Nuclear Theory·nucl-th

Wednesday·July 19, 2023

17 papers—8 primary·9 cross-listed

01
[Submitted on 15 Jul 2023]
On the problems of creating a nuclear-optical frequency standard based on 229Th
F. F. Karpeshin · L. F. Vitushkin
The most probable candidate for the role of a nuclear optical standard is the 8.338-eV isomer of the 229mTh isotope of the thorium nucleus. Ways of using the resonance properties of the electron shell as an optical resonator to create laser-nuclear technologies necessary for the optical pumping of nuclear isomers and other manipulations of atomic nuclei leading to the creation of a next-generation frequency standard and nuclear-optical clocks based on them are discussed. Deep relations between the physics of resonance electron-nuclear interactions and the true solution of the thorium puzzle are shown. The article discusses important principles of resonant optical pumping, such as the presence of a finite width in the intermediate electronic state, and others that are usually overlooked with a fatal result for the experiment. The wide application of the various physics of these processes will predetermine a revolutionary leap in the development of new laser-nuclear technologies.
Comments:
9 pages, 3 figures, submitted to the Proceedings of KVNO-2023
Subjects:
Nuclear Theory (nucl-th); Nuclear Experiment (nucl-ex)
arXiv:
2307.08711 [pdf]
3 citations
02
[Submitted on 18 Jul 2023]
Proton 0.01 MeV resonance width and low-energy $S$ -factor of p+10B fusion
A. M. Mukhamedzhanov
{\bf{Purpose}:} In this paper, the proton resonance width of the near-threshold resonance is calculated using two different approaches. The values of the proton width are used to calculate the low-energy $S$ -factor. \\ {\bf{Method:}} First, the proton resonance width is estimated using the mirror symmetry of the resonance $^{11} C (E_{x} = 8.70 MeV; \frac{5}{2}^{+})$ and the mirror bound state $^{11} B (E_{x} = 9.272 MeV; \frac{5}{2}^{+})$ . In the second approach, this width is estimated using the $R$ -matrix definition of the observable resonance width, which is expressed in terms of the $p -^{10} B$ resonant wave function calculated in the potential approach and the spectroscopic factor. \\ {\bf{Results}:} Depending on the method chosen, the calculated proton resonance width varies from $1.03 \times 1 0^{- 19}$ MeV to $2.96 \times 1 0^{- 19}$ MeV. The role of the near-threshold resonance is determined using fitting of two low-energy $S$ -factors from direct measurements [C. Angulo {\it et al.}, Z. Phys. A {\bf 345}, 333 (1993)] and from the indirect Trojan horse method (THM) [ A. Cvetinović {\it et al.}, Phys. Rev. C {\bf 97}, 065801 (2018)]. Within the framework of the $R$ -matrix method using the determined proton resonance widths and the modified THM parameters for six low-lying resonances, the low-energy $S$ -factors were calculated and compared with the corresponding experimental $S$ -factors. The closest agreement with the data is achieved with the proton resonance widths $1.0 \times 1 0^{- 19}$ MeV when fitting the $S$ -factor from the THM indirect measurements, and $1.68 \times 1 0^{- 19}$ MeV and $2.5 \times 1 0^{- 19}$ MeV when fitting the $S$ -factor from [Angulo {\it et al}, Z. Phys. A {\bf 345}, 333 (1993)].\
Comments:
11 pages, 6 figures
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2307.08963 [pdf]
PRC(2023)·1 citation
03
[Submitted on 18 Jul 2023]
Postfission properties of uranium isotopes: A hybrid method with Langevin dynamics and the Hauser-Feshbach statistical model
Shyoya Tanaka · Nobuya Nishimura · Futoshi Minato · Yoshihiro Aritomo
