PNNL

Abstract

The Majorana Demonstrator is a neutrinoless double-beta decay (0) search in the 76Ge isotope that is staged at the 4850-foot level of the Sanford Underground Research Facility (SURF) in Lead, SD. The experiment consists of 58 germanium detectors housed in a low background shield and regularly takes one calibration per week by deploying a 228Th line source for 1 to 2 hours. A suite of analysis tools have been developed in order to automate the process of energy scale calibration for the detector array. In this paper, we will describe the offline procedure for calibration of the Demonstrator germanium detectors, including the simultaneous fitting of multiple spectral peaks, estimation of energy scale uncertainties, the database used for parameter storage and access, and the automation of the calibration procedure.