Nuclear Theory·nucl-th

Tuesday·March 24, 2026

14 papers—10 primary·4 cross-listed

01
Universality of the Majorana Double Charge Exchange
Caterina Garofalo🇮🇹 · Horst Lenske🇩🇪 · Francesco Cappuzzello🇮🇹 · Manuela Cavallaro🇮🇹
The Majorana Double Charge Exchange nuclear reaction mechanism represents a powerful and novel scenario to probe the dynamics of the neutrinoless double beta decay. Recent studies presented in this manuscript have highlighted a key feature of this mechanism, namely its independence with respect to the nuclei involved in the reaction.
nucl-thNuovo Cim.C(2026)·0 citations
02
Uncertainty quantification of holographic transport and energy loss for the hot and baryon-dense QGP
Musa R. Khan🇺🇸 · Ayrton Nascimento🇧🇷 · Yumu Yang🇺🇸 · Joaquin Grefa🇺🇸 · Mauricio Hippert🇧🇷 · Jorge Noronha🇺🇸 · Claudia Ratti🇺🇸 · Romulo Rougemont🇧🇷
We investigate several transport coefficients across the phase diagram of a holographic Einstein-Maxwell-Dilaton (EMD) model of hot and dense QCD with $N_{f} = 2 + 1$ flavors. Our results are obtained from an open-source implementation of this model in C++, publicly available as a module within the MUSES Framework. This code includes a new numerical method to extract thermodynamic quantities from near-boundary asymptotics in holographic models, introduced here for the first time, which greatly improves numerical stability and performance in comparison to earlier implementations. Thanks to this improved technique, we are able to compute results for many realizations of our holographic model, sampled from a Bayesian posterior distribution constrained by lattice QCD results at zero chemical potential. This allows us to propagate lattice QCD error bars to predictions of transport coefficients in a wide window of temperature and baryon chemical potential, covering the crossover region, the neighborhood of the predicted critical point, and the line of first-order phase transition. The physical observables include baryon and thermal conductivities, baryon diffusion, shear and bulk viscosities, the jet-quenching parameter, the heavy-quark drag force, and Langevin diffusion coefficients. At vanishing baryon density, we compare our results to estimates extracted by the JETSCAPE Collaboration from heavy-ion data, with which we find good agreement.
nucl-thhep-phhep-th4 citations
03
Production correlation of light (hyper-)nuclei in Au-Au collisions from the RHIC Beam Energy Scan
Jiang-He Qiao🇨🇳 · Jian-Yu Liu🇨🇳 · Yan-Ting Feng🇨🇳 · Feng-Lan Shao🇨🇳 · Rui-Qin Wang🇨🇳
Based on nucleons ( $p$ , $n$ ) and hyperons ( $Λ$ , $Ω^{-}$ ) formed at kinetic freeze-out from a quark combination model, we systematically study the production of light nuclei and hyper-nuclei in the hadronic coalescence picture. We present the analytical formula of the nucleus momentum distribution of two-body coalescence and that of three-body coalescence. We explain the experimental data of the transverse momentum spectra of deuteron ( $d$ ), triton ( $t$ ), helium-3 ( $^{3}$ He) and hypertriton ( $_{Λ}^{3}$ H) measured in Au-Au collisions from the RHIC Beam Energy Scan I and II, and also provide the corresponding predictions of different $Ω -$ hypernuclei $H (p Ω^{-})$ , $H (n Ω^{-})$ and $H (p n Ω^{-})$ . We further study the production correlations of different species of light (hyper-)nuclei and discuss their interesting behaviors as a function of collision energy.