Background: Precise understanding of nuclear fission is crucial for experimental and theoretical nuclear physics, astrophysics, and industrial applications; however, the complete physical mechanics is unresolved due to the complexities. Purpose: In this study, we present a new method to describe the dynamical-fission process and following prompt-neutron emission, where we combine the dynamical fission calculation based on the Langevin method and the Hauser-Feshbach statistical model. Methods: Two methods are connected smoothly within the universal charge distribution and the energy conservation, allowing us to calculate a sequence of fission dynamics and post-fission phase, including prompt neutron emission. Results: Using a certain set of model parameters, we successfully reproduce the experimental primary-fission yields, total kinetic energy, independent-fission yields, and prompt neutron emissions for the neutron induced fission of $^{236}$ U, a compound nucleus of $n +^{235} U$ . We elucidate the physical mechanism of the characteristic features observed in previous experiments, such as shell properties. Additionally, we apply our calculation to two very neutron-rich uranium isotopes, i.e., $^{250}$ U and $^{255}$ U, which are not experimentally confirmed but are important for r-process nucleosynthesis. Theoretical results indicate that $^{250}$ U exhibits an asymmetric multiple-peak fission yield distribution, while the neutron-rich $^{255}$ U has a single peak due to symmetric fission. Our method predicts post-neutron emission fragments, where $^{250}$ U shows a stronger neutron emissivity than $^{255}$ U. Conclusions: Our framework is highly reproducible in the experiments and shows that the number of emitted neutrons after fission differs significantly in neutron-rich uranium fission depending on distributions of fission variables.
Comments:
12 pages, 11 figures, published in PRC, minor revisions to match the final version
Subjects:
Nuclear Theory (nucl-th); High Energy Astrophysical Phenomena (astro-ph.HE); Nuclear Experiment (nucl-ex)
arXiv:
2307.08971 [pdf]
PRC(2023)·5 citations
04
[Submitted on 18 Jul 2023]
Effects of Symmetry Energy on the Equation of State for Hybrid Neutron Stars
Parada T. P. Hutauruk🇰🇷 · Hana Gil🇰🇷 · Seung-il Nam🇰🇷 · Chang Ho Hyun🇰🇷
In this paper, the implications of the symmetry energy on the hadron and quark phase transitions in the compact star, including the properties of the possible configurations of the quark-hadron hybrid stars, are investigated in the frameworks of the energy-density functional (EDF) models and the flavor SU(2) Nambu--Jona-Lasinio (NJL) model with the help of the Schwinger's covariant proper-time regularization (PTR) scheme. In this {theoretical setup}, the equations of states (EoSs) of hadronic matter for various values of symmetry energies obtained from the EDF models are employed to describe the hadronic matter, and the {flavor} SU(2) NJL model with various repulsive-vector interaction strengths are used to describe the quark matter. We then observe the obtained EoS in the mass-radius properties of the hybrid star configurations for various vector interactions and nuclear symmetry energies by solving the Tolman-Oppenheimer-Volkoff equation. We obtain that the critical density at which the phase transition occurs varies over the density (3.6--6.7) $ρ_{0}$ depending on the symmetry energy and the strength of the vector coupling $G_{v}$ . The maximum mass of the neutron star (NS) is susceptible to $G_{v}$ . When there is no repulsive force, the NS maximum mass is only about $1.5 M_{⊙}$ , but it becomes larger than $2.0 M_{⊙}$ when the vector coupling constant is about half of the {attractive} scalar coupling constant. Surprisingly, the presence of the quark matter does not affect the canonical mass of NS ( $1.4 M_{⊙}$ ), so observing the canonical mass of NSs can provide unique constraints to the EoS of hadronic matter at high densities.
