Nuclear Theory·nucl-th

Thursday·February 22, 2024

15 papers—8 primary·7 cross-listed

01
[Submitted on 20 Feb 2024]
Behavior of the continuum coupling correlation energy in the vicinity of the particle emission threshold -- Gamow shell model study
J. P. Linares Fernandez🇺🇸 · N. Michel🇨🇳 · M. Płoszajczak🇫🇷
The Gamow shell model provides the open quantum system formulation of nuclear shell model. In the coupled-channel representation, Gamow shell model provides the unified theory of nuclear structure and reactions which is well suited for the study of resonances and clusterization. In this work, we apply this approach to study the continuum-coupling correlation energy for selected near-threshold states of $^{7}$ Li, $^{7}$ Be, using a translationally invariant Hamiltonian with an effective finite-range two-body interaction.
Comments:
10 pages, 4 figures. Presented at the 45th Symposium on Nuclear Physics at Cocoyoc, Morelos, Mexico. arXiv admin note: text overlap with arXiv:2306.05215
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2402.13305 [pdf]
EPJ Web Conf.(2024)·0 citations
02
[Submitted on 20 Feb 2024]
Spin-Triplet Pairing in Heavy Nuclei is Stable Against Deformation
G. Palkanoglou · M. Stuck · A. Gezerlis
Any experimental evidence of nucleons paired in spin-triplet states will confirm the existence of an exotic phase of nuclear matter. This type of nuclear superfluidity has been hypothesized in heavy nuclei, where the antagonizing spin-orbit effects are damped, and there it oftentimes coexists with traditional spin-singlet pairing, leading to the possibility of mixed-spin pairing. Realistic nuclear deformation, not considered in such studies, could make-or-break these proposals, since its effect on triplet-pairing, and the competition (and coexistence) of the two superfluid phases, was expected to be crucial. We report on a thorough study on the effect of deformation on triplet-, singlet-, and mixed-spin pairing in the relevant region of the nuclear chart. We find that, at low isospin asymmetries, spin-triplet pairing is enhanced by deformation, while below the proton-drip line, the novel superfluid phase survives alongside the usual spin-singlet pairing. These results suggest that spin-triplet superfluidity exists in realistic nuclei and can be probed in the lab.
Comments:
6 pages, 3 figures; v2 corresponds to published version
Subjects:
Nuclear Theory (nucl-th); Superconductivity (cond-mat.supr-con)
arXiv:
2402.13313 [pdf]
PRL(2025)·13 citations
03
[Submitted on 20 Feb 2024]
Low-energy dipole strength in 8He
Francesca Bonaiti · Sonia Bacca
In this work, we present new ab initio coupled-cluster calculations of dipole-excited state properties of 8He based on the chiral effective field theory interaction 1.8/2.0 (EM). We focus on the dipole polarizability, and compare the results to our previous study [Phys. Rev. C 105, 034313 (2022)] and subsequent theoretical work. With the aim of connecting the presence of low-lying dipole strength to structure properties of 8He, we compute the point-neutron radius, finding excellent agreement with available experimental data, and investigate its correlation with the dipole polarizability.
Comments:
13 pages including references, 2 figures, submitted to Few-Body Systems as contribution to Special Issue "Advances on the Few-Body Problem in Physics - Selected and refereed papers from the 25th European Conference"
Subjects:
Nuclear Theory (nucl-th); Nuclear Experiment (nucl-ex)
arXiv:
2402.13323 [pdf]
Few Body Syst.(2024)·5 citations
04
[Submitted on 20 Feb 2024]
Double Scattering in Deuteron Electrodisintegration
Werner U Boeglin🇺🇸 · Misak M Sargsian🇺🇸
We demonstrate that at sufficiently high energies where the eikonal regime is established for hadronic interactions, the double scattering subprocess can be clearly identified and isolated in quasi-elastic deuteron electro-disintegration processes. Comparing theoretical calculations with the recent high precision experimental data we present a ``proof of principle" that these processes can be used to study advanced issues related to hadron formation in QCD. In this case, the double scattering represents as a fermi-scale ``detector" which probes products of high $Q^{2}$ scattering from the bound nucleon through their rescattering from the spectator nucleon in the deuteron.
