Conveners
Structure of hadrons and nuclei
- Rui Zhang (University of Maryland)
Structure of hadrons and nuclei
- Yong Zhao
Structure of hadrons and nuclei
- Frank Winter (Jefferson Lab)
Structure of hadrons and nuclei
- Yang Fu (MIT)
Structure of hadrons and nuclei
- Michael Engelhardt
Structure of hadrons and nuclei
- Jonna Marjaana Koponen (Bergische Universitรคt Wuppertal)
Structure of hadrons and nuclei
- Joseph Karpie
Structure of hadrons and nuclei
- Christian Zimmermann (University of Kentucky)
Structure of hadrons and nuclei
- Fangcheng He
Structure of hadrons and nuclei
- Raza Sufian (New Mexico State University / BNL)
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227. Parton Distribution Functions of the Nucleon from Twisted Mass Fermions with Physical Pion MassGabriele Pierini (The Cyprus Institute, TU Berlin)27/07/2026, 14:00Structure of hadrons and nucleiContributed talk
We present the unpolarized and helicity Parton Distributions (PDFs) of the nucleon using an ensemble of $N_f$=2+1+1 twisted mass clover-improved fermions with masses tuned to their physical values and lattice spacing of $a=0.080$ fm. We analyze seven momentum boosts up to $P_z=1.69$ GeV. At boost $P_z=1.21$ GeV we analyze three source-sink separations, in order to investigate possible excited...
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Prof. Martha Constantinou27/07/2026, 14:201Structure of hadrons and nucleiContributed talk
We present a calculation of the $x$ dependence of quark GPDs for the nucleon using an ensemble of $N_f$=2+1+1 twisted mass clover-improved fermions with masses tuned to their physical values and a lattice spacing of $a=0.080$ fm. We use matrix elements of nonlocal operators at several values of the momentum boost up to 1.69 GeV, enabling the extraction of GPDs in both the large-momentum...
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Manuel Colaรงo (Adam Mickiewicz University)27/07/2026, 14:40Structure of hadrons and nucleiContributed talk
This talk presents an extraction of Mellin moments of the proton unpolarized generalized parton distributions (GPDs) at nonzero skewness from lattice QCD. The analysis builds on the recent studies of GPDs at nonzero skewness, which, together with the polynomiality relations and short-distance factorization matching, connect the moments to generalized form factors. The present method uses...
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Jack Holligan27/07/2026, 15:00Structure of hadrons and nucleiContributed talk
Large-momentum effective theory (LaMET) allows for a direct calculation of $x$-dependent generalized parton distributions (GPDs) with skewness value $\xi$ on the Euclidean lattice. Large logarithms become present in the lightcone matching process as the momentum fraction of the studied parton approaches 1. We demonstrate a method of resummation for such logarithms as well as provisional...
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Christian Kummer27/07/2026, 15:20Structure of hadrons and nucleiContributed talk
Nucleon Mellin moments of parton distribution functions and generalized parton distributions are computed up to the fourth order in lattice QCD. The computation is performed using one ensemble of twisted mass fermions at the physical pion mass point. We employ boosted frames to access the higher-order Mellin moments of generalized parton distributions. We also extract the generalized...
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Joshua Miller27/07/2026, 16:10Structure of hadrons and nucleiContributed talk
In recent years, methods such as large momentum effective theory (LaMET) and short distance factorization (SDF) have allowed us to extract the $x$-dependence of parton distribution functions (PDFs) utilizing non-local operators of a boosted hadron. Contained within the PDFs is information on fundamental hadronic properties, such as the fraction of the hadron momentum carried by quarks, which...
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Joseph Torsiello (Temple University)27/07/2026, 16:30Structure of hadrons and nucleiContributed talk
We present a calculation of the $x$ dependence of unpolarized quark GPDs for the pion and kaon on an $N_f=2+1+1$ ensemble of maximally twisted-mass fermions with a clover term, with lattice volume $32^3\times64$, lattice spacing $a=0.0934$ fm, and pion mass $m_\pi=260$ MeV. The matrix elements contain boosted hadrons coupled to nonlocal operators and are computed for momentum boosts up to 2...
