Nuclear Theory·nucl-th

Wednesday·July 22, 2026

14 papers—7 primary·7 cross-listed

01
The Nature of the Chemonuclear Reaction
Hidetsugu Ikegami · Masako Ikegami
In the chemonuclear reaction, the bulk of itinerant s-electrons revealing thermodynamical liquid activity in metallic systems undergo contact interaction with atomic nuclei and nucleons, thereby inducing contagiously thermodynamical liquid activity among the bulk of nuclei towards the chemical potential minimum, hence the united spontaneous, irreversible atomic and nuclear reactions. The chemonuclear reaction is enhanced with astronomical figures beyond the enhancement of few particle processes (e.g., in the electron-screened pycnonuclear fusion). In the systems of metallike hydride/deuteride and electron donor mixtures, self-sustained H-H and D-D chemonuclear fusion reactions take place. Unforeseen phenomena are observed, e.g., radiationless fusion and gamma-ray missing positron annihilation. In addition, the coherent D2-D2 and D3-D3 fusion reactions take place with enhancement factors over 20 to 30 and 30 to 46 figures of magnitude respectively. Through electron density correction on the chemical potential of reactants, the enhancement of chemonuclear fusion approaches to that of enhanced pycnonuclear fusion in astrophysical condensed plasma in the white dwarf progenitors of supernovae. In essence, chemonuclear fusion in condensed matters revealing thermo-dynamical liquid activity is identical to enhanced pycnonuclear fusion in astrophysical condensed plasma.
nucl-th0 citations
02
Influence of the Exit Channel in $^{235}$ U(n,f) and $^{239}$ Pu(n,f) Reactions in Time-Dependent Density Functional Theory
Ibrahim Abdurrahman · Matthew Kafker · Aurel Bulgac · Ionel Stetcu
This study investigates the consequences of the intrinsic deformation of the fissioning nuclear system near the outer saddle point on the shape evolution of the nucleus from saddle to scission and on the properties of the fission fragments. It is found that trajectories generally split into at least three classes, asymmetric, near-symmetric, and highly-asymmetric fission, that are roughly determined by the initial magnitude of the octupole moment, and each of which exhibits different scission dynamics and fragment properties. Near-symmetric modes result in a highly elongated neck at scission, leading to the neck rupture occurring when the proto-fragments are further apart than is the case for typical asymmetric fission, which in turn leads to a lower total kinetic energy and higher total excitation energy. The majority of this additional excitation energy goes into the heavy fission fragment, that develops a substantial quadrupole deformation. A similar trend is observed for the total kinetic energy of highly-asymmetric fission events, and the opposite trend for the excitation energy of the fission fragments as the majority of the additional excitation energy goes into the light fission fragment instead. The study also characterizes the neck rupture, including its effect on the emission of scission neutrons in near-symmetric fission.
nucl-th1 citation
03
Charge-symmetry-breaking effects on displacement energies and charge radius differences in mirror nuclei
Myeong-Hwan Mun · Kyoungsu Heo · Jubin Park · Myung-Ki Cheoun · H. Sagawa
We study the effect of charge symmetry breaking (CSB) energy density function (EDF) on the mirror displacement energies (MDEs) and charge radius differences of mirror nuclei within the self-consistent Hartree-Fock-Bogolyubov (HFB) model taking Skyrme EDFs, SLy4 and SkM* as the central part of nuclear potential. We introduce the volume and the derivative terms in CSB EDF and calibrate the strength adopting four reference mirror pairs $^{34}$ Ar-- $^{34}$ S, $^{36}$ Ca-- $^{36}$ S, $^{38}$ Ca-- $^{38}$ Ar, and $^{54}$ Ni-- $^{54}$ Fe, for which experimental data of both MDEs and mirror charge-radius differences are available. We introduce a sensitivity matrix which connects two CSB terms to residuals of MDEs and mirror charge-radius differences after subtracting the effect of Coulomb interaction. By using the sensitivity matrix, we found out that the derivative term is important to reproduce both observables in a good accuracy together with the volume term, especially for the residual of mirror charge radii. The optimized CSB EDF are further applied to predict the charge radius differences of mirror pairs, $^{40}$ Ti-- $^{40}$ Ar, $^{42}$ Ti-- $^{42}$ Ca, $^{46}$ Cr-- $^{46}$ Ti, and $^{50}$ Fe-- $^{50}$ Cr. We pointed out also that the CSB effects change neutron skins of mirror proton-rich nuclei at the $1 0^{- 2}$ fm level so that the CSB contributions must be included before charge-radius differences between mirror nuclei are used to extract neutron-skin or symmetry-energy parameters.
