# Three-cluster dynamics within the *ab initio* no-core shell model with continuum: How many-body correlations and $\alpha $ clustering shape ${}^{6}\mathrm{He}$ [Three-Cluster Dynamics Within The Ab Initio No-Core Shell Model With Continuum: How Many-Body Correlations And Alpha-Clustering Shape 6He]

## Abstract

We realize the treatment of bound and continuum nuclear systems in the proximity of a three-body breakup threshold within the ab initio framework of the no-core shell model with continuum. Many-body eigenstates obtained from the diagonalization of the Hamiltonian within the harmonic-oscillator expansion of the no-core shell model are coupled with continuous microscopic three-cluster states to correctly describe the nuclear wave function both in the interior and asymptotic regions. We discuss the formalism in detail and give algebraic expressions for the case of core + n + n systems. Using similarity-renormalization-group evolved nucleon-nucleon interactions, we analyze the role of ^{4}He + n + n clustering and many-body correlations in the ground and low-lying continuum states of the Borromean ^{6}He nucleus, and study the dependence of the energy spectrum on the resolution scale of the interaction. We show that ^{6}He small binding energy and extended radii compatible with experiment can be obtained simultaneously, without resorting to extrapolations. Here, we also find that a significant portion of the ground-state energy and the narrow width of the first 2 ^{+} resonance stem from many-body correlations that can be interpreted as core-excitation effects.

- Authors:

- Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
- TRIUMF, Vancouver, BC (Canada)
- Alternative Energies and Atomic Energy Commission (CEA), Arpajon (France). DAM

- Publication Date:

- Research Org.:
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Oak Ridge Leadership Computing Facility (OLCF); Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

- Sponsoring Org.:
- USDOE Office of Science (SC); USDOE National Nuclear Security Administration (NNSA)

- OSTI Identifier:
- 1512595

- Alternate Identifier(s):
- OSTI ID: 1430565

- Report Number(s):
- LLNL-JRNL-739751

Journal ID: ISSN 2469-9985; PRVCAN; 893623

- Grant/Contract Number:
- AC52-07NA27344; SCW1158; SCW0498

- Resource Type:
- Accepted Manuscript

- Journal Name:
- Physical Review C

- Additional Journal Information:
- Journal Volume: 97; Journal Issue: 3; Journal ID: ISSN 2469-9985

- Publisher:
- American Physical Society (APS)

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 73 NUCLEAR PHYSICS AND RADIATION PHYSICS

### Citation Formats

```
Quaglioni, Sofia, Romero-Redondo, Carolina, Navrátil, Petr, and Hupin, Guillaume. Three-cluster dynamics within the ab initio no-core shell model with continuum: How many-body correlations and α clustering shape He6 [Three-Cluster Dynamics Within The Ab Initio No-Core Shell Model With Continuum: How Many-Body Correlations And Alpha-Clustering Shape 6He]. United States: N. p., 2018.
Web. doi:10.1103/PhysRevC.97.034332.
```

```
Quaglioni, Sofia, Romero-Redondo, Carolina, Navrátil, Petr, & Hupin, Guillaume. Three-cluster dynamics within the ab initio no-core shell model with continuum: How many-body correlations and α clustering shape He6 [Three-Cluster Dynamics Within The Ab Initio No-Core Shell Model With Continuum: How Many-Body Correlations And Alpha-Clustering Shape 6He]. United States. doi:10.1103/PhysRevC.97.034332.
```

```
Quaglioni, Sofia, Romero-Redondo, Carolina, Navrátil, Petr, and Hupin, Guillaume. Fri .
"Three-cluster dynamics within the ab initio no-core shell model with continuum: How many-body correlations and α clustering shape He6 [Three-Cluster Dynamics Within The Ab Initio No-Core Shell Model With Continuum: How Many-Body Correlations And Alpha-Clustering Shape 6He]". United States. doi:10.1103/PhysRevC.97.034332. https://www.osti.gov/servlets/purl/1512595.
```

```
@article{osti_1512595,
```

title = {Three-cluster dynamics within the ab initio no-core shell model with continuum: How many-body correlations and α clustering shape He6 [Three-Cluster Dynamics Within The Ab Initio No-Core Shell Model With Continuum: How Many-Body Correlations And Alpha-Clustering Shape 6He]},

author = {Quaglioni, Sofia and Romero-Redondo, Carolina and Navrátil, Petr and Hupin, Guillaume},

abstractNote = {We realize the treatment of bound and continuum nuclear systems in the proximity of a three-body breakup threshold within the ab initio framework of the no-core shell model with continuum. Many-body eigenstates obtained from the diagonalization of the Hamiltonian within the harmonic-oscillator expansion of the no-core shell model are coupled with continuous microscopic three-cluster states to correctly describe the nuclear wave function both in the interior and asymptotic regions. We discuss the formalism in detail and give algebraic expressions for the case of core + n + n systems. Using similarity-renormalization-group evolved nucleon-nucleon interactions, we analyze the role of 4He + n + n clustering and many-body correlations in the ground and low-lying continuum states of the Borromean 6He nucleus, and study the dependence of the energy spectrum on the resolution scale of the interaction. We show that 6He small binding energy and extended radii compatible with experiment can be obtained simultaneously, without resorting to extrapolations. Here, we also find that a significant portion of the ground-state energy and the narrow width of the first 2+ resonance stem from many-body correlations that can be interpreted as core-excitation effects.},

doi = {10.1103/PhysRevC.97.034332},

journal = {Physical Review C},

number = 3,

volume = 97,

place = {United States},

year = {2018},

month = {3}

}

*Citation information provided by*

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Web of Science

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