Nuclear Theory·nucl-th

Tuesday·May 30, 2023

9 papers—7 primary·2 cross-listed

01
QCD-based charge symmetry breaking interaction and the Okamoto-Nolen-Schiffer anomaly
Hiroyuki Sagawa🇯🇵 · Tomoya Naito🇯🇵 · Xavier Roca-Maza🇮🇹 · Tetsuo Hatsuda🇯🇵
An approach is proposed to link the charge symmetry breaking (CSB) nuclear interaction and the low-energy constants in quantum chromodynamics (QCD) by matching the CSB effect in nuclear matter. The resulting CSB interaction is applied to study the Okamoto-Nolen-Schiffer anomaly, still lacking a satisfactory microscopic understanding, on the energy differences of mirror nuclei by taking $^{17} F$ - $^{17} O$ , $^{15} O$ - $^{15} N$ , $^{41} Sc$ - $^{41} Ca$ , and $^{39} Ca$ - $^{39} K$ as typical examples. The magnitude and sign of the QCD-based CSB interactions are found to resolve the anomaly successfully within theoretical uncertainties.
nucl-thhep-lathep-phnucl-exPRC(2024)·11 citations
02
Signatures for shape coexistence and shape/phase transitions in even-even nuclei
Dennis Bonatsos · Andriana Martinou · S.K. Peroulis · T.J. Mertzimekis · N. Minkov
Systematics of B(E2) transition rates connecting the first excited 0+ state to the first excited 2+ state of the ground state band in even-even nuclei indicates that shape coexistence of the ground state band and the first excited K=0 band should be expected in nuclei lying within the stripes of nucleon numbers 7-8, 17-20, 34-40, 59-70, 96-112 predicted by the dual shell mechanism of the proxy-SU(3) model, avoiding their junctions, within which high deformation is expected. Systematics of the excitation energies of the first excited 0+ states in even-even nuclei show that shape coexistence due to proton-induced neutron particle-hole excitations is related to a first-order shape/phase transition from spherical to deformed shapes, while shape coexistence due to neutron-induced proton particle-hole excitations is observed along major proton shell closures.
nucl-thJ.Phys.G(2023)·27 citations
03
The asymptotic behaviour of the many-body coupled cluster amplitudes
Saar Beck · Ronen Weiss · Nir Barnea
We analyze the asymptotic behaviour of the coupled cluster many-body wave-function in the limit of highly excited two- and three-particles states. We find that in this limit the different coupled cluster amplitudes exhibit a recurring behaviour, factorizing into a common asymptotic two- or three-body term. These asymptotic terms depend on the potential and in general are system specific. We also suggest that the knowledge of the asymptotic behaviour can potentially help solving the coupled cluster equations in a more efficient way.
nucl-thnucl-ex0 citations
04
Cluster model of 12C in density functional theory framework
A.S. Umar · K. Godbey · C. Simenel
We employ the constrained density functional theory to investigate cluster phenomena for the $^{12}$ C nucleus. The proton and neutron densities are generated from the placement of three $^{4}$ He nuclei (alpha particles) geometrically. These densities are then used in a density constrained Hartree-Fock calculation that produces an antisymmetrized state with the same densities through energy minimization. In the calculations no \textit{a priori} analytic form for the single-particle states is assumed and the full energy density functional is utilized. The geometrical scan of the energy landscape provides the ground state of $^{12}$ C as an equilateral triangular configuration of three alphas with molecular bond like structures. The use of the nucleon localization function provides further insight to these configurations. One can conclude that these configurations are a hybrid between a pure mean-field and a pure alpha particle condensate. This development could facilitate DFT based fusion calculations with a more realistic $^{12}$ C ground state.
nucl-thPRC(2023)·10 citations
05
A schematic model for the direct cross-section in reactions induced by exotic and stable projectiles
A.Serra · R.Lichtenthäler · O.C.B. Santos · K.C.C. Pires · U. Umbelino
A geometric model for the direct contribution of the reaction cross section induced by light ions on different targets is presented. The model separates the total reaction cross section into two components, one for total fusion and another for direct reactions. We show that the direct part scales as $2 π R a$ , where $R$ is related to the nuclear radius and $a$ is the width of a ring, which is related to the nuclear diffuseness. A simple expression is presented to calculate the radius $R$ and the width parameter $a$ in terms of the masses and charges of the system. The method is applied to experimental data of exotic, weakly bound, and strongly bound projectiles on several targets. Different diffuseness parameters were obtained for different types of projectiles: exotic n-rich, stable weakly bound, stable strongly bound and exotic p-rich exotic projectiles.
nucl-thnucl-ex0 citations
06
Studying the Impact of Virtuality-Dependent Nucleon Structure Modification on Spectator-Tagged Deep Inelastic Scattering
Sara Ratliff🇺🇸 · Axel Schmidt🇺🇸
