QCD Evolution 2025

Session

Parallel II

May 19, 2025, 2:00 PM

Conveners

Parallel II: Parallel II

• Adam Freese (Jefferson Lab)

Parallel II: Parallel II

• Marco Zaccheddu (Jefferson Lab)

Parallel II: Parallel II

• There are no conveners in this block

Parallel II: Parallel II

• There are no conveners in this block

Parallel II: Parallel II

• There are no conveners in this block

Parallel II: Parallel II

• There are no conveners in this block

Parallel II: Parallel II

• There are no conveners in this block

31. Quark and Gluon GPD Global Analysis with DVCS and DVMP at NLO

Fatma Aslan (JLab)

5/19/25, 2:00 PM

We use the GUMP (Generalized Parton Distributions (GPDs) through Universal Moment Parametrization) framework, based on the conformal moments of GPDs, to perform a unified global analysis incorporating Deeply Virtual Compton Scattering (DVCS) and Deeply Virtual Meson Production (DVMP) data. By performing simultaneous fits across these processes and incorporating Next-to-Leading Order (NLO)...

33. Likelihood Analysis of Helicity Configurations from Deeply-Virtual Compton Scattering Experiments

Kemal Tezgin

5/19/25, 2:30 PM

There is a wealth of information encoded in Generalized Parton Distributions (GPDs) to describe the three-dimensional structure of the nucleon. Deeply Virtual Compton Scattering (DVCS) experiments play a crucial role in accessing these distributions, providing a direct link to the spatial and momentum structure of partons inside the nucleon. The DVCS cross-section is commonly expressed either...

34. Probing the Proton's Correlated Spatial Structure Through Exclusive Processes

Panjsheeri Zaki

5/19/25, 3:00 PM

Generalized parton distributions (GPDs) serve as indispensable tools in filling in the gaps of the angular momentum sum rules as well as mapping the partonic spatial structure of hadrons. In this work, we extend the utility of GPDs in mapping the proton’s spatial structure beyond the typical one-body partonic picture, obtainable through Fourier transformations of GPDs to impact parameter...

32. Progress Towards the Extraction of GPDs Utilizing Machine Learning

Eric Moffat (Argonne National Lab)

5/19/25, 4:00 PM

I will present recent progress on the extraction of GPDs from data utilizing machine learning.

60. The Ecology of Uncertainty: Capturing Epistemic Doubt in Hadron Structure Analyses

Brandon Kriesten (Argonne National Lab)

5/19/25, 4:30 PM

Inverse problems are ubiquitous in hadron structure and tomography, where accurately characterizing uncertainties is crucial for unraveling new physics hiding within these uncertainties. In this new precision era of QCD, it is vital to create a translation between our physics and next generation AI/ML algorithms, using tools such as evidential deep learning and information-theoretic metrics to...

41. Upgrading the Knowledge on TMD Distributions in the Proton

Matteo Cerutti (Hampton University and Jefferson Lab)

5/20/25, 2:00 PM

The understanding of the three-dimensional internal structure of the proton has significantly been developed over the past few decades. In particular, the extraction of Transverse Momentum Dependent distributions (TMDs) from global fits of experimental data has now reached an impressive level of precision. In this talk, I will present first indications of flavor dependence emerging from the...

42. Towards a Pixel-Based Imaging of TMDs Distribution Functions

Marco Zaccheddu (Jefferson Lab)

5/20/25, 2:30 PM

38. On the partonic structure of hadrons from low to high transverse-momentum

Leonard Gamberg (Penn State Berks)

5/20/25, 3:30 PM

44. New Insights into Lambda Fragmentation Functions

Alessia Bongallino (Universidad del País Vasco UPV/EHU)

5/20/25, 4:00 PM

In this talk I present a new determination of the unpolarised fragmentation functions (FFs) for Lambda production from single-inclusive e+e- annihilation, semi-inclusive deep-inelastic scattering and pp collisions data. The analysis is done at both next-to-leading order (NLO) and next-to-next-to-leading order (NNLO). We extract the unpolarised FFs defining a parametrisation in terms of a...

