The Experts below are selected from a list of 147 Experts worldwide ranked by ideXlab platform
Maria Piarulli - One of the best experts on this subject based on the ideXlab platform.
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atomic nuclei from quantum monte carlo calculations with chiral eft interactions
Frontiers in Physics, 2020Co-Authors: Stefano Gandolfi, Diego Lonardoni, Alessandro Lovato, Maria PiarulliAbstract:Quantum Monte Carlo methods are powerful numerical tools to accurately solve the Schr\"odinger equation for nuclear systems, a necessary step to describe the structure and reactions of nuclei and nucleonic matter starting from realistic interactions and currents. These \textit{ab-initio} methods have been used to accurately compute properties of light nuclei -- including their spectra, moments, and transitions -- and the equation of state of neutron and nuclear matter. In this work we review selected results obtained by combining quantum Monte Carlo methods and recent Hamiltonians constructed within chiral effective field theory.
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atomic nuclei from quantum monte carlo calculations with chiral eft interactions
arXiv: Nuclear Theory, 2020Co-Authors: Stefano Gandolfi, Diego Lonardoni, Alessandro Lovato, Maria PiarulliAbstract:Quantum Monte Carlo methods are powerful numerical tools to accurately solve the Schr\"odinger equation for nuclear systems, a necessary step to describe the structure and reactions of nuclei and nucleonic matter starting from realistic interactions and currents. These ab-initio methods have been used to accurately compute properties of light nuclei -- including their spectra, moments, and transitions -- and the equation of state of neutron and nuclear matter. In this work we review selected results obtained by combining quantum Monte Carlo methods and recent Hamiltonians constructed within chiral effective field theory.
Dario Vretenar - One of the best experts on this subject based on the ideXlab platform.
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localization and clustering in atomic nuclei
Journal of Physics G, 2017Co-Authors: J.-P. Ebran, E Khan, Tamara Niksic, Dario VretenarAbstract:ucleon localization, and formation of clusters in nucleonic matter and finite nuclei are explored in a framework based on nuclear energy density functionals. The liquid–cluster transition is investigated and different measures of localization are discussed. The formation and evolution of α-clusters in excited states of both N = Z and neutron-rich nuclei are analysed. The effects of spin–orbit coupling are discussed in relation to the confining potential.
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how atomic nuclei cluster
arXiv: Nuclear Theory, 2012Co-Authors: J.-P. Ebran, E Khan, Tamara Niksic, Dario VretenarAbstract:The contribution of the depth of the nuclear potential to the localisation of the single-particle wave-function, leading to clusterisation, is investigated using energy density functionnals. In this framework the formation of clusters indicates that nuclei behave like a Fermi liquid close to the liquid to solid transition. An analytical interpretation is provided using the harmonic oscillator approximation. The emergence of various structures in nucleonic matter, such as crystal, clusters, liquid drops and haloes is analysed. Haloes and clusters exhibit opposite features with respect to nucleonic localization.
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How atomic nuclei cluster?
AIP Conference Proceedings, 2012Co-Authors: J.-P. Ebran, T. Nikšić, E Khan, Dario VretenarAbstract:Nucleonic matter displays a quantum liquid structure, but in some cases finite nuclei behave like molecules composed of clusters of protons and neutrons. Clustering is a recurrent feature in light nuclei, from beryllium to nickel. For instance, in $^{12}$C the Hoyle state, crucial for stellar nucleosynthesis, can be described as a nuclear molecule consisting of three alpha-particles. The mechanism of cluster formation, however, has not yet been fully understood. We show that the origin of clustering can be traced back to the depth of the confining nuclear potential. By employing the theoretical framework of energy density functionals that encompasses both cluster and quantum liquid-drop aspects of nuclei, it is shown that the depth of the potential determines the energy spacings between single-nucleon orbitals, the localization of the corresponding wave functions and, therefore, the degree of nucleonic density clustering. Relativistic functionals, in particular, are characterized by deep single-nucleon potentials. When compared to non-relativistic functionals that yield similar ground-state properties (binding energy, deformation, radii), they predict the occurrence of much more pronounced cluster structures. More generally, clustering is considered as a transitional phenomenon between crystalline and quantum liquid phases of fermionic systems.
Stefano Gandolfi - One of the best experts on this subject based on the ideXlab platform.
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atomic nuclei from quantum monte carlo calculations with chiral eft interactions
Frontiers in Physics, 2020Co-Authors: Stefano Gandolfi, Diego Lonardoni, Alessandro Lovato, Maria PiarulliAbstract:Quantum Monte Carlo methods are powerful numerical tools to accurately solve the Schr\"odinger equation for nuclear systems, a necessary step to describe the structure and reactions of nuclei and nucleonic matter starting from realistic interactions and currents. These \textit{ab-initio} methods have been used to accurately compute properties of light nuclei -- including their spectra, moments, and transitions -- and the equation of state of neutron and nuclear matter. In this work we review selected results obtained by combining quantum Monte Carlo methods and recent Hamiltonians constructed within chiral effective field theory.
