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Related papers: Multistep shell model in the complex energy plane

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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

The nuclear shell model is one of the prime many-body methods to study the structure of atomic nuclei, but it is hampered by an exponential scaling on the basis size as the number of particles increases. We present a shell-model quantum…

Quantum Physics · Physics 2023-09-18 A. Pérez-Obiol , A. M. Romero , J. Menéndez , A. Rios , A. García-Sáez , B. Juliá-Díaz

A simple approximation to shell model is proposed in which the low energy excitation spectra corresponds to the identical nucleons occupying the same single particle states where they preferred to form pairs for the ground states. We call…

Nuclear Theory · Physics 2008-10-08 S. Haq , Y. Sadeq , I. M. Hamammu

A generalization of the Complex Shell Model formalism is presented which includes antibound states in the basis. These states, together with bound states, Gamow states, and the continuum background, represented by properly chosen scattering…

Nuclear Theory · Physics 2007-05-23 R. Id Betan , R. J. Liotta , N. Sandulescu , T. Vertse , R. Wyss

A technique for describing scattering states within the nuclear shell model is proposed. This technique is applied to scattering of nucleons by $\alpha$ particles based on ab initio No-Core Shell Model calculations of $^5$He and $^5$Li…

Nuclear Theory · Physics 2016-04-19 I. A. Mazur , A. M. Shirokov , A. I. Mazur , J. P. Vary

The nucleus is a correlated open quantum many-body system. The presence of states that are unbound to particle emission may have significant impact on spectroscopic properties of nuclei, especially those close to the particle drip lines. In…

Nuclear Theory · Physics 2007-05-23 N. Michel , W. Nazarewicz , M. Ploszajczak , J. Rotureau

We perform realistic shell-model calculations for nuclei with valence nucleons outside 48Ca, employing two different model spaces. The matrix elements of the effective two-body interaction and electromagnetic multipole operators have been…

Nuclear Theory · Physics 2014-03-24 L. Coraggio , A. Covello , A. Gargano , N. Itaco

We present an extension of the Hamiltonian of the two dimensional limit of the vibron model encompassing all possible interactions up to four-body operators. We apply this Hamiltonian to the modeling of the experimental bending spectrum of…

Chemical Physics · Physics 2021-03-17 Jamil Khalouf-Rivera , Francisco Pérez-Bernal , Miguel Carvajal

A one-dimensional harmonic oscillator in a box is used to introduce the oblique-basis concept. The method is extended to the nuclear shell model by combining traditional spherical states, which yield a diagonal representation of the usual…

Nuclear Theory · Physics 2009-11-07 V. G. Gueorguiev , J. P. Draayer

We present a simple time dependent model for the excitation of a nucleon from a bound state to a continuum resonant state in a neutron-core complex potential which acts as a final state interaction. The final state is described by an…

Nuclear Theory · Physics 2008-11-26 G. Blanchon , A. Bonaccorso , D. M. Brink , A. García-Camacho , N. Vinh Mau

A nuclear structure model based on linear response theory (i.e., Random Phase Approximation) and which includes pairing correlations and anharmonicities (coupling with collective vibrations), has been implemented in such a way that it can…

Nuclear Theory · Physics 2009-11-10 D. Sarchi , P. F. Bortignon , G. Colo`

We investigate the hypernuclear cluster states of $_\Lambda^{12}\mathrm{B}$ using a neural-network-driven microscopic model. We extend the Control Neural Networks (Ctrl.NN) method and systematically calculate the positive-parity spectrum of…

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

A model of multicellular systems with several types of cells is developed from the phase field model. The model is presented as a set of partial differential equations of the field variables, each of which expresses the shape of one cell.…

Biological Physics · Physics 2015-05-30 Makiko Nonomura

An effective two-body interaction is constructed from a new Reid-like $NN$ potential for a large no-core space consisting of six major shells and is used to generate the shell-model properties for light nuclei from $A$=2 to 6. (For…

Nuclear Theory · Physics 2008-11-26 D. C. Zheng , J. P. Vary , B. R. Barrett

The one-dimensional harmonic oscillator in a box problem is used to introduce the concept of a mixed-mode shell-model scheme. The method combines low-lying ``pure mode'' states of a system to achieve a better description in situations where…

Nuclear Theory · Physics 2007-05-23 V. G. Gueorguiev , J. P. Draayer

The nuclear many-body problem at the limits of stability is considered in the framework of the Continuum Shell Model that allows a unified description of intrinsic structure and reactions. Technical details behind the method are highlighted…

Nuclear Theory · Physics 2017-08-23 Alexander Volya

A realistic description of halo nuclei, characterized by low-lying breakup thresholds, requires a proper treatment of continuum effects. We have developed an ab initio approach, the no-core shell model with continuum (NCSMC), capable of…

Nuclear Theory · Physics 2026-05-26 Petr Navratil , Sofia Quaglioni , Guillaume Hupin , Michael Gennari , Kostas Kravvaris

The inelasticity in nucleus-nucleus collisions at high energies is calculated in the framework of geometrical multichain model. The very fast increase of the inelasticity is found as a result of a second-stage cascading process. The same…

High Energy Physics - Phenomenology · Physics 2008-11-26 Tadeusz Wibig

We develop a theoretical approach for the dynamics of Rydberg excitations in ultracold gases, with a realistically large number of atoms. We rely on the reduction of the single-atom Bloch equations to rate equations, which is possible under…

Atomic Physics · Physics 2009-11-13 Cenap Ates , Thomas Pohl , Thomas Pattard , Jan M. Rost