The LEGEND experiment, now under construction, will operate a large array of Ge detectors for the search of neutrinoless double-beta decay of 76Ge. In this paper we report on the process development for the hydrogen reduction of germanium dioxide enriched in 76Ge as part of the effort to manufacture detectors for the LEGEND experiment. The process was optimized via a kinetic un-reacted shrinking model and tested with a batch of natural GeO2. We completed the reduction of a batch of 23 kg isotopically enriched Ge with an average yield of 99.85%. Subsequently, the Ge was purified to intrinsic purity by zone-refining and an overall Ge yield of 99.05% was achieved. Using an intermediate underground storage, an average cosmogenic exposure of 156 h was accumulated. Special care was taken to avoid and recycle losses during the process.
@article{arxiv.2009.07585,
title = {Hydrogen reduction of enriched germanium dioxide and zone-refining for the LEGEND experiment},
author = {Kevin-Peter Gradwohl and Oskar Moras and Jozsef Janicskó-Csáthy and Stefan Schönert and R. Radhakrishnan Sumathi},
journal= {arXiv preprint arXiv:2009.07585},
year = {2021}
}