nucl-th0 citations
04
Nonlinear collective flow reveals the breakdown of quadrupole--hexadecapole scaling in heavy ion collisions
Hadi Mehrabpour🇨🇳 · Zahra Sheibani🇮🇷 · Li Yan🇨🇳 · Chunjian Zhang🇨🇳 · Abolfazl Mirjalili🇮🇷
Determining the role of intrinsic hexadecapole deformation ( $β_{4}$ ) in nuclear structure remains a long-standing challenge. Relativistic heavy-ion collisions provide a unique opportunity to address this problem by converting the initial nuclear geometry into the collective motion of the quark--gluon plasma (QGP). Using event-by-event viscous hydrodynamic simulations of ultra-central $^{238}$ U+ $^{238}$ U collisions at $s_{N N} = 193$ GeV, we investigate whether higher-order collective flow can isolate the contribution of $β_{4}$ and test the $β_{2} - β_{4}$ correlation. We demonstrate that information carried by the sign of $β_{4}$ survives the QGP evolution and is enhanced through nonlinear hydrodynamic response: the fourth-order flow harmonic acquires its topology dependence predominantly from the linear response, whereas the sensitivity of the sixth-order harmonic originates almost entirely from nonlinear mode coupling. As a consequence, the nonlinear response coefficient $ξ_{6, 222}$ cleanly separates the $(β_{2}, β_{4})$ intrinsic nuclear topologies. These results establish the sign of $β_{4}$ as an experimentally accessible signature of deviations from the quadrupole--hexadecapole correlation, demonstrating that higher-order collective flow provides a direct probe of nuclear multipole structure while revealing how nonlinear QGP dynamics encode subtle higher-order geometric information into final-state observables.
nucl-thhep-exhep-phnucl-ex0 citations
05
Mapping parametric error profiles onto nuclear structure configurations in deformed proton radioactivity
Jizheng Bo
Theoretical descriptions of proton radioactivity near the drip lines are often challenged by parametric uncertainties in nuclear potential models. To address this, a robust Bayesian uncertainty quantification (UQ) framework is established to calibrate the deformed Woods--Saxon potential coupled with the semi-classical WKB approximation for odd- $A$ proton emitters across the $Z = 50$ -- $82$ region. Constrained by experimental half-lives, the joint and marginal posteriors and covariance topologies are extracted for the potential geometry, multipole deformations, and spectroscopic factors. Using a signed relative sensitivity index, a dynamic, mass-dependent re-ordering of parameter hierarchies is unraveled. Crucially, propagating these parametric uncertainties yields posterior predictive medians and differentiated $σ$ bands that tightly encompass experimental half-lives across multiple orders of magnitude without systematic bias. Furthermore, near the $Z = 82$ shell closure, the structural softening of the nuclear potential manifests as a systematic expansion and volatility of the $σ$ bands in the deformation profiles. This correlation suggests that the macroscopic behavior of parametric error distributions can potentially be mapped onto potential energy configurations, underscoring that the Bayesian UQ methodology may serve as a sensitive probe to extract reliable nuclear structure information directly from deformed proton decay systematics.
nucl-th0 citations
06
Quarkyonic Stars with Strangeness
Jin-Biao Hu🇳🇱 · Jun-Ting Ye🇳🇱 · Si-Pei Wang🇳🇱 · Rui Wang🇳🇱 · Zhen Zhang🇳🇱 · Lie-Wen Chen🇳🇱
We propose an extension of the quarkyonic matter framework that includes $u$ , $d$ , and $s$ quarks and the full baryon octet. Within this extended framework, we impose beta-equilibrium between baryons and leptons, while determining the quark fractions from the constituent quark contents of baryons. The hadronic sector of octet baryons is described by a recently developed density, momentum and isospin dependent effective interaction based on the N3LO Skyrme pseudopotential, whereas quarks and leptons are treated as free particles. We find that the quarkyonic mechanism can obviously reduce the critical density for hyperon appearance in neutron stars due to the fact that the nucleons are displaced to higher momentum states in quarkyonic matter and their chemical potentials rise accordingly. Furthermore, the quarkyonic mechanism can significantly stiffen the equation of state of hyperon star matter and thereby enhance the hyperon star maximum mass, thus helping to mitigate the hyperon puzzle.
