Highly sensitive gamma-spectrometers of GERDA for material screening: Part I

TL;DR

This paper discusses the development and evaluation of highly sensitive gamma-spectrometers used for material screening in the GERDA experiment, aiming to detect ultra-low radioactive contamination for neutrinoless double beta-decay searches.

Contribution

It provides an overview of gamma-spectrometry laboratories and compares their evaluation accuracy, enhancing material screening capabilities for rare event experiments.

Findings

Intercomparison shows varying evaluation accuracy among laboratories.

High-sensitivity gamma-spectrometers are essential for ultra-low background detection.

The study improves reliability in material screening for GERDA.

Abstract

The GERDA experiment aims to search for the neutrinoless double beta-decay of 76Ge and possibly for other rare processes. The sensitivity of the first phase is envisioned to be more than one order of magnitude better than in previous neutrinoless double beta-decay experiments. This implies that materials with ultra-low radioactive contamination need to be used for the construction of the detector and its shielding. Therefore the requirements on material screening include high-sensitivity low-background detection techniques and long measurement times. In this article, an overview of material-screening laboratories available to the GERDA collaboration is given, with emphasis on the gamma-spectrometry. Additionally, results of an intercomparison of the evaluation accuracy in these laboratories are presented.