English
Related papers

Related papers: Open-Shell Nuclei from No-Core Shell Model with Pe…

200 papers

We merge two successful ab initio nuclear-structure methods, the no-core shell model (NCSM) and the multi-reference in-medium similarity renormalization group (IM-SRG) to define a new many-body approach for the comprehensive description of…

Nuclear Theory · Physics 2017-04-20 Eskendr Gebrerufael , Klaus Vobig , Heiko Hergert , Robert Roth

We present an overview of recent results and developments of the no-core shell model (NCSM), an ab initio approach to the nuclear many-body problem for light nuclei. In this approach, we start from realistic two-nucleon or two- plus…

Nuclear Theory · Physics 2009-06-19 Petr Navratil , Sofia Quaglioni , Ionel Stetcu , Bruce R. Barrett

We present a new approach to the construction of effective interactions suitable for many-body calculations by means of the no-core shell model (NCSM). We consider an effective field theory (EFT) with only nucleon fields directly in the…

Nuclear Theory · Physics 2008-11-26 I. Stetcu , B. R. Barrett , U. van Kolck

A symplectic no-core shell model (Sp-NCSM) is constructed with the goal of extending the {\it ab-initio} NCSM to include strongly deformed higher-oscillator-shell configurations and to reach heavier nuclei that cannot be studied currently…

No-Core Gamow Shell Model (NCGSM) is applied for the first time to study selected well-bound and unbound states of helium isotopes. This model is formulated on the complex energy plane and, by using a complete Berggren ensemble, treats…

Nuclear Theory · Physics 2015-06-12 G. Papadimitriou , J. Rotureau , N. Michel , M. Płoszajczak , B. R. Barrett

We investigate the order-by-order convergence behavior of many-body perturbation theory (MBPT) as a simple and efficient tool to approximate the ground-state energy of closed-shell nuclei. To address the convergence properties directly, we…

Nuclear Theory · Physics 2016-04-20 Alexander Tichai , Joachim Langhammer , Sven Binder , Robert Roth

This contribution reviews a number of applications of the ab initio no-core shell model (NCSM) within nuclear physics and beyond. We will highlight a nuclear-structure study of the A = 12 isobar using a chiral NN + 3NF interaction. In the…

Nuclear Theory · Physics 2009-05-04 C. Forssen , J. Christensson , P. Navratil , S. Quaglioni , S. Reimann , J. Vary , S. Aberg

There has been significant recent progress in solving the long-standing problems of how nuclear shell structure and collective motion emerge from underlying microscopic inter-nucleon interactions. We review a selection of recent significant…

A novel Rayleigh-Schr\"odinger many-body perturbation theory (MBPT) approach is introduced by making use of a particle-number-breaking Bogoliubov reference state to tackle (near-)degenerate open-shell fermionic systems. By choosing a…

Nuclear Theory · Physics 2018-10-17 Alexander Tichai , Pierre Arthuis , Thomas Duguet , Heiko Hergert , Vittorio Somá , Robert Roth

Fully-microscopic No-core Shell Model (NCSM) calculations of all stable $s$ and $p$ shell nuclei are used to determine realistic $NN$ interaction JISP16 describing not only the two-nucleon data but the binding energies and spectra of nuclei…

Nuclear Theory · Physics 2015-06-26 A. M. Shirokov , J. P. Vary , A. I. Mazur , T. A. Weber

A microscopic description of nuclei is important to understand the nuclear shell-model from fundamental principles. This is difficult to achieve for more than the lightest nuclei without an effective approximation scheme. The purpose of…

Nuclear Theory · Physics 2013-08-19 Gustav R. Jansen

No-core shell model (NCSM) calculations using ab initio effective interactions are very successful in reproducing experimental nuclear spectra. The main theoretical approach is the use of effective operators, which include correlations left…

Nuclear Theory · Physics 2007-05-23 Bruce R. Barrett , Ionel Stetcu , Petr Navratil , James P. Vary

The neon isotopic chain displays a rich phenomenology, ranging from clustering in the ground-state of the self-conjugate doubly open-shell stable $^{20}$Ne isotope to the physics of the island of inversion around the neutron-rich $^{30}$Ne…

Nuclear many-body calculations are computationally demanding. An estimate of their accuracy is often hampered by the limited amount of computational resources even on present-day supercomputers. We provide an extrapolation method based on…

Nuclear Theory · Physics 2009-11-10 H. Zhan , A. Nogga , B. R. Barrett , J. P. Vary , P. Navratil

The no-core shell model (NCSM) is an \textit{ab initio} method that solves the nuclear many-body problem by expanding the many-particle wave function into a (typically) harmonic oscillator basis and minimizing the energy to obtain the…

Nuclear Theory · Physics 2024-02-06 Konstantinos Kravvaris , Sofia Quaglioni , Petr Navratil

In spite of missing dynamical correlations, the projected generator coordinate method (PGCM) was recently shown to be a suitable method to tackle the low-lying spectroscopy of complex nuclei. Still, describing absolute binding energies and…

Perturbative and non-perturbative expansion methods already constitute a tool of choice to perform ab initio calculations over a significant part of the nuclear chart. In this context, the categories of accessible nuclei directly reflect…

Nuclear Theory · Physics 2022-01-28 Mikael Frosini , Thomas Duguet , Jean-Paul Ebran , Vittorio Somà

An exact relation which links the ideal model space to be used in A-body calculations when the two-body interaction is given in a truncated model space is derived. Its implications on the effective field theory (EFT) approach to…

Nuclear Theory · Physics 2018-01-01 C. -J. Yang

The ab initio no-core shell model (NCSM) is extended to include a realistic three-body interaction in calculations for p-shell nuclei. The NCSM formalism is reviewed and new features needed in calculations with three-body forces are…

Nuclear Theory · Physics 2009-11-10 P. Navratil , W. E. Ormand

An ensemble of neural networks is employed to extrapolate no-core shell model (NCSM) results to infinite model space for light nuclei. We present a review of our neural network extrapolations of the NCSM results obtained with the Daejeon16…

Nuclear Theory · Physics 2025-12-22 Aleksandr Mazur , Roman Sharypov , Andrey Shirokov
‹ Prev 1 2 3 10 Next ›