43. Energy Independence of the Collins Asymmetry in pp Collisions at STAR

Yixin Zhang (Shandong University)

5/20/25, 4:30 PM

Study of the origin of transverse single-spin asymmetries has triggered the development of the twist-3 formalism and the transverse-momentum-dependent parton distribution functions (TMDs). Measurement of the azimuthal distribution of identified hadrons within a jet in transversely polarized hadronic interactions provides an opportunity to study the TMD physics in the final state, {\it i.e.},...

51. Entanglement as a Probe of Hadronization

Charles Joseph Naїm (Stony Brook University (CFNS))

5/22/25, 2:00 PM

52. Quark TMDs from back-to-back Dijet pPduction at Forward Rapidities in pA Collisions beyond Eikonal Accuracy in the CGC

Etienne Bianco

5/22/25, 2:30 PM

We study dijet production in pA collisions at forward rapidities at next-to-eikonal accuracy. We restrict ourselves to the next-to-eikonal corrections that are induced by the quark background field of the target. Computing the scattering amplitudes, for all possible channels, in the back-to-back limit allows the study of leading twist quark TMDs in the high energy limit. We indeed express the...

53. Probing Hadronization and Quark-Gluon Plasma Using Collinear-Drop Jet Observables

Oleh Fedkevych (Georgia State University)

5/22/25, 3:00 PM

54. Proton Spin from Small-x With Constraints from the Valence Quark Model

Daniel Adamiak (Ohio State University)

5/22/25, 4:00 PM

We apply the valence quark model to constrain the non-perturbative initial condition for the small-x helicity evolution. The remaining free parameters are constrained by performing a global analysis to the available polarized small-x deep inelastic scattering data. A good description of the world data is obtained with only 8 free parameters. The model parameters are tightly constrained by the...

55. Effects of Threshold Resummation for Large-x PDF in Large Momentum Effective Theory

Yushan Su (UMD)

5/22/25, 4:30 PM

Parton distribution functions (PDFs) at large $x$ are challenging to extract from experimental data, yet they are essential for understanding hadron structure and searching for new physics beyond the Standard Model. Within the framework of the large momentum $P^z$ expansion of lattice quasi-PDFs, we investigate large $x$ PDFs, where the matching coefficient is factorized into the hard kernel,...

61. Meson electroproduction at very high transverse momentum

Carl Carlson (William & Mary)

5/23/25, 2:00 PM

When electrons strike a proton or nuclear target, there is a regime where electroproduction of the highest momentum pion or rho mesons proceeds by a perturbatively calculable process. The process is not the leading twist fragmentation process but rather a higher twist process that produces kinematically isolated mesons. Our calculations demonstrate, that in conditions that can be expected at...

62. Two-Photon-Exchange Effects for the Azimuthal Asymmetries of SIDIS Cross Section

Andrei Afanasev (GWU)

5/23/25, 2:30 PM

Calculations of the QED corrections to semi-inclusive deep-inelastic scattering (SIDIS) are crucial for studies of the 3D structure of the nucleon at JLab and future Electron Ion Collider (EIC). Previously, the important role of two-photon exchange (TPE) was discovered for the studies of nucleon structure in elastic electron-proton scattering. Here, we address the role of TPE corrections on...

64. Quantum Algorithms for High Energy Evolution

Shaswat Tiwari (North Carolina State University)

5/23/25, 3:00 PM

35. TBA

Singh Ravi

We compute the contribution of the quark and gluon component of the energy-momentum tensor (EMT) to the angular momentum density in various decompositions. We use the light-front Hamiltonian technique, and a two-component formalism in light-front gauge, where the constrained degrees of freedom are eliminated. Instead of a nucleon, we consider a simple composite spin-1/2 state, namely a quark...

45. TBA

Filippo Delcarro (University of Pavia)

63. TBA

Sudeep Saha

My work focuses on trying to understand the mechanical properties of nucleons, such as mass, angular momentum, pressure, and shear force distribution, in terms of their quark and gluon constituents. In this work, we calculate the pressure and shear force distributions using the matrix elements of the energy-momentum tensor, which can be parametrized in terms of gravitational form factors. We...