nucl-thhep-exhep-ph0 citations
04
A Unified Theoretical Framework for HFB Resonant States: Integration of the Complex-Scaled Jost Function and Autonne-Takagi Normalization
Kazuhito Mizuyama
We develop a theoretical framework to describe quasiparticle resonance states within the Hartree-Fock-Bogoliubov (HFB) theory by integrating the complex-scaled Jost function method with the Autonne-Takagi factorization. The HFB completeness relation is derived from the analytical properties of the Green's function using contour integration in the complex energy plane, where the complex scaling method (CSM) is shown to be essential for explicitly separating resonance pole contributions from the continuum background. To uniquely define and normalize the resonant wave functions (Gamow states), the Autonne-Takagi factorization is applied to the rank-1 residue matrix of the flux-adjusted S-matrix at the pole energy. This scheme determines the absolute scale and phase of the eigenfunctions without relying on artificial adjustments or phenomenological basis sets. Numerical analysis confirms that physical observables and the defined wave functions remain invariant under the rotation of the complex scaling angle $θ$ . Furthermore, the T-matrix residues calculated via the Mittag-Leffler expansion are shown to be in exact numerical agreement with those obtained from the microscopic integrals of the Takagi-normalized Gamow states. Our analysis of the scattering profiles reveals that hole-type quasiparticle resonances can be understood as a manifestation of the Fano process originating from the interference between the discrete poles and the background continuum. The proposed normalization scheme provides a foundation for evaluating the collectivity of various excitation modes in open quantum many-body systems.
nucl-thPRC(2026)·0 citations
05
Bayesian extraction of TMC-free collectivity in p+p and p+Pb collisions at the LHC
Shuang Guo🇨🇳 · Jia-Lin Pei🇨🇳 · Guo-Liang Ma🇨🇳 · Adam Bzdak🇵🇱
A central challenge in understanding the origin of collective flow-like signatures in small collision systems calls for a reliable method to disentangle genuine collective flow from substantial background correlations, especially those arising from transverse momentum conservation (TMC). A Bayesian inference framework is developed to integrate TMC calculations with the LHC-ATLAS data on long-range multiparticle azimuthal correlation observables, thereby extracting genuine collective flow in small systems. Our analysis indicates that while the genuine elliptic and triangular flow ( $v_{2}$ and $v_{3}$ ) are similar, the $p$ + $p$ and $p$ +Pb systems exhibit distinct TMC backgrounds, TMC-flow interplay, and $v_{2}$ -- $v_{3}$ correlations. We demonstrate that the genuine $v_{2}$ and $v_{3}$ are well described by the measured four-particle $v_{2} {4}$ and two-particle $v_{3} {2}$ in $p$ +Pb collisions, whereas these measurements systematically underestimate the genuine flow in $p$ + $p$ collisions, due to competing contributions from TMC effects. This establishes a robust and data-driven approach, providing renewed theoretical insight into collective behavior free from TMC contamination in small collision systems.
nucl-thhep-phnucl-ex0 citations
06
Reaction Studies of Lepton Number Violation
Horst Lenske🇩🇪
Nuclear isotensor spectroscopy as accessible in nuclear double charge exchange (DCE) reactions is indispensable for quantitative studies of lepton number violation as in double beta decay (DBD). For such studies heavy ion double single charge exchange (DSCE) and direct Majorana double charge exchange (MDCE) reactions are discussed. Isotensor two-body transition densities are investigated for the first time. Pion-potentials, mirroring neutrino potentials, and isotensor short range correlations are explored. Lepton DCE (LDCE) reactions on nuclei at accelerators are introduced as a promising new approach to investigate lepton number violation.
nucl-thhep-phProceedings of the Mayorana Workshop, Mod…·0 citations
07
Systematic Cranked Shell Model Calculations for $^{87, 89, 91}$ Br
Nabeel Salim · Mehak Narula · P. Arumugam
A systematic investigation of the odd-mass neutron-rich bromine isotopes $^{87 - 91}$ Br has been carried out within the configuration-constrained cranked shell model (CSM) framework. The calculated kinematic moments of inertia and angular-momentum alignments reproduce the experimental trends with excellent agreement for the proposed quasiparticle configurations, thereby supporting the assigned band structures. The total Routhian surface calculations reveal pronounced $γ$ -softness in $^{87}$ Br, shape coexistence in $^{89 - 93}$ Br, and a gradual prolate-to-oblate transition approaching $N = 56$ . These results demonstrate that the CSM provides a reliable description of rotational behavior and shape evolution in this mass region, achieving a better level of accuracy, while offering a transparent interpretation of quasiparticle configurations and shape-driving effects.
