Nuclear Theory·nucl-th

Thursday·January 8, 2026

8 papers—4 primary·4 cross-listed

01
[Submitted on 7 Jan 2026]
$n p \leftrightarrow d γ$ reactions calculated up to $E_{γ} = 20$ MeV
Mamoon A. Sharaf · Weijie Du · Andrey M. Shirokov
We calculate the electromagnetic dipole transition cross sections for the $n p \to d γ$ and $d γ \to n p$ reactions over a broad range of energies. We use the LENPIC nucleon-nucleon interaction obtained from chiral effective field theory ( $χ$ EFT) up to next-to-next-to-next-to-next-to-leading order (N4LO) and effective electromagnetic dipole transition operators obtained from the same $χ$ EFT up to N2LO. Our results agree with existing experiments. We get results at energies for which experimental data and/or modern theoretical calculations have not been reported. In this study, we utilize a new approach, namely, our adaptation of the Efros [V. D. Efros, Phys. Rev. C 99, 034620 (2019)] method that is prospective for future many-body applications in calculations of bound and continuum state wave functions.
Comments:
12 pages, 6 figures, 2 tables. We welcome comments
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2601.03602 [pdf]
0 citations
02
[Submitted on 7 Jan 2026]
Gorkov algebraic diagrammatic construction for infinite nuclear matter
Francesco Marino · Carlo Barbieri · Gianluca Colò
We propose a novel many-body truncation for Gorkov self-consistent Green's function (SCGF) theory where pairing correlations are handled at first order, while dynamical correlations are described using the particle-number-conserving Dyson-SCGF scheme up to third order in the algebraic diagrammatic construction. The new method is enabled by the introduction of a scheme that allows to approximate the Gorkov propagator in terms of a particle-number-conserving optimized reference state. The approach provides state-of-the-art predictions of the equation of state and spectral properties of infinite nuclear matter at zero temperature and in the presence of pairing. We find satisfactory results using modern saturating Hamiltonians at next-to-next-to-leading order in chiral effective field theory.
Subjects:
Nuclear Theory (nucl-th); Quantum Gases (cond-mat.quant-gas); Strongly Correlated Electrons (cond-mat.str-el)
arXiv:
2601.03763 [pdf]
PRC(2026)·6 citations
03
[Submitted on 7 Jan 2026]
Improved microscopic nuclear level densities within the triaxial Hartree-Fock-Bogoliubov plus combinatorial method
S. Goriely🇧🇪 · W. Ryssens🇧🇪 · S. Hilaire🇫🇷 · A.J. Koning🇦🇹
New developments have been brought to our energy-, spin- and parity-dependent nuclear level densities based on the microscopic combinatorial method. Our new calculation is based on the BSkG3 mean-field model which relies on a three-dimensional coordinate-space representation of the nucleus, allowing for the spontaneous breaking of ground state rotational, axial and reflection symmetry. In particular, we now account for the impact of possible triaxial deformation of nuclear ground states on the level density. This has two effects on our calculations: the additional freedom of the single-particle levels affects the intrinsic level density while the absence of a rotational symmetry axis results in a larger collective correction. The present model reproduces the experimental s- and p-wave neutron resonance spacings with a degree of accuracy comparable to that of the best global models available. It is also shown that the model gives a reliable extrapolation at low energies where experimental data on the cumulative number of levels can be extracted. The predictions are also in good agreement with the experimental data extracted from the Oslo method. Total level densities for more than 8500 nuclei are made available in a table format for practical applications. For the nuclei for which experimental s-wave spacings and enough low-lying states exist, renormalization factors are provided to reproduce simultaneously both observables. The same combinatorial method is used to estimate the nuclear level densities at the fission saddle points of actinides and at the shape isomer deformation. Finally, the new nuclear level densities are applied to the calculation of radiative neutron capture cross sections and compared with those obtained with our previous combinatorial model.
Comments:
19 pages
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2601.03804 [pdf]
PRC(2026)·3 citations
04
[Submitted on 7 Jan 2026]
Thermal Evolution of Shape Coexistence in Mo and Ru Isotopes
Mamta Aggarwal · Pranali Parab · A. Jain · G. Saxena
The temperature-driven shape dynamics of isotopic chains of Mo and Ru elements and their impact on decay modes have been investigated in a statistical theoretical framework with macroscopic-microscopic apporach. These isotopes located at the key points in r-process path are known for the rapid structural changes, shape instabilities and shape coexistence that impact the nuclear processes, decay modes and lifetimes. At high temperatures that may exist in stars or in various nuclear reaction processes, these nuclei undergo a variety of shape and deformation changes due to thermal shell quenching effects influencing the decay energies (Q value), and eventually life-time have been studied in detail. Our findings provide insight into the observed shift in the deformation, shapes and coexisting states due to the diminishing nuclear shell effects in hot nuclei, revealing that the structural changes influence the decay processes and significantly in the astrophysically relevant Mo-Ru region especially around A = 100.
