Nuclear Theory·nucl-th

Tuesday·November 2, 2021

15 papers—7 primary·8 cross-listed

01
[Submitted on 30 Oct 2021]
Solving the three-dimensional Skyrme Hartree-Fock-Bogoliubov problem using the mixed-basis method
Yue Shi · Nobuo Hinohara
Background: The symmetry-unrestricted Hartree-Fock-Bogoliubov (HFB) simulation is important for describing various quantum many-body systems. However, the HFB problem in Cartesian coordinate space is numerically challenging. Purpose: For describing ground states without imposing axial symmetry and looking ahead to future extension for dynamics with full time dependence, we present a numerically efficient implementation of the three-dimensional (3D) HFB code. Methods: We develop a 3D Skyrme HFB code based on the mixed-basis representation (HFBmix) which consists of two harmonic-oscillator (HO) bases in the x- and y-directions, and finite-difference (FD) basis in the z-direction in solving the nuclear 3D HFB problem. Results: The results show very well agreement among all the three codes (HFBmix, HO3D, and hfodd). Especially for the HF calculations, the differences in total energies are on the order of a few keV for the lightest O and Mg nuclei. The HFBmix is applied to spherical, prolate, and triaxial systems, and gives the same quadrupole moments for the deformed nuclei as those of the HO-based calculations. Feasibility of the HFBmix is demonstrated in the fission isomer and barrier calculations of 240Pu. Conclusions: The HFBmix is useful for solving the nuclear 3D HFB problem for its numerical efficiency. Future work will include the analysis of deformed drip-line systems and systematic potential-energy surface calculation for fission-path analysis as well as the time-dependent extension of the HFBmix code for dynamics calculations.
Comments:
18 pages, 4 figures
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2111.00144 [pdf]
2 citations
02
[Submitted on 30 Oct 2021]
Statistical uncertainty estimation of higher-order cumulants with finite efficiency and its application in heavy-ion collisions
Fan Si · Yifei Zhang
We derive the general analytical expressions for the statistical uncertainties of cumulants up to fourth order including an efficiency correction. The analytical expressions have been tested with a toy Monte Carlo model analysis. An application to the study of particle multiplicity fluctuations in heavy-ion collisions is investigated. In this derivation, a mathematical proof is given that the validity of an averaged efficiency correction and the fluctuations induced by the non-uniformity of efficiency can be eliminated. The estimation of statistical uncertainties using the analytical formulas is found to be significantly faster than the commonly used bootstrap method. The simplicity and efficiency of using the analytical formulas may be useful for massive data analysis in many fields.
Comments:
16 pages, 2 figures
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2111.00238 [pdf]
PRC(2022)·0 citations
03
[Submitted on 1 Nov 2021]
Local two- and three-nucleon chiral interactions
Maria Piarulli🇺🇸 · Rocco Schiavilla🇺🇸
Understanding the structure and reactions of nuclei from first principles has been a long-standing goal of nuclear physics. In this respect, few- and many-body systems provide a unique laboratory for studying nuclear interactions. In the past couple of decades, the modeling of nuclear interactions has progressed significantly owing, in particular, to the development of chiral effective field theory ( $χ$ EFT), a low-energy effective representation of quantum chromodynamics (QCD). Within $χ$ EFT, many studies have dealt with the construction of both two- and three-nucleon interactions. The aim of the present article is to provide a concise account of chiral interaction models that are local in configuration space, and to report on a selection of recent results for nuclear systems obtained with these interactions.