nucl-th0 citations
08
Lepton Double Charge Exchange Reactions as Probes for Lepton Number Violation
H. Lenske · F. Cappuzzello · A. Spatafora
Lepton number violating (LNV) $A (e^{-}, e^{+}) X$ double charge exchange (LDCE) reactions on nuclei at accelerator facilities with multi-GeV beams are proposed as a probe for physics beyond the Standard Model (BSM). A second order formalism is presented including LNV dynamics by the left-right symmetric model (LRSM). For practical studies a phenomenological model is used to estimate LDCE cross sections numerically. Sizable cross sections are predicted for multi-GeV beam energies. LDCE reactions proceed preferentially by the energy-momentum dependent left-right mixing terms. While Majorana mass terms are negligible for light neutrinos, they may become sizable for heavy neutral leptons at higher beam energies. In the ~10 GeV region inclusive total LDCE cross sections of about $100 \times ∣ Γ_{B S M} ∣^{2}$ ~fb in units of the BSM vertices are predicted, increasing strongly with energy and target mass. LDCE experiments seem to be feasible with existing equipment under full laboratory control and free of the constraints imposed on decay or capture experiments of nuclear and hadronic systems.
nucl-th0 citations
09
Octupole deformation properties in the actinides region using Fayans functionals
Gauthier Danneaux · Markus Kortelainen
In this first-of-its-kind survey conducted on heavy and deformed nuclei in the actinide region of the nuclear chart, we have charted nuclear ground state properties predicted by Fayans energy density functionals (EDFs), focusing in particularly on octupole deformability. Compared to earlier studies with Skyrme-based EDFs, we found similar region of octupole deformed nuclei. Moreover, Fayans EDFs were found to provide accurate predictions for various ground state properties, when compared to experimental data. Comparison to Skyrme-based EDF shows similar trends in various nuclear properties.
nucl-thPRC(2026)·0 citations
10
S-wave kaon condensation in neutron-star matter within a chiral model framework with dynamical meson masses
Yuhan Wang🇺🇸 · Rajesh Kumar🇺🇸 · Joaquin Grefa🇺🇸 · Konstantin Maslov🇺🇸 · Claudia Ratti🇺🇸 · Rodrigo Negreiros🇺🇸 · Veronica Dexheimer🇺🇸
We investigate s-wave kaon condensation in dense matter and neutron stars within the updated Chiral Mean Field model with an improved meson description (mCMF), which incorporates dynamically generated in-medium meson masses arising from explicit chiral symmetry breaking and vector-meson self-interactions. In contrast to conventional relativistic mean-field descriptions with constant meson masses, the mCMF framework introduces a self-consistent feedback between the meson sector and the dense-matter equations of motion. The kaon dispersion relation is derived from the nonlinear SU(3) Lagrangian, including the Weinberg-Tomozawa interaction and additional baryon-pseudoscalar couplings, and the onset of condensation is determined under conditions of charge neutrality and $β$ equilibrium. Our calculations include the full baryon octet together with electrons and muons at zero temperature. We analyze the impact of hyperons, muons, and kaon condensation on the equation of state, on neutron-star mass--radius relations, and neutron-star thermal evolution, and examine the sensitivity of the onset density and stellar properties to variations in the nucleon--kaon scattering length and to different model vector parameters and vector self-interactions. We find that $K^{-}$ condensation sets in between $n \sim (2 - 8) n_{0}$ (in units of nuclear saturation density) and leads to a moderate to strong softening (in one case, a slight stiffening of the equation of state), depending on the interplay of kaons and hyperons, while remaining compatible with current $2 M_{⊙}$ and small-radius neutron-star observational constraints and producing distinguishable behavior in the neutron-star cooling. This work provides an improved and thermodynamically consistent framework for studying exotic degrees of freedom in neutron-star matter.
nucl-thastro-ph.HE2 citations
11
Elastic proton-proton and pion-proton scattering in holographic QCD
A. Watanabe🇯🇵
The elastic proton-proton and pion-proton scattering processes are investigated in the framework of holographic QCD. Considering the Pomeron and Reggeon exchange in the Regge regime, the total and differential cross sections are calculated. In the model setup, the Pomeron and Reggeon exchange are described by the Reggeized spin-2 glueball and vector meson propagator, respectively. For the differential cross sections, contributions of the Coulomb interaction are also taken into account. Adjustable parameters involved in the model are determined with the experimental data, and it is presented that the resulting cross sections are consistent with the data in a wide kinematic region.
