Showing papers by "V. M. Gehman published in 2008"
Los Alamos National Laboratory1, Pacific Northwest National Laboratory2, University of North Carolina at Chapel Hill3, Lawrence Berkeley National Laboratory4, University of Washington5, University of South Carolina6, North Carolina State University7, University of Chicago8, Oak Ridge National Laboratory9, Joint Institute for Nuclear Research10, University of Tennessee11, Osaka University12, Duke University13, University of Alberta14, Black Hills State University15, University of South Dakota16, Queen's University17
TL;DR: The MAJORANA Collaboration as mentioned in this paper uses the well-established technique of searching for neutrinoless double-beta decay in high purity Ge-diode radiation detectors that play both roles of source and detector.
Abstract: Neutrinoless double-beta decay searches play a major role in determining the nature of neutrinos, the existence of a lepton violating process, and the effective Majorana neutrino mass. The MAJORANA Collaboration proposes to assemble an array of HPGe detectors to search for neutrinoless double-beta decay in 76Ge. Our proposed method uses the well-established technique of searching for neutrinoless double-beta decay in high purity Ge-diode radiation detectors that play both roles of source and detector. The technique is augmented with recent improvements in signal processing and detector design, and advances in controlling intrinsic and external backgrounds. Initially, MAJORANA aims to construct a prototype module containing 60 kg of Ge detectors to demonstrate the potential of a future 1-tonne experiment. The design and potential reach of this prototype Demonstrator module will be presented. This paper will also discuss detector optimization and low-background requirements, such as material purity, background rejection, and identification of rare backgrounds required to reach the sensitivity goals of the MAJORANA experiment.
19 citations
Czech Technical University in Prague1, National Institute of Radiological Sciences2, Osaka University3, University of Washington4, Los Alamos National Laboratory5, University of North Carolina at Chapel Hill6, Charles University in Prague7, University of Tokushima8, International Christian University9, Hiroshima University10, Joint Institute for Nuclear Research11, Tohoku University12
TL;DR: The MOON detector as discussed by the authors is a super ensemble of multi-layer modules, each being composed by PL scintillator plates and position-sensitive detector planes with good overall energy resolution of σ ≈ 2% at the Q ≥ 3 MeV.
Abstract: The MOON (Majorana/Mo Observatory Of Neutrinos) project aims at studies of the Majorana nature of the neutrino (ν) and the ν-mass spectrum by spectroscopic experiments of neutrino-less double beta decays (0νββ) with the ν-mass sensitivity of 〈m
〉 = 100−30 meV. The solid scintillator option of the MOON detector is a super ensemble of multi-layer modules, each being composed by PL scintillator plates and position-sensitive detector planes with good overall energy resolution of σ ≈ 2% at the Q
ββ
≈ 3 MeV. Thin ββ source films are interleaved between the detector planes. High localization of the two β tracks enables one to select true signals and reject BG ones. The multi-layer structure of the detector makes it realistic to build a compact ton-scale detector. MOON with detector ≠ ββ source is used for studying 0νββ decays from 100Mo, 82Se and other ββ isotopes with large Q
ββ
. Real-time exclusive measurements of low energy solar neutrinos can be made by observing inverse β rays from solar-ν captures of 100Mo in delayed coincidence with the subsequent β decay of 100Tc.
18 citations
Posted Content•
TL;DR: MaGe as mentioned in this paper is a Monte Carlo framework for low-energy and low-background radiation detectors based on the Geant4 simulation toolkit, specifically for the Majorana and Gerda double-beta decay experiments.
Abstract: A Monte Carlo framework, MaGe, has been developed based on the Geant4 simulation toolkit. Its purpose is to simulate physics processes in low-energy and low-background radiation detectors, specifically for the Majorana and Gerda $^{76}$Ge neutrinoless double-beta decay experiments. This jointly-developed tool is also used to verify the simulation of physics processes relevant to other low-background experiments in Geant4. The MaGe framework contains simulations of prototype experiments and test stands, and is easily extended to incorporate new geometries and configurations while still using the same verified physics processes, tunings, and code framework. This reduces duplication of efforts and improves the robustness of and confidence in the simulation output.
7 citations
01 Nov 2008
TL;DR: The Majorana Experiment as discussed by the authors used arrays of enriched HPGe detectors to search for the neutrinoless double-beta decay of 76Ge and confirmed the Majorana nature of the neutrino.
Abstract: The Majorana Experiment will use arrays of enriched HPGe detectors to search for the neutrinoless double-beta decay of 76Ge. Such a decay, if found, would show lepton-number violation, confirm the Majorana nature of the neutrino, and help determine the effective Majorana neutrino mass. A potentially important background contribution to this and other double-beta decay experiments arises from decays of alpha-emitting isotopes in the 232Th and 238U decay chains on and near the surfaces of the detectors. An alpha particle emitted from the surface can lose energy within the dead region of a detector, depositing only a partial amount of its kinetic energy within the active region and possibly mimicking the energy signal from neutrinoless double-beta decay. Cleanliness, exposure to radon, detector design, and analysis techniques all contribute to the effect from surface alphas. Our experimental and simulation efforts to understand and mitigate surface alpha backgrounds for both n-type and p-type HPGe detectors will be presented.
1 citations