Comments:
10 pages, 11 figures
Subjects:
Nuclear Theory (nucl-th); Nuclear Experiment (nucl-ex)
arXiv:
2402.13411 [pdf]
PLB(2024)·5 citations
05
[Submitted on 21 Feb 2024]
Non-nucleonic degrees of freedom and the spin structure of the deuteron
Misak M Sargsian🇺🇸
Electro-disintegration of the deuteron at large $Q^{2}$ currently represents on of the most promising reactions which allows to probe the bound nuclear state at internal momenta comparable to the rest mass of the nucleon. Large internal momentum in this case makes non-nuncleonic states energetically more feasible and the question that we address is what are the signatures that will indicate the existence of such states in the ground state of the nuclear wave function. To probe such states we developed a light-front formalism for relativistic description of a composite pseudo-vector system in which emerging proton and neutron are observed in electro-disintegration reaction. In leading high energy approximation our calculations show the possibility of the existence of a new ``incomplete" P-state-like structure in the deuteron at extremely large internal momenta. The incompleteness of the observed P-state violates the angular condition for the momentum distribution, which can happen only if the deuteron contains non-nucleonic structures, such as $ΔΔ$ , $N^{*} N$ or hidden color components. Because such states have distinctive angular momentum ( $l = 1$ ) they significantly modify the polarization properties of the deuteron wave function. As a result in addition to angular anisotropy of the LF momentum distribution of the nucleon in the deuteron one predicts strong modification of the tensor polarization asymmetry of the deuteron beyond the S- and D- wave predictions at large internal momenta in the deuteron.
Comments:
Ten pages, two figures, Proceedings for 25th International Spin Physics Symposium (SPIN 2023), 24-29 September 2023, Durham, NC, USA. arXiv admin note: text overlap with arXiv:2208.00501
Subjects:
Nuclear Theory (nucl-th); High Energy Physics — Phenomenology (hep-ph); Nuclear Experiment (nucl-ex)
arXiv:
2402.13458 [pdf]
PoS(2024)·0 citations
06
[Submitted on 21 Feb 2024]
Kaon production in the HADES experiment in Au+Au collisions at $s_{NN} = 2.4$ GeV
Gao-Feng Wei🇨🇳 · Yu-Liang Zhao🇨🇳
Within an isospin- and momentum-dependent transport model by including the kaon reaction channels, we study the kaon prodution in heavy-ion collisions (HICs) at SIS (Darmstadt Schwerionen Synchrotron, GSI) energies. Based on simulations of a centrality of 0-40% Au + Au collision at $s_{N N} = 2.4$ GeV, a typical reaction that has been carried out by the HADES Collaboration, we confirm that the medium modification of kaon masses plays a vital role in studying the kaon productions in HICs, and is also unavoidable for the successful interpretation of the HADES data on kaon rapidity distributions and transverse mass spectra. Moreover, it is shown that the directed flows of kaons are affected significantly by the kaon potential and slightly affected by the medium modification of kaon masses. Also, the rapidity-dependent inverse slope parameter $T_{B}$ of the kaon transverse mass spectra is shown to be affected considerably by both the kaon potential and medium modification of kaon masses. However, through checking the simulations of related reactions in FOPI and/or KaoS experiments, some of these regular effects do not seem to be obvious and appear to be the reaction system and/or beam energy dependent. Nevertheless, it can be confirmed that the medium modification of kaon masses is favored by observations from the inverse slope parameter $T_{B}$ and transverse mass spectra of kaons in both HADES Au + Au collisions at $s_{N N} = 2.4$ GeV and FOPI Ni + Ni collisions at 1.93\textit{A} GeV. Therefore, measurements of the inverse slope parameter $T_{B}$ of kaon transverse mass spectra and the kaon directed flows in HADES Au + Au collisions would be great benefit to detection of the kaon potential and the corresponding medium effects on kaon masses.
