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Title: Solving The Long-Standing Problem Of Nuclear Reactions At The Highest Microscopic Level: Annual Continuation And Progress Report

The aim of this project is to develop a comprehensive framework that will lead to a fundamental description of both structural properties and reactions of light nuclei in terms of constituent protons and neutrons interacting through nucleon-nucleon (NN) and three-­nucleon (NNN) forces. This project will provide the research community with the theoretical and computational tools that will enable: (1) an accurate prediction for fusion reactions that power stars and Earth-­based fusion facilities; (2) an improved description of the spectroscopy of exotic nuclei, including light Borromean systems; and (3) a fundamental understanding of the three-­nucleon force in nuclear reactions and nuclei at the drip line. To achieve this goal, we build upon a promising technique emerged recently as a candidate to reach a fundamental description of low-­energy binary reactions between light ions, that is the ab initio no-­core shell model combined with the resonating-­group method (NCSM/RGM). This approach has demonstrated the capability to describe binary reactions below the three-­body breakup threshold based, up to now, on similarity-­renormalization-­group (SRG) 5 evolved NN only potentials. To advance the understanding of nuclear reactions at low energies and light exotic nuclei, this project aims at extending the NCSM/RGM approach to include the full range ofmore » NNN interactions as well as the treatment of three-­cluster bound and continuum states. Three-­nucleon interactions are unavoidable components of a fundamental nuclear Hamiltonian obtained in a low-­energy effective theory. In addition, three-­nucleon force terms are induced by the SRG procedure and have to be taken into account for such a transformation to be unitary in many-­body calculations. At the same time, the introduction of three-­body cluster states is key to achieve a microscopic description of Borromean systems as well as three-­body breakup reactions. This project will both enhance the fundamentality and enlarge the scope of our microscopic description of nuclear properties. A successful completion of this project will result in improved accuracy of the 3He( 3He,2p) 4He and 3He(α,γ) 7Be reaction rates and consequently, in enhancement of the predictive capability of the standard solar model. In addition, we will study also the mirror reactions 3H( 3H,2n) 4He and 3H(α,γ) 7Li (a key reaction for the production of 7Li in the standard big-­bang nucleosynthesis), and the spectroscopy of the 6He, 6Be, and 11Li nuclei.« less
Authors:
 [1]
  1. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Publication Date:
OSTI Identifier:
1124871
Report Number(s):
LLNL-TR-651616
DOE Contract Number:
W-7405-ENG-48; AC52-07NA27344
Resource Type:
Technical Report
Research Org:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org:
USDOE
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS