Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

arXiv:0712.1364

The Auxiliary Field Diffusion Monte Carlo Method for Nuclear Physics and Nuclear Astrophysics

Stefano Gandolfi

Published Dec 9, 2007• 8 citations
arXivHTMLPDF

Abstract

In this thesis, I discuss the use of the Auxiliary Field Diffusion Monte Carlo method to compute the ground state of nuclear Hamiltonians, and I show several applications to interesting problems both in nuclear physics and in nuclear astrophysics. In particular, the AFDMC algorithm is applied to the study of several nuclear systems, finite, and infinite matter. Results about the ground state of nuclei ($^4$He, $^8$He, $^{16}$O and $^{40}$Ca), neutron drops (with 8 and 20 neutrons) and neutron rich-nuclei (isotopes of oxygen and calcium) are discussed, and the equation of state of nuclear and neutron matter are calculated and compared with other many-body calculations. The $^1S_0$ superfluid phase of neutron matter in the low-density regime was also studied.

DOI
10.48550/arxiv.0712.1364

Related papers

Perturbative treatment of nonlocal chiral interactions in auxiliary-field diffusion Monte Carlo calculations

Ryan Curry, Rahul Somasundaram, Stefano Gandolfi +2 more

Nuclear many-body systems, ranging from nuclei to neutron stars, are some of the most interesting physical phenomena in our universe, and quantum Monte Carlo (QMC) approaches are among the most accurate many-body methods currently available to study them. In recent decades, interactions derived from chiral effective field theory (EFT) have been widely adopted in the study of nuclear many-body systems. One drawback of the QMC approach is the requirement that the nuclear interactions need to be local, whereas chiral EFT interactions usually contain nonlocalities. In this work, we leverage the capability of computing second-order perturbative corrections to the ground-state energy in order to develop a self-consistent approach to including nonlocal operators in QMC calculations. We investigate both the deuteron and the neutron-matter equation of state in order to show the robustness of our technique and pave the way for future QMC calculations at higher orders in the EFT, where nonlocal operators cannot be avoided.

arXiv:2409.16365•Physical Review C•Jan 2, 2025•7 citations

Quantum Monte Carlo approaches to nuclear and atomic physics

J. Carlson, Stefano Gandolfi, Alexandros Gezerlis

Quantum Monte Carlo methods have proven to be valuable in the study of strongly correlated quantum systems, particularly nuclear physics and cold atomic gases. Historically, such ab initio simulations have been used to study properties of light nuclei, including spectra and form factors, low-energy scattering, and high-momentum properties including inclusive scattering and one- and two-body momentum distributions. More recently they have been used to study the properties of homogeneous and inhomogeneous neutron matter and cold atomic gases. There are close analogies between these seemingly diverse systems, including the equation of state, superfluid pairing, and linear response to external probes. In this paper, we compare and contrast results found in nuclear and cold atom physics. We show updated lattice results for the energy of the homogeneous unitary Fermi gas and comparisons with neutron matter, as well as for the dependence of the cold atom energy on the mass ratio between paired particles, which yields insights on the structure of the ground state. We also provide new lattice and continuum results for the harmonically trapped unitary gas, again comparing neutron matter and cold atoms.

arXiv:1210.6659•Progress of Theoretical and Experimental Physics•Jan 1, 2012•72 citations

1Quantum Monte Carlo Approaches to Nuclear and Atomic Physics

Joseph Carlson, Stefano G, Ros Gezerlis

Quantum Monte Carlo methods have proven to be valuable in the study of strongly correlated quantum systems, particularly nuclear physics and cold atomic gases. Historically, such ab initio simulations have been used to study properties of light nuclei, including spectra and form factors, low-energy scattering, and high-momentum properties including inclusive scattering and one- and two-body momentum distributions. More recently they have been used to study the properties of homogeneous and inhomogeneous neutron matter and cold atomic gases. There are close analogies between these seemingly diverse systems, including the equation of state, superfluid pairing, and linear response to external probes. In this paper, we compare and contrast results found in nuclear and cold atom physics. We show updated lattice results for the energy of the homogeneous unitary Fermi gas and comparisons with neutron matter, as well as for the dependence of the cold atom energy on the mass ratio between paired particles, which yields insights on the structure of the ground state. We also provide new lattice and continuum results for the harmonically trapped unitary gas, again comparing neutron matter and cold atoms. Quantum Monte Carlo methods1), 2) have been proven very valuable in study-ing a host of strongly correlated quantum systems, including solid and liquid He-lium,3), 4), 5), 6) electronic systems,7), 8) light nuclei9), 10), 11) and more recently neutron

