2024/09/19 by Okada, Nobuchika, Seto, Osamu · 2 citations
#Cosmology and Nongalactic Astrophysics (astro-ph.CO) #FOS: Physical sciences #High Energy Physics - Phenomenology (hep-ph)
paper · doi:10.48550/arxiv.2409.12754
We investigate the discovery potential at the MATHUSLA experiment of a long-lived particle (LLP), which is the heavier state of inelastic scalar dark matter (DM) in third generation-philic U(1) (U(1)X3) extension of the standard model. Since the heavier state and DM state form the complex scalar charged under the U(1)X3, it is natural that the heavier state P is almost degenerate with the DM state and hence long-lived. We find that third generation-philic right-handed U(1), U(1)R3, model is the most interesting, because third generation-philic models are less constrained by the current experimental results and right-handed U(1) interactions leave visible final decay products without produing neutrinos. For a benchmark of the model parameters consistent with the current phenomenological constraints, we find that the travel distance of the LLP can be O(100) m and the LLP production cross section at the 14 TeV LHC can be O(10) fb. Thus, we conclude that the LLP can be discovered at the MATHUSLA with a sufficiently large number of LLP decay events inside the MATHUSLA detector.