Nuclear Theory·nucl-th

Monday·April 13, 2020

6 papers—3 primary·3 cross-listed

01
[Submitted on 10 Apr 2020]
Constraints on the neutron drip-line with the newly observed 39Na
Q.Z. Chai · J.C. Pei · Na Fei · D.W. Guan
The recently observed weakly-bound 39Na provides a stringent theoretical constraint on the neutron drip-line. We studied the properties of drip-line nuclei around 39Na with the Hartree-Fock-Bogoliubov method and various Skyrme interactions. We adopted the extended SkM*-ext1 parameterization which can properly describe two-neutron separation energies of oxygen and fluorine isotopes and deformations at the center of the "island of inversion". Systematic calculations of drip lines of O, F, Ne, Na, Mg, and Al isotopes have been performed. We infer that 42Mg is weakly bound and 45Al is less weakly bound. 44Mg and 47Al could be barely existed. We also demonstrated the deformed halo properties of 39Na. Our studies could be valuable for experimental explorations of drip-line nuclei in the forthcoming FRIB and other rare-isotope beam facilities .
Comments:
6 pages, 4 figures, submitted
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2004.04897 [pdf]
PRC(2020)·17 citations
02
[Submitted on 10 Apr 2020]
Neutron dominance in excited states of $^{26}$ Mg and $^{10}$ Be probed by proton and alpha inelastic scattering
Yoshiko Kanada-En'yo · Yuki Shikata · Yohei Chiba · Kazuyuki Ogata
Isospin characters of nuclear excitations in $^{26}$ Mg and $^{10}$ Be are investigated via proton( $p$ ) and alpha( $α$ ) inelastic scattering. A structure model of antisymmetrized molecular dynamics (AMD) is applied to calculate the ground and excited states of $^{26}$ Mg and $^{10}$ Be. The calculation describes the isoscalar feature of the ground-band $2_{1}^{+}$ ( $K^{π} = 0_{1}^{+}$ ) excitation and predicts the neutron dominance of the side-band $2_{2}^{+}$ ( $K^{π} = 2^{+}$ ) excitation in $^{26}$ Mg and $^{10}$ Be. The $p$ and $α$ inelastic scattering off $^{26}$ Mg and $^{10}$ Be is calculated by microscopic coupled-channel (MCC) calculations with a $g$ -matrix folding approach by using the matter and transition densities of the target nuclei calculated with AMD. The calculation reasonably reproduces the observed $0_{1}^{+}$ , $2_{1}^{+}$ , and $2_{2}^{+}$ cross sections of $^{26}$ Mg+ $p$ scattering at incident energies $E_{p} =$ 24 and 40 MeV and of $^{26}$ Mg+ $α$ scattering at $E_{α} =$ 104 and 120 MeV. For $^{10}$ Be+ $p$ and $^{10}$ Be+ $α$ scattering, inelastic cross sections to the excited states in the $K^{π} = 0_{1}^{+}$ ground-, $K^{π} = 2^{+}$ side-, $K^{π} = 0_{2}^{+}$ cluster-, and $K^{π} = 1^{-}$ cluster-bands are investigated. The isospin characters of excitations are investigated via inelastic scattering processes by comparison of the production rates in the $^{10}$ Be+ $p$ , $^{10}$ Be+ $α$ , and $^{10}$ C+ $p$ reactions. The result predicts that the $2_{2}^{+}$ state is selectively produced by the $^{10}$ Be+ $p$ reaction because of the neutron dominance in the $2_{2}^{+}$ excitation as in the case of the $^{26}$ Mg+ $p$ scattering to the $2_{2}^{+}$ state, whereas its production is significantly suppressed in the $^{10}$ C+ $p$ reaction.
Comments:
19 pages, 12 figures
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2004.04936 [pdf]
PRC(2020)·13 citations
03
[Submitted on 10 Apr 2020]
Structure functions generated by zero sound excitations
V. A. Sadovnikova (St. Petersburg, INP)
In isospin symmetric and asymmetric nuclear matter we study the structure functions connected with the zero sound excitations. In the simple model with Landau-Migdal quasiparticle interactions the density response $Π^{R} (ω, k)$ of the nuclear matter to the small isovector external field $V_{0} (ω, k)$ is considered. In the previous papers the complex branches of solutions $ω_{s i} (k)$ , $i = n, p, n p$ of the dispersion equation corresponding to zero sound excitations in the symmetric and asymmetric nuclear matter are obtained. Now we investigate the structure and response functions of nuclear matter based on these solutions.
Comments:
