The Majorana Neutrinoless Double-Beta Decay Experiment

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.Comment: 10 pages, 7 figure

Thermostabilization System Based on Two-phase Closed Cryogenic Thermosyphon for RED100 Detector

AbstractThe RED 100 emission detector requires thermostabilization at about 100K. The heat transfer characteristics of a two-phase closed cryogenic thermosyphon made of copper pipe and bellow flex hoses with nitrogen fluid have been investigated. The thermosyphon consists of sealed pipe enclosed in a vacuum jacket and uses a free-boiling liquid nitrogen pool as a cooling machine. The system is very flexible and can provide heat transfer rate up to 100W in the temperature range of 80-100K