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S.-P. Alex Chang (Institute of Physics, National Yang Ming Chiao Tung University)27/07/2026, 16:50Structure of hadrons and nucleiContributed talk
The light-cone distribution amplitude (LCDA) is a non-perturbative quantity for understanding hadron structure and exclusive scattering processes. We present our calculation of moments of the pion and kaon LCDAs using the heavy-quark operator product expansion (HOPE) framework. This method employs an OPE analysis of hadronic amplitudes through the inclusion of a fictitious valence heavy...
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Nabil Humphrey27/07/2026, 17:10Structure of hadrons and nucleiContributed talk
Spin-1 deep-inelastic scattering targets admit four tensor-polarised structure functions $b_1$โ$b_4$ in addition to those of spin-1/2 systems. We present a theoretical framework for the extraction of the tensor-polarised structure functions of general spin-1 systems from the Compton amplitude calculated using the FeynmanโHellmann method, while accounting for the contamination from certain...
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Wayne Morris (National Yang Ming Chiao Tung University)28/07/2026, 14:00Structure of hadrons and nuclei
The Collins-Soper kernel is a key, universal quantity that relates transverse momentum dependent distributions (TMDs) at different rapidity scales through an evolution equation. The CS kernel may be obtained through the TMD soft function by formulating the Wilson line in terms of 1-dimensional auxiliary fermion fields on the lattice. The complex auxiliary field directional vectors can be...
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Artur Avkhadiev28/07/2026, 14:201Structure of hadrons and nucleiContributed talk
This talk will present the first nonperturbative constraints on the gluonย (CS) Collins-Soper kernel โ a universal anomalous dimension of transverse-momentum-dependent gluon distributions โ in the range of transverse momentum scales $q_{T} \in [300\text{ MeV}, 1.3\text{ GeV}]$. The constraints are obtained with lattice QCD at a close-to-physical pion mass $M_\pi = {172(3)}\text{ MeV}$, a single...
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Yang Fu (MIT)28/07/2026, 14:401Structure of hadrons and nucleiContributed talk
We will present preliminary results on a lattice QCD study of the gluon Collins-Soper kernel using Coulomb-gauge gluon operators. This kernel governs the rapidity evolution of transverse-momentum-dependent gluon distributions and is nonperturbative at small transverse momentum. The calculation is performed at near-physical pion mass and shows improved statistical precision with this approach.
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Jinchen He (University of Maryland)28/07/2026, 15:002Structure of hadrons and nucleiContributed talk
We present the first lattice-QCD determination of isovector proton transverse-momentum-dependent parton distribution functions (TMDPDFs) simultaneously in the unpolarized, helicity, and transversity channels. The calculation is performed within large-momentum effective theory using Coulomb-gauge-fixed quasi-TMD correlators on a $2+1$-flavor domain-wall fermion ensemble at the physical pion...
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Jyn Peyton (New Mexico State University)28/07/2026, 15:201Structure of hadrons and nucleiContributed talk
One of the foremost goals of research into Quantum Chromodynamics (QCD) is to quantify the internal structure of the proton from first principles. Ab initio calculations of QCD matrix elements like transverse momentum distributions (TMDs) using lattice QCD are an essential part of achieving that goal. I present first explorations of effects on TMDs induced by the more intricate color flows in...
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Alex Sturzu (William and Mary)28/07/2026, 16:10Structure of hadrons and nucleiContributed talk
We present our recent results for the gluon momentum fraction of the nucleon using lattice quantum chromodynamics (QCD), with a nonperturbative renormalization technique based on the gradient flow. Various techniques are used to reduce statistical and systematic uncertainties. The variational method is used to reduce excited-state contamination. Distillation is employed to reduce the costs...
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William Good (Michigan State University)28/07/2026, 16:302Structure of hadrons and nucleiContributed talk
Gluon parton distribution functions (PDFs) from large momentum effective theory (LaMET) have remained in poor statistical precision compared to non-singlet PDFs due to their correlators coming solely from disconnected diagrams. One method to improve the long distance signal is to remove the Wilson lines from the correlators, which are present solely to maintain gauge invariance, and compute...
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Sicheng Liu (stony brook)28/07/2026, 16:501Structure of hadrons and nucleiContributed talk
Gluon generalized parton distributions (GPDs) are important quantities for understanding the three-dimensional structure of hadrons. They encode information about the spatial distribution of gluons, as well as the mass and spin structure of hadrons, and provide access to the gluon contribution to orbital angular momentum, which is at the heart of the proton spin puzzle. In this talk, I will...
