Nuclear Theory·nucl-th

Wednesday·August 5, 2026

13 papers—7 primary·6 cross-listed

08
The Momentum Fraction, Helicity and Transversity Isovector Moments of Nucleons from \texorpdfstring{ $2 + 1$ }{2+1}-flavor Lattice QCD
Santanu Mondal🇮🇳 · Rajan Gupta🇺🇸 · Sungwoo Park🇰🇷 · Jun-sik Yoo🇰🇷 · Tanmoy Bhattacharya🇺🇸 · Boram Yoon🇺🇸 · Bálint Joó🇺🇸 · Frank Winter🇺🇸
Results for the isovector momentum fraction, $⟨ x ⟩_{u - d}$ , helicity moment, $⟨ x ⟩_{Δ u - Δ d}$ , and the transversity moment, $⟨ x ⟩_{δ u - δ d}$ , of the nucleon are presented using high-statistics data on thirteen NME ensembles of gauge configurations generated by the JLab/W\&M/LANL/MIT/Marseille collaborations using $2 + 1$ -flavors of dynamical Wilson-clover quarks. The much higher statistics facilitated better control over all systematics compared to our previous lattice calculation. The least controlled systematic---excited-state contamination---is quantified by studying the variation of the results as a function of three estimates of the mass gap of the first excited state, obtained from two- and three-point correlation functions. The final results are obtained using a simultaneous fit to extrapolate in the lattice spacing, $a$ , pion and kaon masses, $M_{π}$ and $M_{K}$ , and the finite volume parameter, $M_{π} L$ . The data show no significant finite-volume correction, and some dependence on the lattice spacing and the renormalization factors. The largest systematic uncertainty is due to possible remaining excited states contributions. Our final results, in the $MS$ scheme at 2~GeV, are $⟨ x ⟩_{u - d} = 0.154 (10) (9)$ , $⟨ x ⟩_{Δ u - Δ d} = 0.177 (10) (15)$ and $⟨ x ⟩_{δ u - δ d} = 0.197 (12) (18)$ , where the first error is the overall statistical uncertainty and the second represents the various systematic uncertainties added in quadrature. Results for the momentum fraction and helicity moment are consistent with phenomenological global fit values, while the transversity moment is a prediction.
↳ hep-latnucl-th0 citations
09
The Utility of Sparse Error Detection in Quantum Simulations
Henry Froland · Dorota M. Grabowska · Sebastian Grieninger · Jeremy Hartse · Anne L. Lashbrook · Zhiyao Li · Ziyuan Li · Sarah J. M. Powell · Martin J. Savage · Xiaojun Yao · Nikita A. Zemlevskiy
The recent success of error detecting codes points toward their potential application to fault-tolerant simulations of nature. In this work, we examine the utility of sparse error detection for simulating lattice gauge theories using quantum computers. In particular, we study the time evolution of the lattice Schwinger model embedded into the Iceberg code family, $[[N + 2, N, 2]]$ , as well as the Hypercube code family, $[[2^{N}, N, 2]]$ . The lattice of electrons and positrons in the axial gauge is embedded into a single code block or into multiple code blocks, and this work finds that large codeblocks are advantageous in the absence of connectivity constraints. Noisy classical simulations with realistic near-term error rates, infrequent syndrome measurements and physics-aware postselection are found to improve observable estimation. Under realistic noise rates for near-term quantum computers, this work finds that sparse error detection in quantum simulations has the potential to improve accuracy of observable estimation. Additional rounds of error detection are found to systematically drive errors in observables to the noise floor set by the code. These findings suggest that incorporating minimal implementations of fault tolerance in the near-term will enhance the performance of quantum simulations in nuclear physics and high-energy physics.
↳ quant-phhep-lathep-phnucl-th1 citation
10
Critical coupling with zero-mode corrections in discretized light-cone quantized $ϕ^{4}$ theory
Shreeram Jawadekar🇺🇸 · Mamoon A. Sharaf🇺🇸 · James P. Vary🇺🇸
We present an advancement for solving the Discretized Light-Cone Quantization (DLCQ) Hamiltonian for mass spectra in 2D $ϕ^{4}$ theory that incorporates perturbative zero-mode contributions. We demonstrate that this correction accelerates numerical convergence of the mass eigenstates with increasing resolution and yields a critical coupling of comparable accuracy with a substantial reduction in computational costs. Specifically, with more than one order of magnitude reduction in basis space dimensionality we achieve an extrapolated critical coupling of $23.10 \pm 0.25$ compared with $23.53 \pm 0.26$ in the larger basis but without zero-mode correction. We employ Gaussian Process Regression for extrapolation to the continuum limit. The approach we present here is prospective for studies of higher-dimensional gauge theories.
↳ hep-phhep-thnucl-th0 citations
11
Faddeev equations for the $J / ψ N N$ and $ϕ N N$ three-body systems in momentum space
Xu Zhang🇨🇳