Comments:
14 pages, 2 figures, Contribution to Special Issue of Few-Body Systems: Celebrating 30 years of Steven Weinberg's papers on Nuclear Forces from Chiral Lagrangians
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2111.00675 [pdf]
Few Body Syst.(2021)·3 citations
04
[Submitted on 1 Nov 2021]
Multi-reference many-body perturbation theory for nuclei II -- Ab initio study of neon isotopes via PGCM and IM-NCSM calculations
Mikael Frosini🇫🇷 · Thomas Duguet🇫🇷 · Jean-Paul Ebran🇫🇷 · Benjamin Bally🇪🇸 · Tobias Mongelli🇩🇪 · Tomás R. Rodríguez🇪🇸 · Robert Roth🇩🇪 · Vittorio Somà🇫🇷
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 isotope. This second (i.e. Paper II) of the present series proposes an extensive ab initio study of neon isotopes based on two complementary many-body methods, i.e. the quasi-exact in-medium no-core shell model (IM-NCSM) and the projected generator coordinate method (PGCM) that is ideally suited to capturing strong static correlations associated with shape deformation and fluctuations. Calculations employ a state-of-the-art generation of chiral effective field theory Hamiltonians and evaluate the associated systematic uncertainties. In spite of missing so-called dynamical correlations, which can be added via the multi-reference perturbation theory proposed in the first paper (i.e. Paper I) of the present series, the PGCM is shown to be a suitable method to tackle the low-lying spectroscopy of complex nuclei. Still, describing the physics of the island of inversion constitutes a challenge that seems to require the inclusion of dynamical correlations. This is addressed in the third paper (i.e. Paper III) of the present series.
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2111.00797 [pdf]
EPJA(2022)·97 citations
05
[Submitted on 1 Nov 2021]
Forward coherent $ω$ and $ϕ$ mesons production in the photon induced reaction on nuclei
Swapan Das🇮🇳
The differential cross sections of the forward coherent $ω$ and $ϕ$ mesons photoproduction from nuclei have been calculated using the Glauber model for the nuclear reaction. The measured cross section of the elementary reaction, i.e., $γ N \to ω (ϕ) N$ reaction, are used as input in the Glauber model. The experimentally determined free-space scattering parameters of the quoted mesons have been used to evaluate the meson nucleus interactions. The sensitivity of the cross section to the Fermi-motion of the nucleon and the nucleon-nucleon short-range correlation in the nucleus are studied. The calculated results are compared with the measured cross sections.
Comments:
Preprint - 15 pages, 4 figures
Subjects:
Nuclear Theory (nucl-th); Nuclear Experiment (nucl-ex)
arXiv:
2111.00810 [pdf]
Phys.Scripta(2021)·2 citations
06
[Submitted on 1 Nov 2021]
Proton-neutron pairing and binding energies of nuclei close to N=Z line
D. Negrea · N. Sandulescu · D. Gambacurta
We analyse the contribution of isovector and isoscalar proton-neutron pairing to the binding energies of even-even nuclei with $N - Z = 0, 2, 4$ and atomic mass $20 < A < 100$ . The binding energies are calculated in the mean-field approach by coupling a Skyrme-type functional to an isovector-isoscalar pairing force of zero range. The latter is treated in the framework of quartet condensation model (QCM), which conserves exactly the particle number and the isospin. The interdependence of pairing and deformation is taken into account by performing self-consistent Skyrme-HF+QCM calculations in the intrinsic system. It is shown that the binding energies are not changing much when the isoscalar pairing is switched on. This fact is related to the off-diagonal matrix elements of the pairing force, which is less attractive for the isoscalar force, and to the competition between the isoscalar and isovector pairing channels.
Comments:
14 pages, 7 figures
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2111.00878 [pdf]
PRC(2022)·5 citations
07
[Submitted on 1 Nov 2021]
What Can Possibly Go Wrong?
Harald W. Griesshammer (George Washington U.)🇺🇸
A lot. [In this hard, unbiased and objective look at some past and continuing blunders in following Weinberg's suggestions to arrive at a comprehensive description of Nuclear Physics using Effective Field Theories, some names and citations are withheld to protect the innocent.]
Comments:
20 pages LaTeX2e (pdflatex) including 4 figures as .pdf files using includegraphics and svjour3. Text-identical to publication in Few-Body Systems, Special Issue "Celebrating 30 years of the Steven Weinberg's paper Nuclear Forces from Chiral Lagrangians", but correcting journal's erroneous placing of motto
Subjects:
Nuclear Theory (nucl-th); High Energy Physics — Phenomenology (hep-ph); History and Philosophy of Physics (physics.hist-ph)
arXiv:
2111.00930 [pdf]
Few Body Syst.(2022)·14 citations
08
[Submitted on 28 Oct 2021] (cross-list from math.AP)
Godunov variables and convex entropy for relativistic fluid dynamics with bulk viscosity
Heiner Olbermann
Based on the conservation-dissipation formalism proposed by Zhu and collaborators we formulate a general version of the Israel-Stewart theory for relativistic fluid dynamics with bulk viscosity. Our generalization consists in allowing for a wide range of dependence of the entropy density on the bulk viscosity. We show the existence of Godunov-Boillat variables for this model. By known properties of systems possessing such variables, this provides an alternative proof of the recently established existence of solutions for the Israel-Stewart theory locally in time, and a proof that entropy production is positive across weak Lax shocks.