↳ hep-phhep-exnucl-exnucl-th0 citations
12
Critical dynamics of the superfluid phase transition in Model F
Chandrodoy Chattopadhyay · Robert Maguire · Josh Ott · Thomas Schaefer · Vladimir V. Skokov
We describe numerical simulations of the critical dynamics near the superfluid phase transition. The calculations are based on an implementation of a stochastic hydrodynamic theory known as model F in the classification of Hohenberg and Halperin. This theory is expected to describe dynamic scaling near the lambda transition in liquid $^{4}$ He, Bose-Einstein condensation in ultracold atomic gases, and the superfluid transition in the unitary Fermi gas. Our simulation is based on a Metropolis algorithm previously applied to the critical endpoint of the liquid-gas phase transition in ordinary fluids. In the model E truncation of model F we obtain the expected dynamical exponent $z ≃ 3/2$ . We observe the emergence of a propagating second sound mode at the phase transition. The second sound diffusivity $D_{s}$ is consistent with the scaling relation $D_{s} \sim ξ^{x_{κ}}$ , where $ξ$ is the correlation length and $x_{κ} = 1/2$ .
↳ cond-mat.quant-gashep-phnucl-thPRA(2026)·2 citations
13
Jet quenching and its substructure dependence due to color decoherence
Xiang-Pan Duan🇨🇳 · Lin Chen🇪🇸 · Guo-Liang Ma🇨🇳 · Carlos A. Salgado🇪🇸 · Bin Wu🇪🇸
Motivated by color coherence and decoherence effects in the QCD medium, we propose a theoretical framework that combines vacuum-like emissions and medium-induced radiation to study jet quenching and its dependence on jet cone sizes and substructure. In our approach, a jet produced at a hard scale $Q$ first undergoes vacuum-like evolution, as described by the well-established generating-function method in the double logarithmic approximation. These vacuum-like emissions generate subjets at an infrared momentum scale $Q_{0}$ . Each subjet then experiences medium-induced energy loss as described by the BDMPS-Z formalism. By modeling the QCD bulk medium using OSU (2+1)-dimensional viscous hydrodynamics and treating $Q_{0}$ together with the jet-quenching parameters at the initial proper time of the hydrodynamic evolution as free parameters, our approach provides a very good description of the inclusive jet modification factor $R_{AA}$ for large-radius jets and its dependence on jet substructure in 0-10% PbPb collisions at $s_{N N} = 5.02 TeV$ , as measured by the ATLAS experiment.
↳ hep-phhep-exnucl-exnucl-th1 citation
14
Exact center symmetry and first-order phase transition in QCD with three degenerate dynamical quarks
Gergely Endrodi🇩🇪 · Guy D. Moore🇩🇪 · Adam Pieczynski🇩🇪 · Alessandro Sciarra🇩🇪
We study QCD with three degenerate flavors of dynamical quarks using first-principles lattice simulations. For a specific choice of imaginary isospin chemical potential, this theory possesses an exact center symmetry, just like pure gauge theory. This exact symmetry is expected to be intact at low temperatures and spontaneously broken in the high-temperature regime. By analyzing the finite-size scaling of the Polyakov loop distribution, obtained with a dedicated multi-histogram approach, we demonstrate that there is a first-order deconfinement phase transition in between. Our results are obtained employing stout-smeared rooted staggered quarks at one lattice spacing. Using simulations at different quark masses we sketch the behavior of QCD in the mass-isospin chemical potential plane, shedding new light on this corner of the fundamental phase diagram of the strong interactions and the relationship between chiral symmetry breaking and deconfinement.
↳ hep-lathep-phhep-thnucl-thPRD(2026)·2 citations

Affiliations

first authorsco-authorsvia INSPIRE