# First Results from the AMoRE-Pilot neutrinoless double beta decay experiment

## TL;DR

The AMoRE-Pilot experiment searches for neutrinoless double beta decay of $^{100}$Mo using cryogenic detectors and sets new limits on the decay half-life and neutrino mass, demonstrating the feasibility of this detection approach.

## Contribution

First results from the AMoRE-Pilot experiment using cryogenic detectors with dual heat and light readout for neutrinoless double beta decay search.

## Key findings

- No evidence for $0
uetaeta$ decay was observed.
- Set a lower half-life limit of $9.5 imes 10^{22}$ years at 90% C.L.
- Established an effective Majorana neutrino mass limit of 1.2-2.1 eV.

## Abstract

The Advanced Molybdenum-based Rare process Experiment (AMoRE) aims to search for neutrinoless double beta decay (0$\nu\beta\beta$) of $^{100}$Mo with $\sim$100 kg of $^{100}$Mo-enriched molybdenum embedded in cryogenic detectors with a dual heat and light readout. At the current, pilot stage of the AMoRE project we employ six calcium molybdate crystals with a total mass of 1.9 kg, produced from $^{48}$Ca-depleted calcium and $^{100}$Mo-enriched molybdenum ($^{48\textrm{depl}}$Ca$^{100}$MoO$_4$). The simultaneous detection of heat(phonon) and scintillation (photon) signals is realized with high resolution metallic magnetic calorimeter sensors that operate at milli-Kelvin temperatures. This stage of the project is carried out in the Yangyang underground laboratory at a depth of 700 m. We report first results from the AMoRE-Pilot $0\nu\beta\beta$ search with a 111 kg$\cdot$d live exposure of $^{48\textrm{depl}}$Ca$^{100}$MoO$_4$ crystals. No evidence for $0\nu\beta\beta$ decay of $^{100}$Mo is found, and a upper limit is set for the half-life of 0$\nu\beta\beta$ of $^{100}$Mo of $T^{0\nu}_{1/2} > 9.5\times10^{22}$ y at 90% C.L.. This limit corresponds to an effective Majorana neutrino mass limit in the range $\langle m_{\beta\beta}\rangle\le(1.2-2.1)$ eV.