Coordinate-space solver for superfluid many-fermion systems with the shifted conjugate-orthogonal conjugate-gradient method

Jin, Shi; Bulgac, Aurel; Roche, Kenneth J.; Wlazłowski, Gabriel

doi:10.1103/physrevc.95.044302

Cited by 46 publications

(63 citation statements)

References 74 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As discussed in Section II A, this suppresses the effect of the non-physical discretisation of the states in the continuum, hence reducing the associated uncertainty on the HFB total energy to ≈ 1 keV per particle. Although more advanced HFB methods are now available to properly treat continuum states [48][49][50][51][52], it is still unclear if these methods can deal with very large WS cells especially in terms of execution time. We leave this analysis for a forthcoming project.…”

Section: The Methodsmentioning

confidence: 99%

A new statistical method for the structure of the inner crust of neutron stars

Pastore¹,

Shelley²,

Baroni³

et al. 2017

J. Phys. G: Nucl. Part. Phys.

View full text Add to dashboard Cite

We investigated the structure of the low density regions of the inner crust of neutron stars using the Hartree-Fock-Bogoliubov (HFB) model to predict the proton content Z of the nuclear clusters and, together with the lattice spacing, the proton content of the crust as a function of the total baryonic density ρ b . The exploration of the energy surface in the (Z, ρ b ) configuration space and the search for the local minima require thousands of calculations. Each of them implies an HFB calculation in a box with a large number of particles, thus making the whole process very demanding. In this work, we apply a statistical model based on a Gaussian Process Emulator that makes the exploration of the energy surface ten times faster. We also present a novel treatment of the HFB equations that leads to an uncertainty on the total energy of ≈ 4 keV per particle. Such a high precision is necessary to distinguish neighbour configurations around the energy minima.

show abstract

Section: The Methodsmentioning

confidence: 99%

A new statistical method for the structure of the inner crust of neutron stars

Pastore¹,

Shelley²,

Baroni³

et al. 2017

J. Phys. G: Nucl. Part. Phys.

View full text Add to dashboard Cite

show abstract

“…Therefore, it is useful to eliminate the derivative ∇ 2 in expressions of Eqs. (22) and (23). The calculation of the spin-current density J (r) is done by…”

Section: Kinetic and Spin-current Densities In Parallel Computingmentioning

confidence: 99%

“…It is slightly more complicated than the zero-temperature HFB in Ref. [22], because we need to remove contributions from the Matsubara frequencies on the imaginary axis. In Sec.…”

Section: Introductionmentioning

confidence: 99%

Coordinate-space solver for finite-temperature Hartree-Fock-Bogoliubov calculations using the shifted Krylov method

Kashiwaba

Nakatsukasa

2020

Phys. Rev. C

View full text Add to dashboard Cite

Background: In order to study structure of proto-neutron stars and those in subsequent cooling stages, it is of great interest to calculate inhomogeneous hot and cold nuclear matter in a variety of phases. The finite-temperature Hartree-Fock-Bogoliubov (FT-HFB) theory is a primary choice for this purpose, however, its numerical calculation for superfluid (superconducting) many-fermion systems in three dimensions requires enormous computational costs. Purpose: To study a variety of phases in the crust of hot and cold neutron stars, we propose an efficient method to perform the FT-HFB calculation with the three-dimensional (3D) coordinatespace representation. Methods: Recently, an efficient method based on the contour integral of Green's function with the shifted conjugate-orthogonal conjugate-gradient method has been proposed [Phys. Rev. C 95, 044302 (2017)]. We extend the method to the finite temperature, using the shifted conjugateorthogonal conjugate-residual method. Results: We benchmark the 3D coordinate-space solver of the FT-HFB calculation for hot isolated nuclei and fcc phase in the inner crust of neutron stars at finite temperature. The computational performance of the present method is demonstrated. Different critical temperatures of the quadrupole and the octupole deformations are confirmed for 146 Ba. The robustness of the shape coexistence feature in 184 Hg is examined. For the neutron-star crust, the deformed neutron-rich Se nuclei embedded in the sea of superfluid low-density neutrons appear in the fcc phase at the nucleon density of 0.045 fm −3 and the temperature of kBT = 200 keV. Conclusions: The efficiency of the developed solver is demonstrated for nuclei and inhomogeneous nuclear matter at finite temperature. It may provide a standard tool for nuclear physics, especially for the structure of the hot and cold neutron-star matters.

show abstract

“…Next, we started selfconsistent iterations to compute densities from Green's functions, using the method very similar to the one applied in studies of large electronic systems [3,4]. The method extracts densities without explicit diagonalization of HFB matrix (for details see [5]). To get a state with a vortex in each iteration we imprinted the correct phase dependence on the neutron paring potential ∆.…”

Section: Initial Configurationsmentioning

confidence: 99%

“…As these vortices "creep" through the crust, they transfer this angular momentum to the crust. Glitches result from a catastrophic release of pinned vorticity [5] that suddenly changes the pulsation rate.…”

mentioning

confidence: 99%

Vortex Pinning and Dynamics in the Neutron Star Crust

et al. 2016

Self Cite

View full text Add to dashboard Cite

The nature of the interaction between superfluid vortices and the neutron star crust, conjectured by Anderson and Itoh in 1975 to be at the heart vortex creep and the cause of glitches, has been a long-standing question in astrophysics. Using a qualitatively new approach, we follow the dynamics as superfluid vortices move in response to the presence of "nuclei" (nuclear defects in the crust). The resulting motion is perpendicular to the force, similar to the motion of a spinning top when pushed. We show that nuclei repel vortices in the neutron star crust, and characterize the force as a function of the vortex-nucleus separation.

show abstract

Coordinate-space solver for superfluid many-fermion systems with the shifted conjugate-orthogonal conjugate-gradient method

Cited by 46 publications

References 74 publications

A new statistical method for the structure of the inner crust of neutron stars

A new statistical method for the structure of the inner crust of neutron stars

Coordinate-space solver for finite-temperature Hartree-Fock-Bogoliubov calculations using the shifted Krylov method

Vortex Pinning and Dynamics in the Neutron Star Crust

Contact Info

Product

Resources

About