Comments:
10 pages, v2: introduction modified, references added
Subjects:
math.AP (math.AP); Nuclear Theory (nucl-th)
arXiv:
2110.15223 [pdf]
J.Math.Phys.(2022)·0 citations
09
[Submitted on 29 Oct 2021] (cross-list from hep-ph)
Radial oscillations of quark stars admixed with dark matter
José C. Jiménez🇧🇷 · Eduardo S. Fraga🇧🇷
We investigated compact stars consisting of cold quark matter and fermionic dark matter treated as two admixed fluids. We computed the stellar structures and fundamental radial oscillation frequencies for different masses of the dark fermion in the cases of weak and strong self-interacting dark matter. We found that the fundamental frequency can be dramatically modified and, in some cases, stable dark strange planets and dark strangelets with very low masses and radii can be formed.
Comments:
v2: 27 pages, 8 figures, some technical details and minor clarifications added, matches published version
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Astrophysical Phenomena (astro-ph.HE); General Relativity and Quantum Cosmology (gr-qc); Nuclear Theory (nucl-th)
arXiv:
2111.00091 [pdf]
Universe(2022)·30 citations
10
[Submitted on 31 Oct 2021] (cross-list from hep-lat)
Gliding down the QCD transition line, from $N_{f} = 2$ till the onset of conformality
A.Yu. Kotov (Fachhochsch., Julich and Dubna, JINR)🇩🇪 · M.P. Lombardo (INFN, Florence)🇮🇹 · A. Trunin (Samara U.)🇷🇺
We review the hot QCD transition with varying number of flavors, from two till the onset of the conformal window. We discuss the universality class for $N_{f} = 2$ , along the critical line for two massless light flavors, and a third flavor whose mass serves as an interpolator between $N_{f} = 2$ and $N_{f} = 3$ . We identify a possible scaling window for the 3D $O (4)$ universality class transition, and its crossover to a mean field behaviour. We follow the transition from $N_{f} = 3$ to larger $N_{f}$ , when it remains of first order, with an increasing coupling strength; we summarize its known properties, including possible cosmological applications as a model for a strong electroweak transition. The first order transition, and its accompanying second order endpoint, finally morphs into the essential singularity at the onset of the conformal window, following the singular behaviour predicted by the Functional Renormalization Group.
Comments:
30 pages, 9 figures
Subjects:
High Energy Physics — Lattice (hep-lat); High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Theory (hep-th); Nuclear Theory (nucl-th)
arXiv:
2111.00569 [pdf]
Symmetry(2021)·18 citations
11
[Submitted on 31 Oct 2021] (cross-list from physics.comp-ph)
H2ZIXY: Pauli spin matrix decomposition of real symmetric matrices
Rocco Monteiro Nunes Pesce🇬🇧 · Paul D. Stevenson🇬🇧
We present a code in Python3 which takes a square real symmetric matrix, of arbitrary size, and decomposes it as a tensor product of Pauli spin matrices. The application to the decomposition of a Hamiltonian of relevance to nuclear physics for implementation on quantum computer is given.
Comments:
8 pages
Subjects:
Computational Physics (physics.comp-ph); Nuclear Theory (nucl-th); Quantum Physics (quant-ph)
arXiv:
2111.00627 [pdf]
16 citations
12
[Submitted on 1 Nov 2021] (cross-list from astro-ph.HE)
Dissipative superfluid relativistic magnetohydrodynamics of a multicomponent fluid: the combined effect of particle diffusion and vortices
Vasiliy A. Dommes · Mikhail E. Gusakov
We formulate dissipative magnetohydrodynamic equations for finite-temperature superfluid and superconducting charged relativistic mixtures, taking into account the effects of particle diffusion and possible presence of Feynman-Onsager and/or Abrikosov vortices in the system. The equations depend on a number of phenomenological transport coefficients, which describe, in particular, relative motions of different particle species and their interaction with vortices. We demonstrate how to relate these transport coefficients to the mutual friction parameters and momentum transfer rates arising in the microscopic theory. The resulting equations can be used to study, in a unified and coherent way, a very wide range of phenomena associated with dynamical processes in neutron stars, e.g., the magnetothermal evolution, stellar oscillations and damping, as well as development and suppression of various hydrodynamic instabilities in neutron stars.