Measurements of deep inelastic scattering from nuclei have revealed that the partonic structure of bound nucleons differs from that of free nucleons. One hypothesis is that this structure modification primarily occurs in highly virtual nucleons participating in short-range correlations, although distinguishing this from other hypotheses is difficult with inclusive measurements alone. Spectator-tagged deep inelastic scattering, on the other hand, may offer a way to specifically probe the partonic structure of highly-virtual nucleons by detecting the correlated emission of a spectator nucleon. Here, we present a method for calculating a "spectator-tagged" structure function for a nucleus by combining Generalized Contact Formalism's description of short-range correlations with light-cone convolution formalism to determine the impact of nucleon motion on the structure function. We apply this method to calculate predictions for helium-4, and find that differences in the virtuality-dependence of nucleon structure modification can lead to large measurable changes in the tagged structure function. The recent CLAS12 Short-Range Correlations Experiment, which collected electron scattering data on helium-4 and other nuclear targets, may be able to constrain this virtuality-dependence and help test whether correlations are the origin of the modification of bound nucleon structure.
nucl-thEPJA(2024)·2 citations
07
The European Muon Collaboration effect from short-range correlated nucleons in a nucleon swelling model
Na-Na Ma🇨🇳 · Tao-Feng Wang🇨🇳 · Rong Wang🇨🇳
The relation between the nuclear EMC effect and the nucleon-nucleon short-range correlation is a hot topic in high-energy nuclear physics, ever since a peculiar linear correlation between these two phenomena discovered. In this paper, the contribution to the nuclear EMC effect arising from the short-range correlated nucleons is examined in a nucleon-swelling model. We find that the structure modifications of the N-N SRC nucleons reproduce more or less the measured EMC ratios of light nuclei, while they are not enough to explain the measured EMC ratios of heavy nuclei. We speculate that the hypothesis of causal connection between SRC and the EMC effect is not exact, or the universality of the inner structure of SRC nucleon is violated noticeably from light to heavy nuclei, or there are other origins for the EMC effect.
nucl-thPRC(2023)·5 citations
08
Vector meson effects on the multi-skyrmion states from the rational map ansatz
Jun-Shuai Wang🇨🇳 · Yong-Liang Ma🇨🇳
The roles of the lightest vector mesons $ρ$ and $ω$ in the multi-skyrmion states are studied using the hidden local symmetry approach upto the next to leading order including the homogeneous Wess-Zumino terms. The low energy constants in the effective field theory are determined by using the Sakai-Sugimoto model and the flat-space five-dimensional Yang-Mills action. With only two inputs, $m_{ρ}$ , and $f_{π}$ , all the low energy constants can be determined without ambiguity. The vector meson effects can be investigated by integrating them in order and the influence from the geometry can be clarified by comparing the results using the low energy constants estimated from the Sakai-Sugimoto model and the flat-space five-dimensional Yang-Mills action. We find that the $ρ$ meson reduces the masses of the multi-skyrmion states and increases the overlaps of the constituents of the multi-skyrmion states while the $ω$ meson repulses the constituents of the multi-skyrmion states and increases their masses, therefore these vector mesons are important in Skyrme model approach to nuclei. we also find that the warping factor which is an essential element in the holographic model of QCD affects the properties of the multi-skyrmion states and cannot be ignored.
↳ hep-phhep-thnucl-thSCPMA(2023)·1 citation
09
Bottomonium suppression at RHIC and LHC in an open quantum system approach
Michael Strickland🇺🇸 · Sabin Thapa🇺🇸
We present potential non-relativistic quantum chromodynamics (pNRQCD) predictions for bottomonium suppression in sqrt(sNN) = 200 GeV, 2.76 TeV, and 5.02 TeV heavy-ion collisions using an open quantum systems (OQS) description of the reduced heavy-quark anti-quark density matrix. Compared to prior OQS+pNRQCD studies we include the rapidity dependence of bottomonium production and evolution, allowing for a fully 3-dimensional description of bottomonium trajectories in the quark-gluon plasma. The underlying formalism used to compute the ground and excited state survival probabilities is based on a Lindblad equation that is accurate to next-to-leading order (NLO) in the binding energy over temperature. For the background evolution, we make use of a 3+1D viscous hydrodynamics code which reproduces soft hadron observables at all three collision energies. We find good agreement between NLO OQS+pNRQCD predictions and data taken at LHC energies, however, at RHIC energies, there is tension with recent bottomonium suppression measurements by the STAR collaboration.
↳ hep-phnucl-thPRD(2023)·8 citations

Affiliations

first authorsco-authorsvia INSPIRE