New Symmetry-Adapted ab initio
Approach to Nuclear Reactions for
Intermediate-mass Nuclei
Alexis Mercenne, Kristina D. Launey, Jutta E. Escher, Tomas Dytrych,
and Jerry P. Draayer
1 Introduction
Ab initio descriptions of reactions of nuclei heavier than 16 O remain a challenge in
nuclear physics. Their theoretical and experimental study is of utmost importance to
identify various quantum mechanisms that can explain the complexity of nuclei. In
addition, many simulations of astrophysical phenomena are very sensitive to nuclear
reaction cross sections. For example, simulations of X-ray burst nucleosynthesis
have been found to be sensitive to several nuclear reaction rates for intermediateand medium-mass nuclei [1], pointing to the need for accurate cross sections. For
theoretical predictions, this level of accuracy can be achieved through an ab initio
description of nuclear reactions. Recent progresses in ab initio nuclear theory using
QCD-inspired realistic interactions along with the continuous improvement of high
performance computing have given the necessary tools to theoretical approaches
such as the no-core shell model (NCSM) to provide an ab initio description of the
structure of light nuclei [2, 3]. Its recent implementation within the RGM [4], the
NCSM/RGM, has allowed a microscopic study of nuclear reactions [5–7], pursuing
the long-standing goal of unifying nuclear structure and reactions. Recently, it has
been demonstrated that the SA-NCSM [8, 9], which employs a physically relevant
A. Mercenne () · K. D. Launey · J. P. Draayer
Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA, USA
e-mail: amercenne1@lsu.edu
J. E. Escher
Lawrence Livermore National Laboratory, Livermore, CA, USA
T. Dytrych
Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA, USA
Nuclear Physics Institute, Academy of Sciences of the Czech Republic, ˇ
Rež, Czech Republic
© This is a U.S. government work and not under copyright protection
in the U.S.; foreign copyright protection may apply 2021
J. Escher et al. (eds.), Compound-Nuclear Reactions, Springer Proceedings in
Physics 254, https://doi.org/10.1007/978-3-030-58082-7_9
73
Approach to Nuclear Reactions for
Intermediate-mass Nuclei
Alexis Mercenne, Kristina D. Launey, Jutta E. Escher, Tomas Dytrych,
and Jerry P. Draayer
1 Introduction
Ab initio descriptions of reactions of nuclei heavier than 16 O remain a challenge in
nuclear physics. Their theoretical and experimental study is of utmost importance to
identify various quantum mechanisms that can explain the complexity of nuclei. In
addition, many simulations of astrophysical phenomena are very sensitive to nuclear
reaction cross sections. For example, simulations of X-ray burst nucleosynthesis
have been found to be sensitive to several nuclear reaction rates for intermediateand medium-mass nuclei [1], pointing to the need for accurate cross sections. For
theoretical predictions, this level of accuracy can be achieved through an ab initio
description of nuclear reactions. Recent progresses in ab initio nuclear theory using
QCD-inspired realistic interactions along with the continuous improvement of high
performance computing have given the necessary tools to theoretical approaches
such as the no-core shell model (NCSM) to provide an ab initio description of the
structure of light nuclei [2, 3]. Its recent implementation within the RGM [4], the
NCSM/RGM, has allowed a microscopic study of nuclear reactions [5–7], pursuing
the long-standing goal of unifying nuclear structure and reactions. Recently, it has
been demonstrated that the SA-NCSM [8, 9], which employs a physically relevant
A. Mercenne () · K. D. Launey · J. P. Draayer
Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA, USA
e-mail: amercenne1@lsu.edu
J. E. Escher
Lawrence Livermore National Laboratory, Livermore, CA, USA
T. Dytrych
Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA, USA
Nuclear Physics Institute, Academy of Sciences of the Czech Republic, ˇ
Rež, Czech Republic
© This is a U.S. government work and not under copyright protection
in the U.S.; foreign copyright protection may apply 2021
J. Escher et al. (eds.), Compound-Nuclear Reactions, Springer Proceedings in
Physics 254, https://doi.org/10.1007/978-3-030-58082-7_9
73