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atomic nuclei from quantum monte carlo calculations with chiral eft interactions
arXiv: Nuclear Theory, 2020Co-Authors: Stefano Gandolfi, Diego Lonardoni, Alessandro Lovato, Maria PiarulliAbstract:Quantum Monte Carlo methods are powerful numerical tools to accurately solve the Schr\"odinger equation for nuclear systems, a necessary step to describe the structure and reactions of nuclei and nucleonic matter starting from realistic interactions and currents. These ab-initio methods have been used to accurately compute properties of light nuclei -- including their spectra, moments, and transitions -- and the equation of state of neutron and nuclear matter. In this work we review selected results obtained by combining quantum Monte Carlo methods and recent Hamiltonians constructed within chiral effective field theory.
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Coupled-cluster calculations of nucleonic matter
Physical Review C, 2014Co-Authors: Gaute Hagen, Thomas Papenbrock, Andreas Ekström, K. D. A. Wendt, G. Baardsen, Stefano Gandolfi, Morten Hjorth-jensen, Charles HorowitzAbstract:Background: The equation of state (EoS) of nucleonic matter is central for the understanding of bulk nuclear properties, the physics of neutron star crusts, and the energy release in supernova explosions. Because nuclear matter exhibits a nely tuned saturation point, its EoS also constrains nuclear interactions. Purpose: This work presents coupled-cluster calculations of innite nucleonic matter using modern interactions from chiral eective eld theory (EFT). It assesses the role of correlations beyond particle-particle and hole-hole ladders, and the role of three-nucleon-forces (3NFs) in nuclear matter calculations with chiral interactions. Methods: This work employs the optimized nucleon-nucleon (NN) potential NNLOopt at next-tonext-to leading-order, and presents coupled-cluster computations of the EoS for symmetric nuclear matter and neutron matter. The coupled-cluster method employs up to selected triples clusters and the single-particle space consists of a momentum-space lattice. We compare our results with benchmark calculations and control nite-size eects and shell oscillations via twist-averaged boundary conditions. Results: We provide several benchmarks to validate the formalism and show that our results exhibit a good convergence toward the thermodynamic limit. Our calculations agree well with recent coupled-cluster results based on a partial wave expansion and particle-particle and hole-hole ladders. For neutron matter at low densities, and for simple potential models, our calculations agree with results from quantum Monte Carlo computations. While neutron matter with interactions from chiral EFT is perturbative, symmetric nuclear matter requires nonperturbative approaches. Correlations beyond the standard particle-particle ladder approximation yield non-negligible contributions. The saturation point of symmetric nuclear matter is sensitive to the employed 3NFs and the employed regularization scheme. 3NFs with nonlocal cutos exhibit a considerably improved convergence than their local cousins. We are unable to nd values for the parameters of the short-range part of the local 3NF that simultaneously yield acceptable values for the saturation point in symmetric nuclear matter and the binding energies of light nuclei. Conclusions: Coupled-cluster calculations with nuclear interactions from chiral EFT yield nonperturbative results for the EoS of nucleonic matter. Finite-size eects and eects
Diego Lonardoni - One of the best experts on this subject based on the ideXlab platform.
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atomic nuclei from quantum monte carlo calculations with chiral eft interactions
Frontiers in Physics, 2020Co-Authors: Stefano Gandolfi, Diego Lonardoni, Alessandro Lovato, Maria PiarulliAbstract:Quantum Monte Carlo methods are powerful numerical tools to accurately solve the Schr\"odinger equation for nuclear systems, a necessary step to describe the structure and reactions of nuclei and nucleonic matter starting from realistic interactions and currents. These \textit{ab-initio} methods have been used to accurately compute properties of light nuclei -- including their spectra, moments, and transitions -- and the equation of state of neutron and nuclear matter. In this work we review selected results obtained by combining quantum Monte Carlo methods and recent Hamiltonians constructed within chiral effective field theory.
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atomic nuclei from quantum monte carlo calculations with chiral eft interactions
arXiv: Nuclear Theory, 2020Co-Authors: Stefano Gandolfi, Diego Lonardoni, Alessandro Lovato, Maria PiarulliAbstract:Quantum Monte Carlo methods are powerful numerical tools to accurately solve the Schr\"odinger equation for nuclear systems, a necessary step to describe the structure and reactions of nuclei and nucleonic matter starting from realistic interactions and currents. These ab-initio methods have been used to accurately compute properties of light nuclei -- including their spectra, moments, and transitions -- and the equation of state of neutron and nuclear matter. In this work we review selected results obtained by combining quantum Monte Carlo methods and recent Hamiltonians constructed within chiral effective field theory.
G Hagen - One of the best experts on this subject based on the ideXlab platform.
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coupled cluster computations of atomic nuclei
Reports on Progress in Physics, 2014Co-Authors: G Hagen, T Papenbrock, M Hjorthjensen, D J DeanAbstract:In the past decade, coupled-cluster theory has seen a renaissance in nuclear physics, with computations of neutron-rich and medium-mass nuclei. The method is efficient for nuclei with product-state references, and it describes many aspects of weakly bound and unbound nuclei. This report reviews the technical and conceptual developments of this method in nuclear physics, and the results of coupled-cluster calculations for nucleonic matter, and for exotic isotopes of helium, oxygen, calcium, and some of their neighbors.