Comments:
20 pages, 5 figures, 1 table
Subjects:
Nuclear Theory (nucl-th); High Energy Astrophysical Phenomena (astro-ph.HE); High Energy Physics — Phenomenology (hep-ph)
arXiv:
2307.09038 [pdf]
J.Korean Phys.Soc.(2024)·6 citations
05
[Submitted on 18 Jul 2023]
Drag force near the QCD critical point
Yukinao Akamatsu🇯🇵 · Masayuki Asakawa🇯🇵
We discuss how heavy quark dynamics is affected by the critical fluctuations near the QCD critical point at finite temperature and density. We find that the heavy quark momentum diffusion constant scales as $κ \propto ξ^{z - 3 - η}$ . In the model H scenario, which is widely accepted for the critical dynamics, the exponents are known as $z ≃ 3, η \sim 0.04$ and the critical singularity of $κ$ is not significant if any. In the model B scenario, $z ≃ 4$ and $κ \propto ξ$ is singular near the critical point.
Comments:
4 pages, accepted in Phys. Rev. C
Subjects:
Nuclear Theory (nucl-th); Quantum Gases (cond-mat.quant-gas); High Energy Physics — Phenomenology (hep-ph); Nuclear Experiment (nucl-ex)
arXiv:
2307.09049 [pdf]
PRC(2024)·1 citation
06
[Submitted on 18 Jul 2023]
Impact of nuclear structure on longitudinal flow decorrelations in high-energy isobar collisions
Maowu Nie🇨🇳 · Chunjian Zhang🇺🇸 · Zhenyu Chen🇨🇳 · Li Yi🇨🇳 · Jiangyong Jia🇺🇸
Fluctuations of harmonic flow along pseudorapidity, known as flow decorrelations, are an important probe of the initial state geometry of the quark-gluon plasma. The flow decorrelations are shown to be sensitive to the collective structure of the colliding nuclei, as revealed clearly by comparing collisions of isobars, $^{96}$ Ru+ $^{96}$ Ru and $^{96}$ Zr+ $^{96}$ Zr, which have different nuclear structures. The flow decorrelations in central collisions are mostly sensitive to nuclear deformations, while those in the mid-central collisions are primarily sensitive to differences in skin thickness between $^{96}$ Ru and $^{96}$ Zr. Longitudinal flow decorrelations in heavy-ion collisions are a new tool to probe the structure of colliding nuclei.
Comments:
It's almost the same as 2208.05416, i will simply replace the old one
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2307.09415 [pdf]
1 citation
07
[Submitted on 18 Jul 2023]
Influence of the tetraneutron on the EoS under core-collapse supernovae and heavy-ion collisions conditions
Helena Pais · Conrado Albertus · M. Ángeles Pérez-García · Constança Providência
Recently, a resonant state of four neutrons (tetraneutron) with an energy of $E_{4 n} = 2.37 \pm 0.38 (stat) \pm 0.44 (sys)$ MeV and a width of $Γ = 1.75 \pm 0.22 (stat) \pm 0.30 (sys)$ MeV was reported. In this work, we analyse the effect of including such an exotic state on the yields of other light clusters, that not only form in astrophysical sites, such as core-collapse supernovae and neutron star mergers, but also in heavy-ion collisions. To this aim, we use a relativistic mean-field formalism, where we consider in-medium effects in a two-fold way, via the couplings of the clusters to the mesons, and via a binding energy shift, to compute the low-density equation of state for nuclear matter at finite temperature and fixed proton fraction. We consider five light clusters, deuterons, tritons, heliums, $α$ -particles, and $^{6}$ He, immersed in a gas of protons and neutrons, and we calculate their abundances and chemical equilibrium constants with and without the tetraneutron. We also analyse how the associated energy of the tetraneutron would influence such results. We find that the low-temperature, neutron-rich systems, are the ones most affected by the presence of the tetraneutron, making neutron stars excellent environments for their formation. Moreover, its presence in strongly asymmetric matter may increase considerably the proton and the $α$ -particle fractions. This may have an influence on the dissolution of the accretion disk of the merger of two neutron stars.