We construct Faddeev equations for the $J / ψ N N$ and $ϕ N N$ three-body systems in momentum space. The two-body subsystem $t$ -matrix is obtained by solving the Lippmann-Schwinger equations. The $N N$ interactions are constructed using the Malfliet-Tjon potential. The $J / ψ N$ interaction potentials in the $^{4} S_{3/2}$ and $^{2} S_{1/2}$ channels are taken from HAL QCD. The $ϕ N$ interaction potential in the $^{4} S_{3/2}$ channel is also taken from HAL QCD. The $^{2} S_{1/2}$ $ϕN$ interaction is obtained from the combination of the $ϕp$ correlation function analysis and the HAL QCD results, as well as from the assumption that the spin-spin parts of the $ϕN$ and $J / ψ N$ interactions are inversely proportional to the respective hadron masses. The Faddeev equations are solved to find bound states in the $J / ψ N N$ and $ϕ N N$ three-body systems. The numerical results suggest that there exist bound states in the $ϕ N N$ three-body system, while there is no bound state in the $J / ψ N N$ system.
↳ hep-phnucl-th0 citations
12
On the nature of fully-charmed four-quark exotic state $X (6900)$ from its photoproduction off nuclei
E. Ya. Paryev
The possibility to study the nature of fully-charmed tetraquark state $X (6900)$ from its inclusive photoproduction off nuclei near the kinematic threshold is investigated within the collision model based on the nuclear spectral function. The model accounts for $X (6900)$ production in direct photon--nucleon interactions as well as three different scenarios for its internal structure: compact tetraquark, molecule of the two hidden-charm $J / ψ$ and $ψ (3770)$ mesons and the mixture of both of them. We calculate within these scenarios the absolute and relative excitation functions on $^{12}$ C and $^{184}$ W nuclei at near-threshold photon energies of 30--40 GeV, the absolute momentum differential cross sections and ratios of them for the $X (6900)$ meson production off these target nuclei at laboratory polar angles of 0 $^{\circ}$ --5 $^{\circ}$ and for photon energy of 35 GeV as well as the A-dependences of its transparency ratios at photon energy of 35 GeV. We show that these observables reveal a definite sensitivity to the $X (6900)$ intrinsic structure. Therefore, they might be useful for the determination of this structure from the comparison of them with the experimental data from the future experiments at the upcoming experimental facilities, such as the planned electron-ion colliders in the United States and China.
↳ hep-phhep-exnucl-exnucl-th0 citations
13
Statistical and non-statistical $γ$ -decay properties of $^{64}$ Zn
A. C. Larsen · M. Guttormsen · T. K. Eriksen · G. M. Tveten · H. Utsunomiya · J. K. Dahl · N. Shimizu · T. Ari-izumi · F. L. Bello Garrote · L. T. Bell · M. M. Bjørøen · F. W. Furmyr and 14 other authors
We present a study on the $γ$ -decay properties of $^{64}$ Zn using the Oslo method on $^{64}$ Zn( $p, p^{'} γ$ ) data combined with $^{64}$ Zn $(γ, n)$ cross-section measurements at the NewSUBARU facility. With the Oslo method, we have measured the $γ$ -ray strength function ( $γ$ SF) and the nuclear level density (NLD) below the neutron threshold. We observe that the NLD trend in the quasi-continuum region of $^{64}$ Zn is best characterized by a constant-temperature-like model. %with temperature parameter $T_{CT} = 1.21 (5)$ MeV. Surprisingly, we find that $γ$ -ray transitions from the quasi-continuum decaying directly to the $0^{+}$ ground state seem to be strongly hindered with a hindrance factor of $κ \approx 0.5$ , which could be an indication of non-statistical effects in the ground-state decay due to, \textit{e.g.}, differences in nuclear shapes. For $γ$ energies above the neutron separation energy, the NewSUBARU ( $γ, n$ ) data set probes a significant part of the giant dipole resonance. Furthermore, we find that the Oslo-method $γ$ SF shows a rather smooth behavior, with a clear low-energy enhancement (LEE) for $E_{γ} < 4$ MeV.
↳ nucl-exnucl-th0 citations

Affiliations

first authorsco-authorsvia INSPIRE

The Momentum Fraction, Helicity and Transversity Isovector Moments of Nucleons from \texorpdfstring{2+1}{2+1}-flavor Lattice QCD

The Utility of Sparse Error Detection in Quantum Simulations

Critical coupling with zero-mode corrections in discretized light-cone quantized ϕ4 theory

Faddeev equations for the J/ψNN and ϕNN three-body systems in momentum space

On the nature of fully-charmed four-quark exotic state X(6900) from its photoproduction off nuclei

Statistical and non-statistical γ-decay properties of 64Zn

Affiliations

The Momentum Fraction, Helicity and Transversity Isovector Moments of Nucleons from \texorpdfstring{ $2 + 1$ }{2+1}-flavor Lattice QCD

Critical coupling with zero-mode corrections in discretized light-cone quantized $ϕ^{4}$ theory

Faddeev equations for the $J / ψ N N$ and $ϕ N N$ three-body systems in momentum space

On the nature of fully-charmed four-quark exotic state $X (6900)$ from its photoproduction off nuclei

Statistical and non-statistical $γ$ -decay properties of $^{64}$ Zn