2023/12/18 by Wei Liu, Frank F. Deppisch, Liu, Wei +2
Physics and Astronomy · #Dark Matter and Cosmic Phenomena #FOS: Physical sciences #High Energy Physics - Phenomenology (hep-ph) #Neutrino Physics Research #Particle physics theoretical and experimental studies
paper · pdf · doi:10.48550/arxiv.2312.11165
openalex publication_date 2023/12/18 · openalex created_date 2023/12/20 · openalex updated_date 2026/07/28
We discuss the potential of using long-lived particle (LLP) searches for right-handed neutrinos (RHNs) to test resonant leptogenesis and the seesaw mechanism. This is challenging if only RHNs are added to the Standard Model (SM), as naturally the active-sterile mixing strengths |Vℓ N|2 are small, for 1 GeV \lesssim MN \lesssim 1000 GeV. Instead, we consider the minimal B-L gauge model, where a Z^′ gauge boson couples to fermions including the RHNs. During leptogenesis, this gauge coupling introduces scattering processes that washout the B-L asymmetry. At colliders, it can lead to abundant production of RHNs which allows probing the associated seesaw mechanism using LLP searches. We find that LLP searches at the FCC-hh can test leptogenesis and the seesaw mechanism simultaneously, and probe the active-sterile mixing at or below the seesaw floor.