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Dr Gregoris Spanoudes (University of Cyprus)28/07/2026, 17:102Structure of hadrons and nucleiContributed talk
We apply the Wilson-flow framework in lattice perturbation theory to study the renormalization of non-singlet twist-two quark bilinear operators containing up to five covariant derivatives. These operators are relevant for the determination of the first six moments of parton distribution functions. In our analysis, we derive the relevant Feynman rules by solving the lattice gauge and fermion...
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Yamil Cahuana Medrano (William and Mary)29/07/2026, 09:00Structure of hadrons and nucleiContributed talk
Extracting parton distribution functions (PDFs) from Lattice QCD is crucial for understanding nucleon structure, but it fundamentally relies on solving a challenging ill-posed inverse problem. In this talk, I will present an overview of my work on addressing this problem within the pseudo-PDF framework. First, I will outline how Gaussian processes (GPs) provide flexible Bayesian priors that...
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Qi Shi (Kent State University)29/07/2026, 09:201Structure of hadrons and nucleiContributed talk
We present a lattice QCD calculation of the nucleon unpolarized parton distribution functions (PDFs) at the physical point, with the nucleon boosted to $P_z = 1.78$ and $2.29$ GeV. At a lattice spacing $a = 0.076$ fm, these momenta correspond to $a P_z \lesssim 0.9$, so that lattice-discretization artifacts remain under control, in contrast to earlier physical-mass studies that reached larger...
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Dr Rui Zhang (MIT)29/07/2026, 09:403Structure of hadrons and nuclei
Coulomb-gauge quasi-parton distributions can be computed directly in momentum space on a finite lattice, enabled by the commutativity of their renormalization and Fourier transform. This approach removes the formal inverse problem in coordinate-space methods. Our momentum-space pion quasi-distributions agree with coordinate-space results Fourier transformed with asymptotic extrapolation,...
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Alex NieMiera (Michigan State University)29/07/2026, 10:002Structure of hadrons and nucleiContributed talk
Iโโn this work, we develop a unified machine learning strategy based on a variational autoencoder inverse mapper (VAIM) to explore the complementarity of the quasi-PDF and pseudo-PDF methodologies. VAIM is a conditional variational autoencoderโbased framework that learns a low-dimensional latent representation of nonperturbative QCD information and constructs an inverse map from...
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Joseph Karpie29/07/2026, 10:202Structure of hadrons and nucleiContributed talk
Femtography is the study of 3D femtometer scale images of the proton. Impact Parameter Distributions describe parton structure in terms of the parton's fraction of the total momenta and the location in the transverse plane. These images can be taken by Deeply Virtual Compton Scattering and other inclusive processes and give light on how mass, angular momentum, and mechanical properties are...
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Christian Zimmermann (University of Kentucky)29/07/2026, 11:10Structure of hadrons and nucleiContributed talk
The hadronic tensor is the central non-perturbative object in the calculation of the cross section of lepton-hadron interactions like neutrino-nucleon scattering. It is parameterized in terms of structure functions, which encode all necessary information independently of the kinematic region. We calculate correlation functions of two currents with Euclidean time separation using a clover...
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Jordan Mckee29/07/2026, 11:30Structure of hadrons and nucleiContributed talk
Precision determinations of $V_{ud}$ from superallowed nuclear ฮฒ decays provide an important test of the Standard Model. A leading theoretical uncertainty arises from electroweak radiative corrections, in particular the contribution from the $\gamma W$ box diagram involving the interference between the electromagnetic and axial currents. The closely related $\gamma Z$ box contribution may be...
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Yong Zhao29/07/2026, 11:501Structure of hadrons and nucleiContributed talk
We present lattice QCD calculations of the proton isovector quark helicity parton distribution function (PDF) within the Large Momentum Effective Theory (LaMET) framework, together with the first determination of the twist-3 moment $\tilde{d}_2$ from the operator product expansion of nonlocal matrix elements. The helicity PDF is calculated using both gauge-invariant (GI) and Coulomb-gauge (CG)...
