The Majorana Neutrinoless Double-Beta Decay Experiment

TL;DR

The Majorana experiment aims to detect neutrinoless double-beta decay using enriched germanium detectors, with advanced background reduction techniques, to reach a sensitivity capable of probing effective neutrino masses around 0.03-0.04 eV over a decade.

Contribution

This paper presents a detailed design and sensitivity prediction for a large-scale germanium detector array targeting neutrinoless double-beta decay detection.

Findings

Predicted half-life sensitivity of ~4x10^27 years for 10 years of operation.

Effective Majorana neutrino mass sensitivity of ~0.03-0.04 eV.

Background reduction strategies significantly improve detection prospects.

Abstract

The proposed Majorana double-beta decay experiment is based on an array of segmented intrinsic Ge detectors with a total mass of 500 kg of Ge isotopically enriched to 86% in 76Ge. A discussion is given of background reduction by: material selection, detector segmentation, pulse shape analysis, and electro-formation of copper parts and granularity. Predictions of the experimental sensitivity are given. For an experimental running time of 10 years over the construction and operation of Majorana, a half-life sensitivity of ~4x10^27 y (neutrinoless) is predicted. This corresponds to an effective Majorana mass of the electron neutrino of ~0.03-0.04 eV, according to recent QRPA and RQRPA matrix element calculations.