Comments:
12 pages, 9 figures, more results and figures are included. Accepted for publication in Physical Review C
Subjects:
Nuclear Theory (nucl-th); Nuclear Experiment (nucl-ex)
arXiv:
2402.13570 [pdf]
PRC(2024)·3 citations
07
[Submitted on 21 Feb 2024]
Theoretical analysis and predictions for the double electron capture of $^{124}$ Xe
Ovidiu Niţescu🇸🇰 · Stefan Ghinescu🇷🇴 · Vasile-Alin Sevestrean🇷🇴 · Mihai Horoi🇷🇴 · Fedor Šimkovic🇸🇰 · Sabin Stoica🇷🇴
We provide a complete theoretical description of the two-neutrino electron capture in $^{124}$ Xe, improving both the nuclear and the atomic structure calculations. We improve the general formalism through the use of the Taylor expansion method, leading to higher order terms in the decay rate of the process. The nuclear part is treated with pn-QRPA and interacting shell model (ISM) methods. The nuclear matrix elements (NMEs) are calculated with the pn-QRPA method with spin restoration by fixing the input parameters so that the experimental decay rate is reproduced, resulting in values significantly lower than in previous calculations. The validity of the pn-QRPA NMEs is tested by showing their values to be comparable with the ones for double-beta decay with emission of two electrons of $^{128, 130}$ Te, which have similar pairing features. Within the ISM, we reproduce the total experimental half-life within a factor of two and predict the capture fraction to the KK channel of about 74\%. We also predict the capture fractions to other decay channels and show that for the cumulative decay to the $K L_{1}$ - $K O_{1}$ channels, a capture fraction of about 24\% could be observed experimentally. On the atomic side, calculations are improved by accounting for the Pauli blocking of the decay of innermost nucleon states and by considering all $s$ -wave electrons available for capture, expanding beyond the K and L $_{1}$ orbitals considered in previous studies. We also provide improved atomic relaxation energies of the final atomic states of $^{124}$ Te, which may be used as input for background modeling in liquid Xenon experiments.
Comments:
9 pages, 2 figures
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2402.13784 [pdf]
J.Phys.G(2024)·15 citations
08
[Submitted on 21 Feb 2024]
Uncovering the sign of nuclear deformations: Determination of prolate or oblate shape via low-energy $α$ inelastic scattering
Shin Watanabe · Yoshiki Suzuki · Masaaki Kimura · Kazuyuki Ogata
Background: Understanding nuclear shape is a crucial problem in nuclear physics. In particular, determining the sign of quadrupole deformation, i.e., whether prolate or oblate, remains a challenging problem. Purpose: Our aim is to propose a method for determining the sign of quadrupole deformation using $α$ inelastic scattering data and to demonstrate its effectiveness. Method: Our approach is the standard coupled-channel method based on the macroscopic model. We utilize the nuclear reorientation effect, a phenomenon associated with the self coupling of excited states, as a probe sensitive to the sign of deformation. Results: We first provide an overview of how the reorientation effect influences inelastic scattering cross sections, and numerically confirm its validity in realistic cases. We then demonstrate that the sign of deformation can be uniquely determined from inelastic scattering cross section data. Conclusion: Our technique offers a systematic approach for determining the sign of deformation in both stable and unstable nuclei. The broad applicability of $α$ inelastic scattering will make it a valuable tool to study shape of nuclei, especially unstable nuclei.
Comments:
7 pages, 8 figures
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2402.13832 [pdf]
PRC(2024)·0 citations
09
[Submitted on 18 Feb 2024] (cross-list from hep-ph)
Transversity generalized parton distributions in spin-3/2 particles
Dongyan Fu🇨🇳 · Yubing Dong🇨🇳 · S. Kumano🇯🇵
The definitions of the quark and gluon transversity generalized parton distributions (GPDs) in spin-3/2 particles are obtained in the light-cone gauge. It is found that they contain 16 independent components for each parton. Their even or odd property is found in terms of skewness variable, and the odd transversity GPDs vanish in the forward limit. There are 16 amplitudes with helicity flip of quark or gluon. We conclude that all the amplitudes, unpolarized, polarized, and transversity amplitudes, have a common factor $F (ζ)$ carrying all the complex part. Here, the variable $ζ$ is the helicity difference $ζ = (λ^{'} - λ) - (μ^{'} - μ)$ for the amplitude $A_{λ^{'} μ^{'}, λ μ}$ . This kinematical factor is associated with the transfer of the orbital angular momentum in the quark- and gluon-spin-3/2 particle scattering amplitudes. We also derive another main physical quantity, transversity distribution, from the transversity GPDs in the forward limit for the spin-3/2 particles.
