PaperPanorama
FAQ

Nuclear Theory·nucl-th

Friday·December 9, 2022

6 papers—5 primary·1 cross-listed

All6Primary5Cross-lists1
  1. 01

    Alpha decay of thermally excited nuclei

    J. E. Perez Velasquez · O. L. Caballero · N. G. Kelkar

    One of the prominent decay modes of heavy nuclei which are produced in astrophysical environments at temperatures of the order of K is the (He) decay. Thermally enhanced decay rates are evaluated within the standard scheme of a tunneling decay where the particle tunnels through the potential barrier formed by its interaction with the daughter nucleus. Following the observation that there exist several excited levels with the possibility of an decay when the daughter nucleus is at a shell closure, we focus in particular on decays producing daughter nuclei with the neutron number, N = 126. Within a statistical approach we find that the half-lives, , for temperatures ranging from = 0 to 2.4 GK can decrease by 1 - 2 orders of magnitude with the exception of the decay of Po which decays to the doubly magic daughter Pb, where decreases by 5 orders of magnitude. The effect of these thermally enhanced decays on the -process nucleosynthesis can be significant in view of the mass build up at the waiting point nuclei with closed neutron shells.

    nucl-thastro-ph.HEnucl-exJ.Phys.G(2023)·8 citations
  2. 02

    Revisiting the centrality definition and observable centrality dependence of relativistic heavy-ion collisions in PACIAE model

    Yu-Liang Yan🇨🇳 · Dai-Mei Zhou🇨🇳 · An-Ke Lei🇨🇳 · Xiao-Mei Li🇨🇳 · Xiao-Ming Zhang🇨🇳 · Liang Zheng🇨🇳 · Gang Chen🇨🇳 · Xu Cai🇨🇳 · Ben-hao Sa🇨🇳

    We improve the centrality definition in impact parameter in PACIAE model responding the fact reported by the ALICE, ATLAS, and CMS collaborations that the maximum impact parameter in heavy ion collisions should be extended to 20 . Meanwhile the PACIAE program is updated to a new version of PACIAE 2.2.2 with convenience of studying the elementary nuclear collisions, proton-nucleus collisions, and the nucleus-nucleus collisions in one unified program version. The new impact parameter definition together with the optical Glauber model calculated impact parameter bin, , and in proton-nucleus and nucleus-nucleus collisions at relativistic energies are consistent with the improved MC-Glauber model ones within the error bar. The charged-particle pseudorapidity and the transverse momentum distributions in Pb-Pb collisions at TeV simulated by PACIAE 2.2.2 well reproduce the ALICE experimental data.

    nucl-thhep-phComput.Phys.Commun.(2023)·4 citations
  3. 03

    Nuclear chiral rotation induced by superfluidity

    Y. P. Wang · J. Meng

    The microscopic understanding on the influence of the pairing correlations or the superfluidity on the nuclear chiral rotation has been a longstanding and challenging problem. Based on the three-dimensional cranking covariant density functional theory, a shell-model-like approach with exact particle number conservation is implemented to take into account the pairing correlations and applied for the chiral doublet bands in Nd135. The data available are well reproduced. It is found that the superfluidity can reduce the critical frequency and make the chiral rotation easier. The mechanism is that the particle/hole alignments along the short/long axis are reduced by the pairing correlations, resulting in the enhanced preference of the collective rotation along the intermediate axis, and inducing the early appearance of the chiral rotation.

    nucl-thnucl-exPLB(2023)·23 citations
  4. 04

    Symplectic symmetry and clustering in atomic nuclei

    H. G. Ganev

    A new symplectic-based shell-model approach to clustering in atomic nuclei is proposed by considering the simple system Ne. Its relation to the collective excitations of this system is mentioned as well. The construction of the Pauli allowed Hilbert space of the cluster states with maximal permutational symmetry is given for the O+He Ne channel in the case of one-component many-particle nuclear system. The equivalence of the obtained cluster model space to that of the semi-microscopic algebraic cluster model is demonstrated.

    nucl-thNucl.Phys.(2021)·1 citation
  5. 05

    Dilute neutron star matter from neural-network quantum states

    Bryce Fore · Jane M. Kim · Giuseppe Carleo · Morten Hjorth-Jensen · Alessandro Lovato

    Low-density neutron matter is characterized by fascinating emergent quantum phenomena, such as the formation of Cooper pairs and the onset of superfluidity. We model this density regime by capitalizing on the expressivity of the hidden-nucleon neural-network quantum states combined with variational Monte Carlo and stochastic reconfiguration techniques. Our approach is competitive with the auxiliary-field diffusion Monte Carlo method at a fraction of the computational cost. Using a leading-order pionless effective field theory Hamiltonian, we compute the energy per particle of infinite neutron matter and compare it with those obtained from highly realistic interactions. In addition, a comparison between the spin-singlet and triplet two-body distribution functions indicates the emergence pairing in the channel.

    nucl-thcond-mat.dis-nnquant-phPRResearch(2023)·29 citations

Affiliations

first authorsco-authorsvia INSPIRE