Comments:
15 pages, 5 figures
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2601.03838 [pdf]
NPA(2026)·1 citation
05
[Submitted on 7 Jan 2026] (cross-list from hep-ph)
Role of $Σ (1660)$ in the $K^{-} p \to π^{0} π^{0} Σ^{0}$ reaction
Xing-Yi Ji🇨🇳 · Si-Wei Liu🇨🇳 · Wen-Tao Lyu🇨🇳 · De-Min Li🇨🇳 · En Wang🇨🇳 · Ju-Jun Xie🇨🇳
The processes of $K^{-} p \to π^{0} π^{0} Σ^{0}$ and $K^{-} p \to π^{0} Λ (1405)$ are studied within the effective Lagrangian approach. In addition to the ``background" contribution from the $u$ -channel nucleon pole term, contribution from the $Σ (1660)$ resonance with spin-parity $J^{P} = 1/ 2^{+}$ is also considered. For the $K^{-} p \to π^{0} π^{0} Σ^{0}$ reaction, we perform a calculation for the total and differential cross sections by considering the contribution from the $Σ (1660)$ intermediate resonance decaying into $π^{0} Λ (1405)$ with $Λ (1405)$ decaying into $π^{0} Σ^{0}$ . With our model parameters, the available experimental data on both the $K^{-} p \to π^{0} π^{0} Σ^{0}$ and $K^{-} p \to π^{0} Λ (1405)$ reactions can be fairly well reproduced. It is shown that we really need the contribution from the $Σ (1660)$ resonance, and that these experimental measurements could be used to determine some properties of the $Σ (1660)$ resonance.
Comments:
7 pages, 6 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2601.03692 [pdf]
CPC(2026)·0 citations
06
[Submitted on 7 Jan 2026] (cross-list from quant-ph)
Scattering phase shift in quantum mechanics on quantum computers
Peng Guo🇺🇸 · Paul LeVan🇺🇸 · Frank X. Lee🇺🇸 · Yong Zhao🇺🇸
We investigate the feasibility of extracting infinite volume scattering phase shift on quantum computers in a simple one-dimensional quantum mechanical model, using the formalism established in Ref.~\cite{Guo:2023ecc} that relates the integrated correlation functions (ICF) for a trapped system to the infinite volume scattering phase shifts through a weighted integral. The system is first discretized in a finite box with periodic boundary conditions, and the formalism in real time is verified by employing a contact interaction potential with exact solutions. Quantum circuits are then designed and constructed to implement the formalism on current quantum computing architectures. To overcome the fast oscillatory behavior of the integrated correlation functions in real-time simulation, different methods of post-data analysis are proposed and discussed. Test results on IBM hardware show that good agreement can be achieved with two qubits, but complete failure ensues with three qubits due to two-qubit gate operation errors and thermal relaxation errors.
Comments:
Title changed to Scattering phase shift in quantum mechanics on quantum computers, and updated version match to accepted draft at PRD
Subjects:
Quantum Physics (quant-ph); High Energy Physics — Lattice (hep-lat); High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2601.04092 [pdf]
PRD(2026)·5 citations
07
[Submitted on 7 Jan 2026] (cross-list from hep-ph)
Complete NLO BFKL impact factors for quarkonium hadroproduction in NRQCD: the case of $^{1} S_{0}^{[1]}$ , $^{1} S_{0}^{[8]}$ , and $^{3} S_{1}^{[8]}$ states
Michael Fucilla🇵🇱 · Jean-Philippe Lansberg🇫🇷 · Maxim Nefedov🇮🇱 · Lech Szymanowski🇵🇱 · Samuel Wallon🇫🇷
We present the first complete next-to-leading-order calculation of the impact factors for hadroproduction of the $^{1} S_{0}^{[1]}$ , $^{1} S_{0}^{[8]}$ , and $^{3} S_{1}^{[8]}$ NRQCD states within the BFKL formalism. We complete the recent virtual-correction computation presented in JHEP 12 (2024) 129 by that of the real-emission contributions. We observe the cancellation of the soft divergences between these real- and virtual-emission contributions and we note that the surviving collinear singularities are compatible with factorisation up to one loop for a novel class of processes where BFKL resummation can be applied. Our work indeed represents the first complete NLO quarkonium impact factor in the BFKL framework and paves the way to first next-to-leading-logarithmic-precision studies for hadroproduction of forward-backward quarkonium associated production at hadron colliders.
Comments:
52 pages, 6 figures; version submitted to JHEP; broken references fixed
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); Nuclear Theory (nucl-th)
arXiv:
2601.04142 [pdf]
JHEP(2026)·0 citations
08
[Submitted on 7 Jan 2026] (cross-list from hep-lat)
Three-particle scattering amplitudes from lattice QCD
Stephen R. Sharpe🇺🇸
I review recent progress in calculating scattering amplitudes and resonance properties involving three particles using results from lattice QCD. The necessary input is the finite-volume spectrum, and the outputs -- via solutions of integral equations -- are scattering amplitudes that can be continued into the complex plane to search for resonance poles. I describe the outlook for future extensions and applications of this work.
Comments:
Plenary talk at Lattice 2025. 26 pages, 7 figures. v2: minor improvements in text, typos corrected
Subjects:
High Energy Physics — Lattice (hep-lat); High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Theory (hep-th); Nuclear Theory (nucl-th)
arXiv:
2601.04147 [pdf]
9 citations

Affiliations

first authorsco-authorsvia INSPIRE