Comments:
10 pages, 6 figures
Subjects:
Nuclear Theory (nucl-th); High Energy Astrophysical Phenomena (astro-ph.HE)
arXiv:
2307.09418 [pdf]
Astron.Astrophys.(2023)·6 citations
08
[Submitted on 18 Jul 2023]
Study of $β^{-}$ decays for sd model space with Shell model
Surender Siwach
This paper investigates the beta decay of nuclei within the sd model space, encompassing the $0 d_{3/2}$ , $0 d_{5/2}$ , and $1 s_{1/2}$ shells. We comprehensively analyze their decay characteristics, including the half-life, $l o g f t$ value, Q value, branching ratio, B(GT) value, M(GT), and R(GT) value. These results are compared with experimental data from Z = 8-19 nuclei, employing the nuclear shell model framework. The calculations are performed using the USDB\cite{usdb} interaction, which is well-suited for nuclei with active valence nucleons in the $0 d_{3/2}$ , $0 d_{5/2}$ , and $1 s_{1/2}$ shells. The study offers valuable insights into the beta decay properties of these nuclei and contributes to our understanding of the nuclear shell structure.}
Comments:
23 pages, 2 figures
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2307.09445 [pdf]
0 citations
09
[Submitted on 17 Jul 2023] (cross-list from hep-ph)
Equation of State of Cold Quark Matter to $O (α_{s}^{3} ln α_{s})$
Tyler Gorda🇩🇪 · Risto Paatelainen🇫🇮 · Saga Säppi🇩🇪 · Kaapo Seppänen🇫🇮
Accurately understanding the equation of state (EOS) of high-density, zero-temperature quark matter plays an essential role in constraining the behavior of dense strongly interacting matter inside the cores of neutron stars. In this Letter, we study the weak-coupling expansion of the EOS of cold quark matter and derive the complete, gauge-invariant contributions from the long-wavelength, dynamically screened gluonic sector at next-to-next-to-next-to-leading order (N3LO) in the strong coupling constant $α_{s}$ . This elevates the EOS result to the $O (α_{s}^{3} ln α_{s})$ level, leaving only one unknown constant from the unscreened sector at N3LO, and places it on par with its high-temperature counterpart from 2003.
Comments:
Corresponds to the published version. 7 pages (main text), 6 pages (supplemental material), 2 figures, 2 tables
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Astrophysical Phenomena (astro-ph.HE); Nuclear Theory (nucl-th)
arXiv:
2307.08734 [pdf]
PRL(2023)·82 citations
10
[Submitted on 17 Jul 2023] (cross-list from hep-lat)
Computing Jet Transport Coefficients On The Lattice
Amit Kumar🇩🇪 · Abhijit Majumder🇨🇦 · Ismail Soudi🇺🇸 · Johannes H. Weber🇺🇸
The leading jet transport coefficients $q^$ or $e^_{2}$ encode transverse or longitudinal momentum broadening of a hard parton traversing a hot medium. Understanding their temperature dependence is key to appreciating the observed suppression of high-transverse momentum probes at RHIC or LHC collision energies. We present a first continuum extrapolated result of $q^$ computed on pure SU(3) lattices with non-trivial temperature dependence different from the weak-coupling expectation. We discuss our formalism and its challenges and status in view of obtaining $e^_{2}$ or of unquenching the calculation. We consider a hard quark subject to a single scattering on the plasma. The transport coefficients are factorized in terms of matrix elements given as integrals of non-local gauge-covariant gluon field-strength field-strength correlators. After the analytic continuation to the deep-Euclidean region, the hard scale permits to recast these as a series of local, gauge-invariant operators. The renormalized leading-twist term in this expansion is closely related to static quantities, and is computed on pure SU(3) lattices ( $N_{τ} = 4, 6, 8,$ and $10$ ) for a wide range of temperatures, ranging from 200MeV < T < 1GeV. Our estimate for the unquenched result in $2 + 1$ -flavor QCD has very similar features.