nucl-thastro-ph.HEhep-phnucl-ex0 citations
07
Temperature fluctuations in a realistic Polyakov-loop extended Nambu--Jona-Lasinio Model along the freeze-out line
He Liu · Peng Wu · Hong-Ming Liu · Peng-Cheng Chu
We extend and reparameterize the Polyakov--Nambu--Jona-Lasinio (PNJL) model to reproduce lattice simulation data at zero baryon chemical potential and to position its critical endpoint (CEP) within the BES-II experimental energy range. Using this realistic PNJL model, we investigate the behavior of the second-order temperature cumulant $C_{2}$ along the freeze-out line, aiming to understand the non-monotonic energy dependence of the two-particle transverse momentum correlation $C_{p_{T}}$ observed by the STAR Collaboration. Our results show a distinct dip structure in $C_{2}$ near the CEP and the first-order phase boundary on the phase diagram. Along the experimentally extracted freeze-out line, the dip minimum occurs around 7.7 GeV, and its trend is consistent with that observed by STAR, suggesting that the non-monotonic dependence of $C_{p_{T}}$ may be related to the CEP. Our results also indicate that cumulant ratios such as $C_{3} / C_{2}^{2}$ or $C_{4} / C_{2}^{3}$ eliminate the influence of initial volume fluctuations and may better reveal the underlying critical fluctuations. Further verification could be pursued through hydrodynamic or transport simulations that incorporate critical dynamics. These results and predictions might provide an a priori theoretical basis for future experimental measurements of higher-order event-mean transverse momentum fluctuations.
nucl-thnucl-ex0 citations
08
Zero of the proton electric form factor in the finite value of the spacelike momentum transfer squared
Erik Bartoš🇸🇰 · Stanislav Dubnička🇸🇰 · Noel Vincze🇸🇰 · Andrej Liptaj🇸🇰 · Anna Zuzana Dubničková🇸🇰
The behavior of the polarization data on $μ_{p} (G_{E}^{p} (t) / G_{M}^{p} (t))$ ratio, at the present day available up to $t = - 8.5$ GeV $^{2}$ , obtained in the Jefferson Lab experiments carried out by the Akhiezer-Rekalo polarization method, has a decreasing tendency, indicating possible existence of a zero of the proton electric form factor $G_{E}^{p} (t)$ in the finite spacelike momentum transfer squared value. However, recently appeared two papers, investigating these data, one of them including also other existing data on the nucleon electromagnetic structure in the spacelike and timelike regions, in which an existence of such zero is disproved. Nevertheless, reinvestigations we provide in this paper give clear arguments for the possible existence of such a zero.
↳ hep-phnucl-th0 citations
09
A First Bound on the Moffat Energy and Thorium-229 Clock as a Probe of the Nonlocal Time-Energy Structure and a Proposed Experiment for the use of Nuclear Entanglement and Squeezed States to Test Nonlocal Quantum Field Theory
E. J. Thompson🇨🇦 · Arvin Kouroshnia🇨🇦 · J. W. Moffat🇨🇦 · C. Chyrak🇨🇦 · G. Gervais🇨🇦 · H. A. Carteret🇨🇦
In this paper we derive the nonlocal Time-Energy uncertainty principle and then apply the published $^{229}$ Th nuclear clock data as a first probe of the nonlocality scale $E_M$. By using the direct clock-energy channel, we find conservative lower bounds on $E_M$ at the tens of MeV scale, with optimistic present-data estimates reaching the hundred MeV scale. Including the known nuclear sensitivity enhancement of the $^{229}$ Th transition gives us stronger model dependent bounds in the GeV range, while nuclear-scale reference-energy scenarios can reach the TeV range. The conclusion we draw from this is that nuclear clocks already provide an experimental route from nonlocal time--energy uncertainty to measurable laboratory bounds on non-Planckian nonlocality. We explore the idea of using a squeezed-state experiment with the $^{229} Th$ nuclear clock to test the time--energy structure of nonlocal quantum field theory. The idea is reasonably obtainable within the near future of nuclear clock experiments. One would prepare an ensemble of thorium nuclei in a coherent superposition of the nuclear ground state and the low-lying isomeric clock state, entangle the participating nuclei through a collective interaction, and generate a family of spin-squeezed states with a tunable squeezing parameter $r$ . Then a phase-controlled analysis pulse will rotate the selected collective nuclear quadrature into a measurable ground-isomer population difference. Near a strongly polarized collective state the normalized operators $J_{y} / S$ and $J_{z} / S$ obey the same approximate canonical algebra as the phase and amplitude quadratures of a squeezed optical mode. We use this experiment to either probe or bound the nonlocal energy scale $E_{M}$ .
↳ quant-phhep-exhep-phhep-th+11 citation
10
Soft Gluon Wave Function and Evolution Operator in the CGC at Next-to-Leading Order
Ramkumar Radhakrishnan🇺🇸
We construct the soft gluon light cone wave function of a fast moving hadron and the associated unitary evolution operator $Ω$ up to $O (g^{2})$ in pure Yang Mills theory $(N_{f} = 0)$ , within the Color Glass Condensate (CGC) framework. Working in light cone gauge, we perform a Born Oppenheimer separation between fast valence and soft modes and implement the eikonal approximation, which allows $Ω$ to be written as a fully normal ordered series in soft gluon creation and annihilation operators. The expansion coefficients are functionals of the non-commuting valence color charge density operators $ρ$ . We fix the coefficients by using the unitarity and explicit diagrammatic calculations within light-cone perturbation theory (LCPT). As an application, we diagonalize the pure Yang Mills soft Hamiltonian through orders $g$ and $g^{2}$ and show that the off diagonal mixing elements between Fock sectors cancel leading to the coherent background field energy proportional to $ρ^{2}$ .