Comments:
30 pages, accepted for publication in PRD
Subjects:
High Energy Astrophysical Phenomena (astro-ph.HE); General Relativity and Quantum Cosmology (gr-qc); Nuclear Theory (nucl-th)
arXiv:
2111.00999 [pdf]
PRD(2021)·10 citations
13
[Submitted on 1 Nov 2021] (cross-list from hep-ph)
Complementarity between neutrinoless double beta decay and collider searches for heavy neutrinos in composite-fermion models
S. Biondini🇨🇭 · S. Dell'Oro🇮🇹 · R. Leonardi🇮🇹 · S. Marcocci🇺🇸 · O. Panella🇮🇹 · M. Presilla🇮🇹 · F. Vissani🇮🇹
Composite-fermion models predict excited quarks and leptons with mass scales which can potentially be observed at high-energy colliders like the LHC; the most recent exclusion limits from the CMS and ATLAS Collaborations corner excited-fermion masses and the compositeness scale to the multi-TeV range. At the same time, hypothetical composite Majorana neutrinos would lead to observable effects in neutrinoless double beta decay ( $0 ν β β$ ) experiments. In this work, we show that the current composite-neutrino exclusion limit $M_{N} > 4.6$ TeV, as extracted from direct searches at the LHC, can indeed be further improved to $M_{N} > 8.8$ TeV by including the bound on the nuclear transition $^{136}$ Xe $\to$ $^{136}$ Ba $+ 2 e^{-}$ . Looking ahead, the forthcoming HL-LHC will allow probing a larger portion of the parameter-space, nevertheless, it will still benefit from the complementary limit provided by $0 ν β β$ future detectors to explore composite-neutrino masses up to $12.6$ TeV.
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2111.01053 [pdf]
4 citations
14
[Submitted on 1 Nov 2021] (cross-list from hep-ph)
Asymptotics of transverse momentum broadening in dense QCD media
Paul Caucal🇺🇸
We study the asymptotic behaviour of the transverse momentum broadening distribution of an energetic quark or gluon propagating through dense QCD matter, in the large system size $L$ limit, taking into account radiative corrections in the double logarithmic approximation. Thanks to a connection between the evolution of the jet quenching parameter $q^$ and the formation of traveling wave fronts in nonlinear physics, we obtain a formula for the $L$ dependence of the characteristic transverse momentum scale $Q_{s}$ of the distribution valid up to terms of order $1/ ln (L)$ . We briefly discuss the physical implications of this formula for jet quenching and small- $x$ phenomenology.
Comments:
7 pages, proceeding of the 50th International Symposium on Multiparticle Dynamics (ISMD2021)
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2111.01088 [pdf]
SciPost Phys.Proc.(2022)·0 citations
15
[Submitted on 1 Nov 2021] (cross-list from hep-lat)
Connecting Matrix Elements to Multi-Hadron Form-Factors
Andrew W. Jackura🇺🇸
We discuss developments in calculating multi-hadron form-factors and transition processes via lattice QCD. Our primary tools are finite-volume scaling relations, which map spectra and matrix elements to the corresponding multi-hadron infinite-volume amplitudes. We focus on two hadron processes probed by an external current, and provide various checks on the finite-volume formalism in the limiting cases of perturbative interactions and systems forming a bound state. By studying model-independent properties of the infinite-volume amplitudes, we are able to rigorously define form-factors of resonances.
Comments:
11 pages, 6 figures, proceedings to the 38th International Symposium on Lattice Field Theory (LATTICE21), 26-30 July 2021, Zoom/Gather@Massachusetts Institute of Technology
Subjects:
High Energy Physics — Lattice (hep-lat); High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2111.01098 [pdf]
PoS(2022)·0 citations

Affiliations

first authorsco-authorsvia INSPIRE