From Quarks and Gluons to the Internal Dynamics of Hadrons

Contribution List

1. Spin-orbit correlations in QCD

Yoshitaka Hatta

5/15/24, 9:30 AM

I present QCD analyses of the spin-orbit correlation of quarks and gluons inside hadrons. I discuss what we can learn from such correlations and how to access them in experiments at the EIC.

3. Phenomenology of transverse momentum dependent distributions of the pion and proton

Patrick Barry

5/15/24, 10:00 AM

Recent works on pion structures through the JAM framework introduce both Drell-Yan (DY) and leading neutron (LN) electroproduction observables to constrain parton distribution functions (PDFs) in the pion. Extending to the transverse direction, we make use of low energy transverse momentum dependent DY data to extract pion transverse momentum dependent (TMD) PDFs. In these fixed target DY...

4. Status of unpolarized TMD extractions from global fits

Matteo Cerutti (Hampton University and Jefferson Lab)

5/15/24, 11:00 AM

In this talk, we discuss the latest results on the extraction of Transverse-Momentum-Dependent (TMD) distributions from global analyses of presently available experimental data. In particular, we focus on the simultaneous extraction of TMD Parton Distribution Functions (TMD PDFs) and Fragmentation Functions (TMD FFs) from global fits of semi-inclusive DIS and Drell-Yan data sets in the...

5. Gluonic structure of proton from lattice QCD

Raza Sufian

5/15/24, 11:30 AM

We present the first lattice QCD determination of the gluon helicity parton distribution function (PDF) toward ruling out the negative gluon polarization in the nucleon within the mid to large momentum fraction region. Additionally, we highlight the potential synergy between lattice QCD and generative machine learning applications, offering an avenue to explore the diverse systematic...

6. Probing the gluon gravitational form factors of proton using near threshold J/ψ photoproduction

Shivangi Prasad

5/15/24, 12:00 PM

Gravitational form factors (GFFs) encapsulate fundamental information about a hadron's internal structure including its mass distribution and mechanical quantities such as the pressure and shear forces. Recently, significant efforts have been made to access these GFFs experimentally and via ab initio lattice calculations. In this talk, I will focus on measurement of near-threshold $J/\psi$...

9. Proton GPD from lattice QCD

Martha Constantinou

5/15/24, 2:30 PM

Most of the information from lattice QCD is on the Mellin moments of GPDs, namely form factors and their generalizations. Calculating the x-dependence of GPDs from lattice QCD has become feasible in the last few years due to novel approaches. In this work, we employ the approach of quasi-distributions, which relies on matrix elements of fast-moving hadrons coupled to non-local operators. The...

7. Non-perturbative Collins-Soper kernel from a Coulomb-gauge-fixed quasi-TMD with chiral fermions

Xiang Gao

5/15/24, 3:00 PM

We present the first lattice QCD calculation of the rapidity anomalous dimension of transverse-momentum-dependent distributions (TMDs), i.e. the Collins-Soper (CS) kernel, employing the recently proposed Coulomb-gauge-fixed quasi-TMD formalism as well as a chiral-symmetry-preserving lattice discretization. This unitary lattice calculation is conducted using the domain wall fermion...

8. Nucleon transversity and tensor charge from di-hadron production

Andreas Metz

5/15/24, 3:30 PM

We first present a new quantum field-theoretic definition of dihadron fragmentation functions (DiFFs) that have a number density interpretation. We then discuss the first global QCD analysis of dihadron production for a comprehensive set of data in electron-positron annihilation, semi-inclusive deep-inelastic scattering, and proton-proton collisions, from which we extract simultaneously the...

10. Femtoscopy of the matter distribution in the proton

Gastão Krein

5/15/24, 4:30 PM

Femtoscopy measurements of $J/\psi$-proton correlation functions in high-energy hadron collisions can access information on the matter distribution in the proton. The QCD multipole expansion allows us to express the $J/\psi$-proton scattering amplitude in terms of the product of the $J/\psi$ chromopolarizability and a scalar gluon gravitational (GFF) form factor. The scalar gluon GFF gives...

