that can be provided by ATLAS, CMS and MoEDAL experiments at the end of Run 3 and HL-LHC data taking periods. We find out that the sensitivities of ATLAS and CMS are generally stronger than those of MoEDAL at Run 3, while they may be competitive at HL-LHC for 3lesssim∣Q/e∣lesssim73 \lesssim |Q/e| \lesssim 73lesssim∣Q/e∣lesssim7 for all types of long-lived particles we consider.
Proceedings of XXVII International Workshop on Deep-Inelastic Scattering and Related Subjects — PoS(DIS2019)
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MATHUSLA: A Detector Proposal to Explore the Lifetime Frontier at the HL-LHC
arXiv: High Energy Physics - Experiment, 2019
The observation of long-lived particles at the LHC would reveal physics beyond the Standard Model, could account for the many open issues in our understanding of our universe, and conceivably point to a more complete theory of the fundamental interactions. Such long-lived particle signatures are fundamentally motivated and can appear in virtually every theoretical construct that address the Hierarchy Problem, Dark Matter, Neutrino Masses and the Baryon Asymmetry of the Universe. We describe in this document a large detector, MATHUSLA, located on the surface above an HL-LHC pppppp interaction point, that could observe long-lived particles with lifetimes up to the Big Bang Nucleosynthesis limit of 0.1 s. We also note that its large detector area allows MATHUSLA to make important contributions to cosmic ray physics. Because of the potential for making a major breakthrough in our conceptual understanding of the universe, long-lived particle searches should have the highest level of priority.