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Title: Calculating beta decay in the deformed self-consistent quasiparticle random phase approximation

Abstract

We discuss a recent global calculation of beta-decay rates in the self-consistent Skyrme quasiparticle random phase approximation (QRPA), with axially symmetric nuclear deformation treated explicitly. The calculation makes makes use of the finite-amplitude method, first proposed by Nakatsukasa and collaborators, to reduce computation time. The results are comparable in quality to those of several other global QRPA calculations. The QRPA may have reached the limit of its accuracy.

Authors:
 [1];  [1];  [2]
  1. Department of Physics and Astronomy, University of North Carolina, Chapel Hill, NC 27599-3255 (United States)
  2. (United States)
Publication Date:
OSTI Identifier:
22609083
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 1743; Journal Issue: 1; Conference: CETUP 2015: Workshop on dark matter, neutrino physics and astrophysics, Deadwood, SD (United States), 15 Jun - 17 Jul 2015, PPC 2015: 9. international conference on interconnections between particle physics and cosmology, Deadwood, SD (United States), 15 Jun - 17 Jul 2015; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS; ACCURACY; AMPLITUDES; AXIAL SYMMETRY; BETA DECAY; COMPARATIVE EVALUATIONS; COMPUTERIZED SIMULATION; NUCLEAR DEFORMATION; QUASI PARTICLES; RANDOM PHASE APPROXIMATION; RANDOMNESS; SKYRME POTENTIAL

Citation Formats

Engel, Jonathan, E-mail: engelj@physics.unc.edu, Mustonen, M. T., E-mail: mika.mustonen@yale.edu, and Center for Theoretical Physics, Sloane Physics Laboratory, Yale University, New Haven, CT 06052. Calculating beta decay in the deformed self-consistent quasiparticle random phase approximation. United States: N. p., 2016. Web. doi:10.1063/1.4953297.
Engel, Jonathan, E-mail: engelj@physics.unc.edu, Mustonen, M. T., E-mail: mika.mustonen@yale.edu, & Center for Theoretical Physics, Sloane Physics Laboratory, Yale University, New Haven, CT 06052. Calculating beta decay in the deformed self-consistent quasiparticle random phase approximation. United States. doi:10.1063/1.4953297.
Engel, Jonathan, E-mail: engelj@physics.unc.edu, Mustonen, M. T., E-mail: mika.mustonen@yale.edu, and Center for Theoretical Physics, Sloane Physics Laboratory, Yale University, New Haven, CT 06052. 2016. "Calculating beta decay in the deformed self-consistent quasiparticle random phase approximation". United States. doi:10.1063/1.4953297.
@article{osti_22609083,
title = {Calculating beta decay in the deformed self-consistent quasiparticle random phase approximation},
author = {Engel, Jonathan, E-mail: engelj@physics.unc.edu and Mustonen, M. T., E-mail: mika.mustonen@yale.edu and Center for Theoretical Physics, Sloane Physics Laboratory, Yale University, New Haven, CT 06052},
abstractNote = {We discuss a recent global calculation of beta-decay rates in the self-consistent Skyrme quasiparticle random phase approximation (QRPA), with axially symmetric nuclear deformation treated explicitly. The calculation makes makes use of the finite-amplitude method, first proposed by Nakatsukasa and collaborators, to reduce computation time. The results are comparable in quality to those of several other global QRPA calculations. The QRPA may have reached the limit of its accuracy.},
doi = {10.1063/1.4953297},
journal = {AIP Conference Proceedings},
number = 1,
volume = 1743,
place = {United States},
year = 2016,
month = 6
}
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  • In this paper a microscopic approach to calculation of the nuclear matrix element M{sup 0{nu}} for neutrinoless double-{beta} decay with an account for nuclear deformation is presented in length and applied for {sup 76}Ge, {sup 150}Nd, and {sup 160}Gd. The proton-neutron quasiparticle random-phase approximation with a realistic residual interaction (the Brueckner G matrix derived from the charge-depending Bonn nucleon-nucleon potential) is used as the underlying nuclear structure model. The effects of the short-range correlations and the quenching of the axial vector coupling constant g{sub A} are analyzed. The results suggest that neutrinoless double-{beta} decay of {sup 150}Nd, to be measuredmore » soon by the SNO+ Collaboration, may provide one of the best probes of the Majorana neutrino mass. This confirms our preliminary conclusion in Fang et al. [Phys. Rev. C 82, 051301(R) (2010)].« less