Departmental Colloquium - Big Detectors, Rare Signals: Probing Majorana Neutrinos with Xenon Experiments

Erica Caden,

Research Scientist | SNOLAB

Adjunct Faculty | Laurentian McGill

Abstract

Neutrinoless double beta decay (0νββ) is a hypothetical nuclear process whose observation would have profound implications for particle physics, establishing the Majorana nature of neutrinos and providing direct evidence of lepton number violation. Among candidate isotopes, xenon-136, has emerged as one of the most promising due to its scalability, radiopurity, and versatility in detector design. Recent results from xenon experiments including have significantly improved half-life limits, pushing sensitivities beyond 10^26 years. In parallel, large-scale liquid xenon detectors developed for dark matter searches are increasingly being explored for their sensitivity to double beta decay. Although not optimized for this channel, their ultra-low backgrounds and large target masses provide a powerful complementary approach. Looking ahead, proposed next-generation instruments such as XLZD aim to perform dark matter and rare event searches at unprecedented scales. With significantly increased exposure and improved background control, such detectors could extend sensitivity to 0νββ well into unexplored parameter space. This talk will discuss the physics motivation, experimental challenges, and technological innovations driving the field, as well as the growing synergy between dark matter and double beta decay efforts. The continued progress of xenon-based searches positions them at the forefront of efforts to determine whether neutrinos are their own antiparticles and to probe physics beyond the Standard Model.

Timbits, coffee, tea will be served in STI A before the colloquium.