Comments:
6 pages, 1 figure, HardProbes2023, 26-31 March 2023, Aschaffenburg, Germany
Subjects:
High Energy Physics — Lattice (hep-lat); High Energy Physics — Phenomenology (hep-ph); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2307.08834 [pdf]
PoS(2024)·1 citation
11
[Submitted on 17 Jul 2023] (cross-list from hep-ph)
A view of Coherent Elastic Neutrino-Nucleus Scattering
M. Cadeddu🇮🇹 · F. Dordei🇮🇹 · C. Giunti🇮🇹
We review the physics of coherent elastic neutrino-nucleus scattering and the results and perspectives for the measurements of the radius of the neutron distribution of the nucleus, of the weak mixing angle, and of new neutrino interactions due to physics beyond the Standard Model.
Comments:
Invited Perspective on CEvNS for EPL, 7 pages and 6 figures (updated with journal reference)
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2307.08842 [pdf]
EPL(2023)·34 citations
12
[Submitted on 17 Jul 2023] (cross-list from hep-ph)
Triple Charmonium Production in pQCD
B. Blok🇮🇱 · J. Mehl (Technion)🇮🇱
We study the role of $1 \to 2$ and $1 \to 3$ processes in triple charmonium production. We see that the ratio of effective cross sections of TPS and DPS only moderately depends on charmonium transverse momenta, but the total DPS and TPS cross sections each separately may have rather strong dependence on charmonia transverse momenta in the central kinematics that can be studied experimentally.
Comments:
15 pages, 7 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2307.08883 [pdf]
EPJC(2024)·1 citation
13
[Submitted on 17 Jul 2023] (cross-list from hep-ph)
Universality of sound modes in kinetic theory
Xiaojian Du🇪🇸 · Stephan Ochsenfeld🇩🇪 · Sören Schlichting🇩🇪
We present a simple approach to extract hydrodynamic sound modes and non-hydrodynamic modes in kinetic theories from response functions of the energy-momentum tensor. By comparing the response functions in four types of kinetic theories, namely the Relaxation-Time Approximation, scalar $ϕ^{4}$ theory, SU(3) Yang-Mills theory and QCD kinetic theory, we find a remarkable degree of universality for the sound mode, even beyond the hydrodynamic regime.
Comments:
6 pages, 4 figures; Proceeding on 11th International Conference on Hard and Electromagnetic Probes of High Energy Nuclear Collisions (Hard Probe 2023), 26-31 March 2023, Aschaffenburg, Germany
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2307.08886 [pdf]
PoS(2024)·1 citation
14
[Submitted on 18 Jul 2023] (cross-list from hep-ph)
Theoretical study on $Λ_{c}^{+} \to Λ K^{+} K ˉ^{0}$ decay and $Ξ^{*} (1690)$ resonance
Si-Wei Liu🇨🇳 · Qing-Hua Shen🇨🇳 · Ju-Jun Xie🇨🇳
We present a theoretical study of $Ξ^{*} (1690)$ resonance in the $Λ_{c}^{+} \to Λ K^{+} K ˉ^{0}$ decay, where the weak interaction part proceeds through the Cabibbo-favored process $c \to s + u d ˉ$ . Next, the intermediate two mesons and one baryon state can be constructed with a pair of $q q ˉ$ with the vacuum quantum numbers. Finally, the $Ξ^{*} (1690)$ is mainly produced from the final state interactions of $K ˉ Λ$ in coupled channels, and it is shown in the $K ˉ Λ$ invariant mass distribution. Besides, the scalar meson $a_{0} (980)$ and nucleon excited state $N^{*} (1535)$ are also taken into account in the decaying channels $K^{+} K ˉ^{0}$ and $K^{+} Λ$ , respectively. Within model parameters, the $K^{+} K ˉ^{0}$ , $K ˉ^{0} Λ$ and $K^{+} Λ$ invariant mass distributions are calculated, and it is found that our theoretical results can reproduce well the experimental measurements, especially for the clear peak around $1690$ MeV in the $K ˉ Λ$ spectrum. The proposed weak decay process $Λ_{c}^{+} \to Λ K^{+} K ˉ^{0}$ and the interaction mechanism can provide valuable information on the nature of the $Ξ^{*} (1690)$ resonance.