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Prof. Kehfei Liu (Lawrence Berkeley National Lab)29/07/2026, 12:101Structure of hadrons and nucleiContributed talk
It has been taken for granted in lattice formulation that, due to translational invariance, it is not feasible to have a reference point to define the spatial densities of local operators in a hadron. We shall show that, using Ward identity, one can find the positions of valence quarks so that the spatial densities can be defined and calculated. This bypasses the usual practice of obtaining...
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Constantia Alexandrou30/07/2026, 14:001Structure of hadrons and nucleiContributed talk
We determine the complete spin and momentum fraction decomposition of the nucleon at the continuum limit and compare with phenomenological analyses.
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The computation is done using four twisted mass ensembles with different lattice spacings and physical pion mass.
The renormalization functions are computed fully non-perturbatively including the mixing between the singlet quark and gluon... -
Masato Nagatsuka (Tohoku University)30/07/2026, 14:20Structure of hadrons and nucleiContributed talk
This study uses the third PACS10 gauge ensemble generated by the PACS Collaboration, providing a large physical volume exceeding $(10\,\mathrm{fm})^4$. This large volume is highly advantageous for determining detailed form factors in the small-$q^2$ region, where the root-mean-square radius, i.e., the axial radius, can be more precisely evaluated. The resulting nucleon axial-vector form factor...
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Sungwoo Park (Sejong University)30/07/2026, 14:402Structure of hadrons and nucleiContributed talk
Results from ongoing calculations of the nucleon isovector electromagnetic form factors by the PNDME collaboration are presented. These are based on data from $\mathcal{O}(7000)$ configurations on two physical pion mass ensembles with $2+1+1$-flavor HISQ generated by the MILC collaboration at lattice spacings $a=0.087$ and $a=0.0576$ fm. We will discuss the extraction of the electric and...
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Prof. Sergey Syritsyn (Stony Brook University)30/07/2026, 15:00Structure of hadrons and nucleiContributed talk
Proton and neutron electric and magnetic form factors are the primary characteristics of their spatial structure and have been studied extensively over the past half-century. At large values of the momentum transfer $Q^2$ they should reveal transition from nonperturbative to perturbative QCD dynamics and effects of quark orbital angular momenta and diquark correlations. Currently, these form...
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Joshua Crawford (University of Wuppertal)30/07/2026, 15:20Structure of hadrons and nucleiContributed talk
The calculation and analysis of nucleon correlation functions is essential for understanding the observed spectra and structure of these ubiquitous hadrons. Two challenges arise in their analysis: at early Euclidean times, they are dominated by excited state contributions, and at later Euclidean times, the signal-to-noise ratio is too great to extract meaningful physics. This leads to a common...
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Lorenzo Barca (DESY)30/07/2026, 16:101Structure of hadrons and nucleiContributed talk
Nucleon sigma terms are important for the decomposition of the nucleon mass and for searches for new physics beyond the Standard Model involving scalar interactions. A persistent tension between lattice QCD and phenomenological determinations may be due to uncontrolled excited-state contamination in lattice QCD analyses. In previous work at $m_\pi=429$ MeV, we showed that this contamination is...
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Pia Leonie Jones Petrak (JLab)30/07/2026, 16:301Structure of hadrons and nucleiContributed talk
Sigma terms are of fundamental interest as measures of the quark mass contributions to the mass of a given baryon. As the key input for neutrino and nucleon cross-sections, the nucleon sigma terms are relevant for dark matter predictions. Further, for the nucleon-pion sigma a long standing discrepancy between Lattice QCD and phenomenology persists. By performing a direct determination of the...
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Rohith Karur (The University of California, Berkeley)30/07/2026, 16:50Structure of hadrons and nucleiContributed talk
Nucleon sigma terms quantify the contributions of scalar quark condensates towards the nucleon's mass. Aside from understanding the origins of the various components of the nucleon's mass, these scalar matrix elements strongly affect the magnitude of certain dark matter (WIMP) - nucleon scattering cross sections. Their precise theoretical determination could thus offer input into the...
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Christian Schneider (University of Cyprus)30/07/2026, 17:10Structure of hadrons and nucleiContributed talk
The inclusion of isospin-breaking corrections arising from electromagnetic interactions and the upโdown quark mass difference has become timely in modern lattice QCD calculations, as the precision of many observables has reached the percent level. In this context, the RM123 method has played a pivotal role in recent years. In this work, we apply this framework to the study of baryon mass...
