Speaker
Description
The goal of OPOSSUM is to discriminate, for the very first time, Single Site Events (SSE) from Multi Site Events (MSE) in mK calorimeters for rare-event searches. The OPOSSUM project, funded by the European Research Council through a Starting Grant in 2024, embarks on a transformative path to improve by an order of magnitude the sensitivity of neutrinoless double-beta decay (0νββ) experiments — a key process which, if observed, would redefine our understanding of neutrinos and physics beyond the Standard Model. Detecting 0νββ would not only confirm the Majorana nature of neutrinos but could also provide insight into the absolute neutrino mass scale and hierarchy.
At the heart of OPOSSUM is a novel discrimination strategy designed to positively identify 0νββ events (SSE) while rejecting other dominant background sources, such as alpha and gamma interactions (MSE) in TeO₂. Thanks to its natural 33% isotopic abundance, ¹³⁰Te emerges as the leading 0νββ candidate, bypassing the need for the increasingly challenging enrichment process. In OPOSSUM, twelve CUORE prototype crystals will be equipped with six Microwave Kinetic Inductance Detectors (MKIDs), in addition to existing thermistors. Through integrated analysis, the OPOSSUM technique has the potential to reduce the CUORE background to below 10⁻⁴ counts/keV/kg/y, enabling sensitivity to the inverted hierarchy region corresponding to a 10 meV Majorana mass.
In this contribution, I will present the innovative experimental concept of OPOSSUM, discuss its potential, and report on the first steps towards the implementation of MKIDs on TeO₂. Moreover, I will show the first results of superconducting film deposition on TeO₂, a crucial milestone for the development of this technique.
| Position | researcher |
|---|---|
| Affiliation | INFN-LNGS |
| Country | Italy |