Comments:
9 pages, 5 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2307.09106 [pdf]
PRD(2023)·12 citations
15
[Submitted on 18 Jul 2023] (cross-list from hep-ph)
Radiative energy loss of heavy quark through soft gluon emission in QGP
Taesoo Song🇩🇪 · Ilia Grishmanovskii🇩🇪 · Olga Soloveva🇩🇪 · Elena Bratkovskaya🇩🇪
The Low's theorem is applied to the soft gluon emission from heavy quark scattering in quark-gluon plasma (QGP). The QGP is described by the dynamical quasi-particle model (DQPM) which reproduces the EoS from lQCD at finite temperature and chemical potential. We show that if the emitted gluon is soft and of long wavelength, the scattering amplitude can be factorized into the scattering part and the emission part and the Slavnov-Taylor identities are satisfied in the leading order. Imposing a proper upper limit on the emitted gluon energy, we obtain the scattering cross sections of charm quark as well as the transport coefficients (momentum drag and diffusion) in the QGP with and without gluon emission.
Comments:
6 pages, 3 figures, proceeding for the Hard Probes 2023
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2307.09124 [pdf]
PoS(2024)·0 citations
16
[Submitted on 18 Jul 2023] (cross-list from hep-th)
Quantum binding energies in the Skyrme model
Sven Bjarke Gudnason🇨🇳 · Chris Halcrow🇸🇪
A major problem in the Skyrme model is that the binding energy of skyrmions, which model nuclei, is too high by an order of magnitude. We show that the most popular solution to this problem, to construct models with zero classical binding energy, still produces large binding energies when spin energy is included. We argue that it is thus necessary to include quantum effects. We calculate the binding energy of skyrmions including the most simple quantum correction, that of vibrational modes in a harmonic approximation. We show that this can give physically reasonable results for nucleon numbers N=1-8 thanks to a remarkable cancellation between the strongly binding classical energy and the strongly unbinding zero-point energy from vibrational modes.
Comments:
5 pages, 3 figures
Subjects:
High Energy Physics — Theory (hep-th); Nuclear Theory (nucl-th)
arXiv:
2307.09272 [pdf]
PLB(2024)·12 citations
17
[Submitted on 13 Jul 2023] (cross-list from hep-ph)
Hard parton dispersion in the quark-gluon plasma, non-perturbatively
Jacopo Ghiglieri🇫🇷 · Guy D. Moore🇩🇪 · Philipp Schicho🇩🇪 · Niels Schlusser🇨🇭 · Eamonn Weitz🇫🇷
The in-medium dispersion of hard partons, encoded in their so-called asymptotic mass, receives large non-perturbative contributions from classical gluons, i.e. soft gluons with large occupation numbers. Here, we discuss how the analytical properties of thermal amplitudes allow for a non-perturbative determination of the infrared classical contribution through lattice determinations in the dimensionally-reduced effective theory of hot QCD, EQCD. We show how these lattice determinations need to be complemented by perturbative two-loop matching calculations between EQCD and QCD, so that the unphysical (classical) ultraviolet behavior of EQCD is replaced by its proper quantum QCD counterpart. We show how lattice and perturbative EQCD are in good agreement in the UV and present an outlook on the two-loop quantum QCD contribution.
Comments:
6 pages, to appear in the proceedings of Hard Probes 2023
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Lattice (hep-lat); Nuclear Theory (nucl-th)
arXiv:
2307.09297 [pdf]
PoS(2024)·3 citations

Affiliations

first authorsco-authorsvia INSPIRE