•Aug 17, 2016•24 citations

Demonstration of the auxiliary-field Monte Carlo approach forsd-shell nuclei

W. E. Ormand, David J. Dean, C. W. Johnson +2 more

We apply the auxiliary-field Monte Carlo approach to the nuclear shell model in the 1s-0d configuration space. The Hamiltonian was chosen to have isovector pairing and isoscalar multipole-multipole interactions, and the calculations were performed within the fixed-particle, canonical ensemble. The results demonstrate the feasibility of the method for N\ensuremath{\ne}Z even-even and odd-odd N=Z nuclei. In particular, static observables for even-even Ne isotopes and $^{22}\mathrm{Na}$ compare well with results obtained from exact diagonalization of the Hamiltonian. Response functions are presented for $^{22}\mathrm{Ne}$ and compared with exact results, and the viability of cranked calculations for N\ensuremath{\ne}Z even-even nuclei is addressed. We present methods for computing observables in the canonical ensemble using Fourier extraction, and for determining the nucelar shape.

arXiv:nucl-th/9307018•Physical Review C•Mar 1, 1994•73 citations

Auxiliary field Quantum Monte Carlo for dilute neutrons on the lattice

Ryan Curry, J. Dissanayake, Stefano Gandolfi +1 more

We employ constrained path Auxiliary Field Quantum Monte Carlo (AFQMC) in the pursuit of studying physical nuclear systems using a lattice formalism. Since AFQMC has been widely used in the study of condensed-matter systems such as the Hubbard model, we benchmark our method against published results for both one- and two-dimensional Hubbard model calculations. We then turn our attention to cold atomic and nuclear systems. We use an onsite contact interaction that can be tuned in order to reproduce the known scattering length and effective range of a given interaction. Developing this machinery allows us to extend our calculations to study nuclear systems within a lattice formalism. We perform initial calculations for a range of nuclear systems from two- to few-body neutron systems. This article is part of the theme issue 'The liminal position of Nuclear Physics: from hadrons to neutron stars'.

arXiv:2310.01504•Philosophical Transactions of the Royal Society A Mathematical Physical and Engineering Sciences•Jun 24, 2024•5 citations

Quantum Monte Carlo with non-local chiral interactions

Alessandro Roggero, A Mukherjee, Francesco Pederiva

Quantum Monte Carlo methods have been used very successfully to calculate the ground state properties of a variety of nuclear and other strongly interacting many body systems. An exciting recent development in low energy nuclear physics is the formulation of nuclear Hamiltonians based on the symmetries of quantum chromodynamics via chiral effective field theory. However, the usual coordinate space based quantum Monte Carlo implementation is unsuitable for these Hamiltonians due to the presence of non-localites. Here we report on our recent work in developing a new quantum Monte Carlo algorithm suitable for these non-local Hamiltonians, and present some results for pure neutron matter.