14. Overview of TMD related measurements

Ralf Seidl

5/16/24, 9:30 AM

Transverse momentum dependent distribution and fragmentation functions are relevant in many processes when transverse momenta of final-state particles are observed. They provide additional information on the transverse spin and momentum structure of partons inside the nucleon that can otherwise not be accessed. For example, the Sivers function provides information on the transverse nucleon...

12. A separable Bethe-Salpeter approach to deuteron structure

Adam Freese

5/16/24, 10:00 AM

Motivated by the desire to maintain manifest Lorentz covariance in calculations of deuteron structure, I model the nucleon-nucleon interaction using a non-local separable interaction Lagrangian. The Bethe-Salpeter equation for the deuteron's bound state vertex is separable and solvable in this model. With the deuteron vertex in hand, I calculate the electromagnetic and mechanical structure of...

27. New physical processes for extracting generalized parton distributions with a better sensitivity to partonic structure

Zhite Yu

5/16/24, 11:00 AM

Generalized parton distributions (GPDs) encode important non-perturbative information of hadron structures including the tomographic parton images. We introduce a type of exclusive processes for a better study of GPDs, which we refer to as single diffractive hard exclusive processes (SDHEPs), and give a general argument for their factorization into GPDs. We advocate a two-stage framework for...

16. Experimental search for saturation physics at STAR

Xiaoxuan Chu

5/16/24, 11:30 AM

Nucleons (protons and neutrons), composed of quarks held together by gluons, exhibit rapid growth in gluon density towards small momentum fractions (x). It is expected that this growth is controlled by nonlinear Quantum Chromodynamics (QCD) effects leading to the effect of gluon saturation. Understanding the role of saturated strong gluon fields has motivated tremendous theoretical efforts....

17. Small-x TMD factorization at NLO: semi-inclusive dijets and dihadrons in DIS

Farid Salazar

5/16/24, 12:00 PM

Two-particle azimuthal correlations are an excellent window to access the dynamics of gluon saturation in collider experiments. In the kinematic regime where the two particles are produced sufficiently forward rapidities but back-to-back in the transverse plane, the differential cross-section computed in the Color Glass Condensate (CGC) admits a small-x TMD-like factorization. In this talk, I...

15. QCD spectroscopy and scattering theory on the lattice

Raúl Briceño

5/16/24, 2:30 PM

To gain general principles of QCD from the spectrum and structure of hadrons, it is necessary to look across a broad range of states and see if patterns emerge. This is no small task due to two major obstacles. First, of course QCD is non-perturbative, which can in-principle be overcome with the use of lattice QCD. Second, the vast majority of states are unstable resonances that decay rapidly...

20. Exploring Meson Structures from Lattice QCD

Qi Shi

5/16/24, 3:00 PM

We present a comprehensive study of the electromagnetic form factors (EMFFs) of the pion and kaon, as well as the generalized parton distributions (GPDs) of the pion, using lattice QCD. For the pion and kaon form factors, we compute the pion and kaon EMFFs at high momentum transfers, -t, up to 10 and 28 GeV², respectively, achieving good agreement with experimental results up to -t ≲ 4$ GeV²...

18. Signatures of the Yang-Mills deconfinement transition from the gluon two-point correlator

Duifje van Egmond

5/16/24, 3:30 PM

The breaking of center symmetry in pure Yang-Mills theories has been connected to the confinement/deconfinement transition on the lattice, but continuum results did not show the same signatures. I will discuss the longitudinal or (chromo-)electric Yang-Mills gluon propagator in the recently proposed center-symmetric Landau gauge at finite temperature. We use the Curci-Ferrari model which...

19. TMD factorization unifying large and small x

Andrey Tarasov

5/16/24, 4:30 PM

21. Hadron structure from the lattice Compton amplitude

Gerrit Schierholz

5/16/24, 5:00 PM

Experimentally, hadron structure functions are extracted from the forward and off-forward Compton amplitudes. On the other hand, theoretical calculations are limited to Euclidean space-time. The closest one can come to exploiting the full potential of the EIC is to compute the Compton amplitude on the lattice in full diversity. In this talk I will discuss the challenges and the potential of...