Comments:
22 pages, 2 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); High Energy Physics — Lattice (hep-lat); Nuclear Theory (nucl-th)
arXiv:
2402.11561 [pdf]
PRD(2024)·8 citations
10
[Submitted on 20 Feb 2024] (cross-list from hep-ph)
Renormalization of beta decay at three loops and beyond
Kaushik Borah🇺🇸 · Richard J. Hill🇺🇸 · Ryan Plestid🇺🇸
The anomalous dimension for heavy-heavy-light effective theory operators describing nuclear beta decay is computed through three-loop order in the static limit. The result at order $Z^{2} α^{3}$ corrects a previous result in the literature. An all-orders symmetry is shown to relate the anomalous dimensions at leading and subleading powers of $Z$ at a given order of $α$ . The first unknown coefficient for the anomalous dimension now appears at $O (Z^{2} α^{4})$ .
Comments:
Matches journal version. Small typos fixed
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2402.13307 [pdf]
PRD(2024)·16 citations
11
[Submitted on 20 Feb 2024] (cross-list from nucl-ex)
Giant Dipole Resonance photofission and photoneutron reactions in $^{238}$ U and $^{232}$ Th
D. Filipescu · I. Gheorghe · S. Goriely · A. Tudora · K. Nishio · T. Ohtsuki · H. Wang · G. Fan · K. Stopani · F. Suzaki · K. Hirose · M. Inagaki and 5 other authors
New measurements of photofission and photoneutron reactions on $^{238}$ U and $^{232}$ Th in the Giant Dipole Resonance (GDR) energy region have been performed at the laser Compton-scattering $γ$ -ray source of the NewSUBARU synchrotron radiation facility using a high-and-flat efficiency moderated $^{3}$ He detection array. The neutron-multiplicity sorting of high-multiplicity fission neutron coincidence events has been performed using a dedicated energy dependent, multiple firing statistical treatment. The photoneutron $(γ, in)$ with $i$ ~=~1~--~3 and photofission $(γ, F)$ reactions have been discriminated by considering a Gaussian distribution of prompt-fission-neutron (PFN) multiplicities predicted by the theory of evaporation in sequential neutron emission from excited fission fragments. We report experimental $(γ, n)$ , $(γ, 2 n)$ , $(γ, 3 n)$ and $(γ, F)$ cross sections, average energies of PFNs and of $(γ, in)$ photoneutrons, as well as the mean number of PFNs per fission act and the width of the PFNs multiplicity distribution. Based on these primary experimental results and combined with reasonable assumptions, we extract also the first- and second-chance fission contributions. The new experimental results are compared with statistical-model calculations performed with the EMPIRE-3.2 Malta and TALYS-1.964 codes on the present data and with prompt fission emission calculations obtained with the Los Alamos model in the frame of the most probable fragmentation approach with and without sequential emission.
Subjects:
Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2402.13333 [pdf]
PRC(2024)·8 citations
12
[Submitted on 21 Feb 2024] (cross-list from hep-ph)
Pion-nucleus elastic scatterings incorporating medium effects within the Eikonal-Glauber mode
Hyeon-dong Han🇰🇷 · Parada T. P. Hutauruk🇰🇷 · Seung-il Nam🇰🇷
In this present investigation, we explore the elastic scattering of pions with nuclei ( $π$ - $A$ ), primarily influenced by the $Δ$ (1232) resonance, within the Eikonal-Glauber model. The medium effects are incorporated by considering nuclear-density ( $ρ_{A}$ ) dependent masses of baryons and strong coupling constants. These dependencies are computed and parameterized up to $O (ρ_{A}^{2})$ based on the quark-meson coupling (QMC) model. The Wood-Saxon type density profile is utilized for the bound nucleons within finite nuclei. The element $π^{+}$ - $N$ scattering cross section for the Glauber approach is determined using the conventional effective Lagrangian method. Subsequently, we analyze the total cross sections for elastic scattering with $^{4}$ He and $^{12}$ C targets. Our numerical results demonstrate a favorable agreement with JINR data for the $^{4}$ He target, accurately reproducing the total cross-section. However, when considering the $^{12}$ C target, deviations of approximately $≲ 10%$ . We also consider the multiple-scattering effects inside the nucleus approximately, using the single-channel meson-baryon Bethe-Salpeter equation, resulting in the effective width broadening of the $Δ$ resonance to reproduce the data better.