Journal of Physics Conference Series•Jul 7, 2014•2 citations
In this thesis, I discuss the use of the Auxiliary Field Diffusion Monte Carlo method to compute the ground state of nuclear Hamiltonians, and I show several applications to interesting problems both in nuclear physics and in nuclear astrophysics. In particular, the AFDMC algorithm is applied to the study of several nuclear systems, finite, and infinite matter. Results about the ground state of nuclei (4^44He, 8^88He, 16^{16}16O and 40^{40}40Ca), neutron drops (with 8 and 20 neutrons) and neutron rich-nuclei (isotopes of oxygen and calcium) are discussed, and the equation of state of nuclear and neutron matter are calculated and compared with other many-body calculations. The 1S0^1S_01S0​ superfluid phase of neutron matter in the low-density regime was also studied.
Nuclear many-body systems, ranging from nuclei to neutron stars, are some of the most interesting physical phenomena in our universe, and quantum Monte Carlo (QMC) approaches are among the most accurate many-body methods currently available to study them. In recent decades, interactions derived from chiral effective field theory (EFT) have been widely adopted in the study of nuclear many-body systems. One drawback of the QMC approach is the requirement that the nuclear interactions need to be local, whereas chiral EFT interactions usually contain nonlocalities. In this work, we leverage the capability of computing second-order perturbative corrections to the ground-state energy in order to develop a self-consistent approach to including nonlocal operators in QMC calculations. We investigate both the deuteron and the neutron-matter equation of state in order to show the robustness of our technique and pave the way for future QMC calculations at higher orders in the EFT, where nonlocal operators cannot be avoided.
Quantum Monte Carlo methods have proven to be valuable in the study of strongly correlated quantum systems, particularly nuclear physics and cold atomic gases. Historically, such ab initio simulations have been used to study properties of light nuclei, including spectra and form factors, low-energy scattering, and high-momentum properties including inclusive scattering and one- and two-body momentum distributions. More recently they have been used to study the properties of homogeneous and inhomogeneous neutron matter and cold atomic gases. There are close analogies between these seemingly diverse systems, including the equation of state, superfluid pairing, and linear response to external probes. In this paper, we compare and contrast results found in nuclear and cold atom physics. We show updated lattice results for the energy of the homogeneous unitary Fermi gas and comparisons with neutron matter, as well as for the dependence of the cold atom energy on the mass ratio between paired particles, which yields insights on the structure of the ground state. We also provide new lattice and continuum results for the harmonically trapped unitary gas, again comparing neutron matter and cold atoms.
Quantum Monte Carlo methods have proven to be valuable in the study of strongly correlated quantum systems, particularly nuclear physics and cold atomic gases. Historically, such ab initio simulations have been used to study properties of light nuclei, including spectra and form factors, low-energy scattering, and high-momentum properties including inclusive scattering and one- and two-body momentum distributions. More recently they have been used to study the properties of homogeneous and inhomogeneous neutron matter and cold atomic gases. There are close analogies between these seemingly diverse systems, including the equation of state, superfluid pairing, and linear response to external probes. In this paper, we compare and contrast results found in nuclear and cold atom physics. We show updated lattice results for the energy of the homogeneous unitary Fermi gas and comparisons with neutron matter, as well as for the dependence of the cold atom energy on the mass ratio between paired particles, which yields insights on the structure of the ground state. We also provide new lattice and continuum results for the harmonically trapped unitary gas, again comparing neutron matter and cold atoms. Quantum Monte Carlo methods1), 2) have been proven very valuable in study-ing a host of strongly correlated quantum systems, including solid and liquid He-lium,3), 4), 5), 6) electronic systems,7), 8) light nuclei9), 10), 11) and more recently neutron
We apply the auxiliary-field Monte Carlo approach to the nuclear shell model in the 1s-0d configuration space. The Hamiltonian was chosen to have isovector pairing and isoscalar multipole-multipole interactions, and the calculations were performed within the fixed-particle, canonical ensemble. The results demonstrate the feasibility of the method for N\ensuremath{\ne}Z even-even and odd-odd N=Z nuclei. In particular, static observables for even-even Ne isotopes and 22Na^{22}\mathrm{Na}22Na compare well with results obtained from exact diagonalization of the Hamiltonian. Response functions are presented for 22Ne^{22}\mathrm{Ne}22Ne and compared with exact results, and the viability of cranked calculations for N\ensuremath{\ne}Z even-even nuclei is addressed. We present methods for computing observables in the canonical ensemble using Fourier extraction, and for determining the nucelar shape.
We employ constrained path Auxiliary Field Quantum Monte Carlo (AFQMC) in the pursuit of studying physical nuclear systems using a lattice formalism. Since AFQMC has been widely used in the study of condensed-matter systems such as the Hubbard model, we benchmark our method against published results for both one- and two-dimensional Hubbard model calculations. We then turn our attention to cold atomic and nuclear systems. We use an onsite contact interaction that can be tuned in order to reproduce the known scattering length and effective range of a given interaction. Developing this machinery allows us to extend our calculations to study nuclear systems within a lattice formalism. We perform initial calculations for a range of nuclear systems from two- to few-body neutron systems. This article is part of the theme issue 'The liminal position of Nuclear Physics: from hadrons to neutron stars'.
Quantum Monte Carlo methods have been used very successfully to calculate the ground state properties of a variety of nuclear and other strongly interacting many body systems. An exciting recent development in low energy nuclear physics is the formulation of nuclear Hamiltonians based on the symmetries of quantum chromodynamics via chiral effective field theory. However, the usual coordinate space based quantum Monte Carlo implementation is unsuitable for these Hamiltonians due to the presence of non-localites. Here we report on our recent work in developing a new quantum Monte Carlo algorithm suitable for these non-local Hamiltonians, and present some results for pure neutron matter.