14 pages, 3 figures, corrected misprint
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2004.04971 [pdf]
1 citation
04
[Submitted on 8 Apr 2020] (cross-list from quant-ph)
Hybrid Quantum Annealing via Molecular Dynamics
Hirotaka Irie🇯🇵 · Haozhao Liang🇯🇵 · Takumi Doi🇯🇵 · Shinya Gongyo🇯🇵 · Tetsuo Hatsuda🇯🇵
A novel quantum-classical hybrid scheme is proposed to efficiently solve large-scale combinatorial optimization problems. The key concept is to introduce a Hamiltonian dynamics of the classical flux variables associated with the quantum spins of the transverse-field Ising model. Molecular dynamics of the classical fluxes can be used as a powerful preconditioner to sort out the frozen and ambivalent spins for quantum annealers. The performance and accuracy of our smooth hybridization in comparison to the standard classical algorithms (the tabu search and the simulated annealing) are demonstrated by employing the MAX-CUT and Ising spin-glass problems.
Comments:
14 pages, 10 figures; v2: 17 pages, 14 figures, supplementary note added, to be published in Scientific Reports
Subjects:
Quantum Physics (quant-ph); Statistical Mechanics (cond-mat.stat-mech); High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th); Computational Physics (physics.comp-ph)
arXiv:
2004.03972 [pdf]
Sci.Rep.(2021)·30 citations
05
[Submitted on 10 Apr 2020] (cross-list from quant-ph)
Spectral density estimation with the Gaussian Integral Transform
Alessandro Roggero
The spectral density operator $ρ^(ω) = δ (ω - H^)$ plays a central role in linear response theory as its expectation value, the dynamical response function, can be used to compute scattering cross-sections. In this work, we describe a near optimal quantum algorithm providing an approximation to the spectral density with energy resolution $Δ$ and error $ϵ$ using $O (lo g (1/ ϵ) (lo g (1/Δ) + lo g (1/ ϵ)) /Δ)$ operations. This is achieved without using expensive approximations to the time-evolution operator but exploiting instead qubitization to implement an approximate Gaussian Integral Transform (GIT) of the spectral density. We also describe appropriate error metrics to assess the quality of spectral function approximations more generally.
Comments:
12 pages - published version
Subjects:
Quantum Physics (quant-ph); Nuclear Theory (nucl-th)
arXiv:
2004.04889 [pdf]
PRA(2020)·47 citations
06
[Submitted on 10 Apr 2020] (cross-list from cond-mat.quant-gas)
Emergence of a pseudogap in the BCS-BEC crossover
Adam Richie-Halford · Joaquín E. Drut · Aurel Bulgac
Strongly correlated Fermi systems with pairing interactions become superfluid below a critical temperature $T_{c}$ . The extent to which such pairing correlations alter the behavior of the liquid at temperatures $T > T_{c}$ is a subtle issue that remains an area of debate, in particular regarding the appearance of the so-called pseudogap in the BCS-BEC crossover of unpolarized spin- $1/2$ nonrelativistic matter. To shed light on this, we extract several quantities of crucial importance at and around the unitary limit, namely: the odd-even staggering of the total energy, the spin susceptibility, the pairing correlation function, the condensate fraction, and the critical temperature $T_{c}$ , using a non-perturbative, constrained-ensemble quantum Monte Carlo algorithm.
Comments:
6 pages (including references), 4 figures; Added Journal Reference
Subjects:
Quantum Gases (cond-mat.quant-gas); Superconductivity (cond-mat.supr-con); Nuclear Theory (nucl-th)
arXiv:
2004.05014 [pdf]
PRL(2020)·29 citations

Affiliations

first authorsco-authorsvia INSPIRE

Constraints on the neutron drip-line with the newly observed 39Na

Neutron dominance in excited states of 26Mg and 10Be probed by proton and alpha inelastic scattering

Structure functions generated by zero sound excitations

Hybrid Quantum Annealing via Molecular Dynamics

Spectral density estimation with the Gaussian Integral Transform

Emergence of a pseudogap in the BCS-BEC crossover

Affiliations

Neutron dominance in excited states of $^{26}$ Mg and $^{10}$ Be probed by proton and alpha inelastic scattering