23. Transverse Momentum Distributions from Lattice QCD without Wilson Lines

Yong Zhao

5/17/24, 9:30 AM

The transverse-momentum-dependent distributions (TMDs), which are defined by gauge-invariant 3D parton correlators with staple-shaped lightlike Wilson lines, can be calculated from quark and gluon correlators fixed in the Coulomb gauge on a Euclidean lattice. These quantities can be expressed gauge-invariantly as the correlators of dressed fields in the Coulomb gauge, which reduce to the...

24. Lattice QCD calculation of the pion distribution amplitude with domain wall fermions at physical pion mass

Rui Zhang

5/17/24, 10:00 AM

Pion distribution amplitude (DA) describes the wave function of pion as a quark-antiquark pair in the infinite-momentum frame. It has rich phenomenology due to its universality as inputs to exclusive processes and form factors at large momentum transfer.
In this talk, I will present our recent lattice QCD calculation of pion DA on a chiral-symmetric domain-wall fermion ensemble at physical...

13. Insights into the cold QCD medium

Charles-Joseph Naïm

5/17/24, 11:00 AM

Abstract: Understanding the effects of cold nuclear matter (CNM) is still a puzzle, especially in terms of their magnitude. These effects vary depending on the hard process, impacting the rapidity and transverse momentum distributions of the dilepton. Deciphering CNM effects is crucial for comprehending suppressions observed in hA collisions from fixed targets to LHC energies, but also in...

28. Unraveling the internal structure of hadrons: from form factors to generalized parton distributions and future directions

Melany Higuera Angulo

5/17/24, 11:30 AM

We present our extensive investigation into the internal structure of hadrons, particularly pseudo-scalar mesons, utilizing a unified algebraic model based on Schwinger-Dyson equations (SDEs). We showcase calculations of various non-perturbative objects, including electromagnetic (EFFs), transition form factors (TFFs), parton distribution functions (PDFs), generalized parton distributions...

22. Nuclear-modified transverse momentum distribution functions

John Terry

5/17/24, 12:00 PM

For more than 50 years, bound hadrons have been known to undergo non-trivial modifications due to the presence of the cold nuclear medium."During this time, experimental measurements at collider facilities have focused on how the one-dimensional structure of hadrons is modified, with global QCD analyses proving extremely successful in extracting these distributions. More recently, we have used...

26. Hadronization dynamics from the spectral representation of the gauge invariant quark propagator

Caroline Costa

5/17/24, 2:30 PM

It is well known that a gauge dependent two-point correlation function can be made gauge invariant by introducing a gauge link connecting the fields. This stringy ansatz is widely used to build gauge invariant observables in DIS, as for instance, parton distribution functions (PDFs) and transverse-momentum-dependent functions (TMDs). In this talk, I will discuss recent results connecting the...

30. Gravitational form factors from lattice QCD

Dimitra Pefkou

5/17/24, 3:00 PM

31. Multi-dimensional analyses of spin asymmetries

Gunnar Schnell

5/17/24, 4:00 PM

One of the challenges faced in the analysis of semi-inclusive processes, like semi-inclusive deep-inelastic scattering, is the richness of the cross section with multi-dimensional dependence on various kinematic variables. The fully differential cross section of even just unpolarized lepton-nucleon scattering already requires at least five dimensions (single-hadron production) and even more so...

2. Novel reactions to access Generalized Parton Distributions in dilepton pairs

Marie Boër

5/17/24, 4:30 PM

32. Threshold resummation for the virtual Compton process

Jakob Schoenleber

5/17/24, 5:00 PM

I explain how to resum the threshold x -> +-xB logarithms in the hard coefficient function for the virtual Compton process in momentum space. This is the off-forward generalization of the threshold resummation in DIS in the endpoint xB -> 1 region. The interesting case is that of an outgoing real photon, i.e. DVCS, where the threshold limit corresponds to the limit of zero parton momenta x ->...

29. Large computation efforts in nuclear physics

Ian Cloët