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Vaibhav Chahar (Jagiellonian University, Poland)31/07/2026, 14:00Structure of hadrons and nucleiContributed talk
The instanton liquid model is believed to capture the main features of vacuum QCD dynamics. Recently, multiple predictions for hadron structure functions have been derived and compared with experimental measurements and lattice QCD calculations, showing general agreement. In order to explore the precision of the instanton liquid model, one has to compare its predictions with non-perturbative...
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Kohei Sato (Center for Computational Sciences, University of Tsukuba)31/07/2026, 14:20Structure of hadrons and nucleiContributed talk
We report a preliminary study of light meson charge radii based on the PACS10 configurations generated by the PACS Collaboration at the physical point in spatial volumes larger than $(10\,\text{fm})^3$. Lattice QCD calculations of charge radii are generally subject to several sources of systematic uncertainty, including chiral extrapolation, discretization effects, finite-volume effects, and...
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sudip shiwakoti (Baylor University)31/07/2026, 14:40Structure of hadrons and nucleiContributed talk
The electric and magnetic polarizability of hadrons encodes information on their internal structure. Traditionally, the background field method has been used to calculate polarizabilities. However, recent work has demonstrated the effectiveness of using four-point functions for computing polarizabilities of charged and neutral hadrons. Our previous work employed a quenched Wilson action on a...
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Dr Antonio Evangelista (University of Cyprus)31/07/2026, 15:001Structure of hadrons and nucleiContributed talk
In this talk, we present a study of the performance of low-mode averaging (LMA) techniques on twisted-mass fermion ensembles at near-physical quark masses, assessing both their theoretical foundations and practical cost-effectiveness in contemporary lattice QCD. We focus on light-quark meson and baryon observables and perform a detailed numerical investigation of the resulting variance...
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Raza Sufian (New Mexico State University / BNL)31/07/2026, 15:202Structure of hadrons and nucleiContributed talk
Photons can acquire a hadronic structure through quantum fluctuations, effectively becoming a superposition of the $U(1)$ gauge boson of QED and QCD quark-gluon configurations. Consequently, in electron-proton scattering, partons from both the resolved photon and proton can participate in strong interactions, revealing the resolved photon's hadronic structure. Although this nonperturbative...
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Geng Li31/07/2026, 16:10Structure of hadrons and nucleiContributed talk
We carry out the first lattice calculation of the charm quark density-density correlations for $1S$ and $1P$ conventional charmonia, as well as charmoniumlike states $\eta_{c1}(1^{-+})$ and $h_{c0}(0^{+-})$, which provide {\it ab initio} information about the internal spatial structures of these states. The spatial distributions of the charm quark and antiquark ($c\bar{c}$) in $1S$ and $1P$...
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Jonna Marjaana Koponen (Bergische Universitรคt Wuppertal)31/07/2026, 16:30Structure of hadrons and nucleiContributed talk
Over the past decades a number of resonances have been discovered, mostly in the charm sector, that do not fit into a simple quark model picture. A rigorous understanding of how these states arise from QCD and how they can be classified is required, which can only be attained in conjunction with advances in the calculational methods.
In addition to the study of masses and widths of stable...
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Anton Shcherbakov31/07/2026, 16:50Structure of hadrons and nucleiContributed talk
We will provide an update to the RBC-UKQCD collaborations on the lattice calculation of the position-space, long-distance $\pi^0$ exchange part of the HLbL contribution to the anomalous magnetic moment of the muon. We will present the results of the calculation from 48I and 64I gauge-field ensembles at $a^{-1}=1.73$ GeV and $a^{-1}=2.359$ GeV, respectively. Additionally, we will present the...
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Manuel Schneider (National Yang Ming Chiao Tung University)31/07/2026, 17:10Structure of hadrons and nucleiContributed talk
The rich internal structure of hadrons is encoded in partonic functions, such as parton distribution functions (PDFs) and light-cone distribution amplitudes (LCDAs), which are crucial in collider experiments and decay processes. Calculating them from first principles remains a major challenge: they require matrix elements with a Wilson line along a light-like direction, which are not directly...
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