Comments:
8 pages, 4 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2402.13526 [pdf]
J.Korean Phys.Soc.(2024)·1 citation
13
[Submitted on 21 Feb 2024] (cross-list from hep-ph)
Estimating the dark matter halo velocity and surface temperature of some known pulsars due to dark matter capture
Debashree Sen · Atanu Guha
Considering four known pulsars J1906+0746, J1933-6211, J2043+1711 and the Vela pulsar, we study the scenario of dark matter (DM) capture in neutron stars (NSs). For the purpose we choose four well-known relativistic mean field models to obtain the radius corresponding to the observed mass of these pulsars and consequently the scattering cross-section of DM with the different particles of the $β$ stable NS matter. The estimated DM-electron scattering cross-section in this work is stringent compared to the current direct detection experimental probe. We then compute the lower limit on the halo velocity of DM for the four pulsars from the knowledge of the upper limit on effective temperature of the individual pulsars. We also extend our work to calculate the value of the effective temperature with the different models using the fitted values of the halo velocity of DM of the four pulsars with respect to their distances from the galactic center. Our findings are consistent with the analysis of the observed data.
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Astrophysical Phenomena (astro-ph.HE); Nuclear Theory (nucl-th)
arXiv:
2402.13795 [pdf]
3 citations
14
[Submitted on 21 Feb 2024] (cross-list from physics.chem-ph)
Reference Energies for Valence Ionizations and Satellite Transitions
Antoine Marie · Pierre-François Loos
Upon ionization of an atom or a molecule, another electron (or more) can be simultaneously excited. These concurrently generated states are called "satellites" (or shake-up transitions) as they appear in ionization spectra as higher-energy peaks with weaker intensity and larger width than the main peaks associated with single-particle ionizations. Satellites, which correspond to electronically excited states of the cationic species, are notoriously challenging to model using conventional single-reference methods due to their high excitation degree compared to the neutral reference state. This work reports 42 satellite transition energies and 58 valence ionization potentials of full configuration interaction (FCI) quality computed in small molecular systems. Following the protocol developed for the quest database [https://doi.org/10.1002/wcms.1517, Véril et al. Wiley Interdiscip. Rev.: Comput. Mol. Sci. 2021, 11, e1517], these reference energies are computed using the configuration interaction using a perturbative selection made iteratively (CIPSI) method. In addition, the accuracy of the well-known coupled-cluster (CC) hierarchy (CC2, CCSD, CC3, CCSDT, CC4, and CCSDTQ) is gauged against these new accurate references. The performances of various approximations based on many-body Green's functions ( $G W$ , GF2, and $T$ -matrix) for ionization potentials are also analyzed. Their limitations in correctly modeling satellite transitions are discussed.
Comments:
22 pages, 3 figures (supporting information available)
Subjects:
physics.chem-ph (physics.chem-ph); cond-mat.mtrl-sci (cond-mat.mtrl-sci); Nuclear Theory (nucl-th)
arXiv:
2402.13877 [pdf]
J.Chem.Theor.Comput.(2024)·13 citations
15
[Submitted on 21 Feb 2024] (cross-list from quant-ph)
Partial-transpose-guided entanglement classes and minimum noise filtering in many-body Gaussian quantum systems
Boyu Gao🇺🇸 · Natalie Klco🇺🇸
The reduction and distortion of quantum correlations in the presence of classical noise leads to varied levels of inefficiency in the availability of entanglement as a resource for quantum information processing protocols. While generically minimizing required entanglement for mixed quantum states remains challenging, a class of many-body Gaussian quantum states ( $N$ IC) is here identified that exhibits two-mode bipartite entanglement structure, resembling that of pure states, for which the logarithmic negativity entanglement measure remains invariant upon inclusion of the classical correlations and optimal entanglement resources can be clearly quantified. This subclass is found to be embedded within a broader class of many-body Gaussian states ( $N$ -SOL) that retain two-mode entanglement structure for detection processes. These two entanglement classes are relevant in theoretical and experimental applications from the scalar field vacuum to the local axial motional modes of trapped ion chains. Utilizing the subspace that heralds inseparability in response to partial transposition, a minimum noise filtering process is designed to be necessary, sufficient, and computable for determining membership in these classes of entanglement structure. Application of this process to spacelike regions of the free scalar field vacuum is found to improve resource upper bounds, providing new understanding of the entanglement required for the quantum simulation of quantum fields as observed by arrays of local detectors.
Comments:
11 pages, 2 figures, 4 appendices
Subjects:
Quantum Physics (quant-ph); High Energy Physics — Lattice (hep-lat); Nuclear Theory (nucl-th)
arXiv:
2402.13881 [pdf]
PRA(2024)·7 citations

Affiliations

first authorsco-authorsvia INSPIRE