↳ hep-phhep-thnucl-th0 citations
11
Viscoelastic and thermal response on nuclear pasta states at finite baryon density
Nicolás Grandi🇦🇷 · Scarlett Rebolledo🇺🇸 · Aldo Vera🇨🇱
We compute the viscoelastic and thermal response of non-homogeneous hadronic condensates at finite baryon density representing crystals of baryonic tubes and layers. We describe them using analytic solutions of the Skyrme model in $3 + 1$ dimensions as ground states for a perturbative approach. At low enough temperatures, the lowest-energy excitations are described by a free massless scalar field theory in $1 + 1$ dimensions. We apply the Green-Kubo formulas to such excitations to obtain the elasticity tensor and other response coefficients. The analytic results of our computations are compared with available results on the nuclear pasta phase.
↳ hep-thnucl-th0 citations
12
Ultra-peripheral Collisions
Jesus Guillermo Contreras🇨🇿 · Spencer Robert Klein🇺🇸
Photons in ultra-peripheral collisions of heavy ions (and protons) can be used for a variety of physics purposes - for studies of nuclear structure at low Bjorken $- x$ , as probes of beyond-standard-model physics at the highest possible photon energies, and to explore new regimes of quantum mechanics via interferometry between two photon sources that share no common origin. This review will present the origins of photons in ultra-peripheral collisions and discuss the important physics that is being done with these photons, with particular emphasis on those on the energy frontier for photon physics.
↳ hep-exhep-phnucl-exnucl-th0 citations
13
Transport phenomena and observables associated with viscous properties of an anisotropic hot QCD medium at finite baryon asymmetry
Shubhalaxmi Rath🇨🇱 · Nicolás A. Neill🇨🇱
We have studied the transport phenomena and observables associated with viscous properties of a baryon asymmetric hot QCD medium in the presence of a weak-momentum anisotropy arising due to the asymptotic expansion of the matter in the initial stages of ultrarelativistic heavy-ion collisions. This study facilitates the understanding of the sound attenuation in the medium through the Prandtl number, the nature of flow through the Reynolds number, fluid behavior through the specific shear viscosity, and conformal symmetry through the specific bulk viscosity for an anisotropic hot QCD medium at finite baryon asymmetry. We have determined the shear and bulk viscosities by solving the relativistic Boltzmann transport equation in the relaxation time approximation method. The interactions among partons are incorporated through their distribution functions within the quasiparticle model of hot QCD medium at finite temperature, anisotropy and baryon asymmetry. We have observed a decrease in the shear and bulk viscosities in the presence of expansion-induced anisotropy for baryonless scenario as well as for baryon asymmetric scenario. Conversely, these viscosities are larger in baryon asymmetric matter compared to their counterparts in baryonless matter. The impact of anisotropy on baryon asymmetric matter is observed to be as conspicuous as on baryonless matter. The above results are broadly attributed to the squeezing of the distribution function due to the momentum anisotropy generated by the asymptotic expansion of baryon asymmetric matter and the dispersion relations of partons in the presence of anisotropy. Additionally, the aforesaid observables are also significantly modulated by the expansion-induced anisotropy in the baryon asymmetric medium, indicating new predictions for the sound attenuation, flow characteristics, fluid behavior and conformal symmetry of the said medium.
↳ hep-phhep-thnucl-th0 citations
14
Resolving the $T_{cc}^{+}$ with $π$ Exchange from Lattice QCD
Nelson Pitanga Lachini🇬🇧 · Raúl A. Briceño🇺🇸
We revisit the lattice QCD description of the doubly charmed tetraquark $T_{cc}^{+}$ using a finite-volume scattering formalism that incorporates one-pion exchange nonperturbatively, thereby making the nearest left-hand cut explicit while respecting unitarity and analyticity. We simultaneously determine the $D D^{⋆} π$ coupling and the isoscalar $D D^{⋆}$ scattering amplitude by reanalyzing the previously computed finite-volume $D D^{⋆}$ spectrum below the $D^{⋆} D^{⋆}$ threshold, on lattices with pion mass $m_{π} \approx 391 MeV$ . We find that the inclusion of pion exchange changes the $T_{cc}^{+}$ from a real-valued to a complex-valued pole in the second sheet of the $J^{P} = 1^{+}$ , $D D^{⋆}$ amplitude below threshold. We further predict that the $T_{cc}^{+}$ pole will move closer to the real-energy axis as the pion mass approaches its physical value.
↳ hep-lathep-phnucl-th1 citation

Affiliations

first authorsco-authorsvia INSPIRE