Conveners
Parton and Gluon Distributions in Nucleons and Nuclei: Parallel 5 — Parton Helicities and the Spin Sum Rule
- Ralf Seidl (RIKEN)
Parton and Gluon Distributions in Nucleons and Nuclei: Parallel 7 — Unpolarized PDFs
- Ralf Seidl (RIKEN)
Parton and Gluon Distributions in Nucleons and Nuclei: Parallel 8 — Transverse Spin Structure and Fragmentation
- Ralf Seidl (RIKEN)
Parton and Gluon Distributions in Nucleons and Nuclei: Parallel 9 — Exclusive Physics and Future
- Ralf Seidl (RIKEN)
Prof.
Keh-Fei Liu
(University of Kentucky)
5/31/18, 2:00 PM
PGDNN
Parallel
The formulation of the glue spin operator and large momentum effective theory will be reviewed and a direct calculation of the glue spin from the lattice calculation with chiral fermion action will be presented. The lattice calculation is carried out with overlap fermion on 2+1 flavor domain wall fermion configurations. Both the overlap and domain wall fermions are chiral fermions. A global...
Dr
Ming Liu
(Los Alamos National Laboratory)
5/31/18, 2:30 PM
PGDNN
Parallel
The Relativistic Heavy Ion Collier (RHIC) at Brookhaven National
Laboratory has been in operation since 2001 and delivered the world’s
highest energy polarized proton-proton collisions with the center of
mass energy up to 510 GeV. This has provided a unique opportunity to
study the polarized quark and gluon spin structures inside the proton
and novel QCD dynamics in longitudinally and...
Alexandre Deur
(Jefferson Lab)
5/31/18, 3:00 PM
PGDNN
Parallel
We will summarize the longitudinal and transverse spin measurements at JLAB. First, we will present the published and preliminary experimental results. They belong to a first phase of research using JLab's 6 GeV beam that covered the interface between the perturbative and nonperturbative domains of QCD. Furthermore, we have results pertaining to these two domains, e.g. high-$x$ DIS on one side...
Mr
Nicolas PIERRE
(CEA Saclay)
5/31/18, 3:20 PM
PGDNN
Parallel
COMPASS final results on multiplicities of charged hadrons and of identified pions and kaons produced in the deep inelastic muon scattering off an isoscalar target are presented and compared to HERMES results. Measurements are done in bins of $x$, $y$ and $z$ in a wide kinematic range. The hadron and pion data show a good agreement with (N)LO QCD expectations. The most interesting is the kaon...
Dr
Emanuele Roberto Nocera
(Higgs Centre for Theoretical Physics)
6/1/18, 2:00 PM
PGDNN
Parallel
I review recent progress in the determination of the unpolarised parton distribution functions (PDFs) of the proton. I focus on how the needs for accuracy and precision in current and future programs at high-energy accelerators are addressed in contemporary PDF sets. I discuss the impact on PDFs of the uncertainties coming from the data, the theory and the methodology, and I outline some...
Dr
Marco Guzzi
(Kennesaw State University)
6/1/18, 2:30 PM
PGDNN
Parallel
We investigate the possibility of a (sizable) nonperturbative contribution to the charm parton distribution function (PDF) in a nucleon, theoretical issues arising in its interpretation, and its potential impact on LHC scattering processes. We discuss separation of the universal component of the nonperturbative charm from the rest of the radiative contributions and estimate its magnitude in...
Dr
Paul E Reimer
(Argonne National Laboratory)
6/1/18, 2:50 PM
PGDNN
Parallel
To investigate the sea-quark asymmetry of the proton, the SeaQuest experiment at Fermilab uses a proton beam of 120 GeV/c interacting with liquid Hydrogen or Deuterium. Alongside of that the SeaQuest also probes the quark energy loss and EMC effect using targets of Iron, Carbon and Tungsten. Data taking ended in July of 2017, having recorded dimuon events from $1.4 \times 10^{18}$ protons...
Dr
Soumya Mohapatra
(Columbia University)
6/1/18, 3:10 PM
PGDNN
Parallel
Measurements of isolated prompt photon, massive electroweak boson, and jet production in small collision systems are of great interest to understanding the partonic structure of heavy nuclei, and serve as a constraint on the initial state in larger collision systems. These channels are sensitive to a variety of effects such as the modification of the parton densities in nuclei, including the...
Dr
Andrea Signori
(Jefferson Lab)
6/1/18, 4:10 PM
PGDNN
Parallel
Uncertainties generated by our ignorance of hadronic structure hamper precision calculations for high-energy scattering processes.
Transverse-momentum-dependent (TMD) distributions give a quantitative representation of hadronic structure in a three-dimensional momentum space and encode all the possible spin and momentum correlations between a hadron and its constituents.
Extractions of TMDs...
Oleg Eyser
(Brookhaven National Laboratory)
6/1/18, 4:40 PM
PGDNN
Parallel
The Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory is the world's only polarized proton collider with center-of-mass energies up to 500 GeV and beam polarizations of about 60% at the highest energies. It provides unique opportunities to study the spin structure in hadronic systems and opens new kinematic regions compared to deep inelastic scattering experiments....
Dr
Bjoern Seitz
(University of Glasgow)
6/1/18, 5:10 PM
PGDNN
Parallel
Transverse momentum dependent distribution functions offer deep insights into the quark and gluon structure of the nucleon. Measuring asymmetries in Semi-Inclusive Deep Inelastic Scattering (SIDIS) of charged leptons off longitudinally and transversely polarised nucleons offers access to a variety of transverse momentum dependent distribution functions (TMD). The HERMES and COMPASS experiments...
Prof.
Marco Radici
(INFN - Sezione di Pavia)
6/1/18, 5:30 PM
PGDNN
Parallel
We present the first extraction of the transversity distribution in the framework of collinear factorization based on the global analysis of pion-pair production in deep-inelastic scattering off transversely polarized targets and in proton-proton collisions with one transversely polarized proton. The extraction relies on the knowledge of dihadron fragmentation functions, which are taken from...
Anselm Vossen
(Duke University/JLab)
6/1/18, 5:50 PM
PGDNN
Parallel
The first generation B-factories Belle and Babar, located at KEK and SLAC, respectively, took $e^+e^-$ annihilation data mostly near the $\Upsilon$(4S) resonance. Due to the size of the datasets, Belle sampled a record breaking 1 ab$^{-1}$, BaBar about half that, as well as the precision instrumentation and PID capabilities, these facilities have been an indispensable tool for the precision...
Dr
Emanuele Roberto Nocera
(Higgs Centre for Theoretical Physics)
6/1/18, 6:10 PM
PGDNN
Parallel
I review recent progress in the determination of the collinear fragmentation functions (FFs). I focus on the role of new data, improved theory and increased methodological sophistication in recent global QCD fits of light charged hadron FFs. I outline issues that are still open, and I discuss possible ways to assess the interplay between FFs and parton distribution functions (PDFs) in...
Dr
Maxime DEFURNE
(CEA-Saclay)
6/2/18, 4:10 PM
PGDNN
Parallel
The generalized parton distributions (GPDs) describe the correlations between the transverse position and the longitudinal momentum of a parton inside the nucleon. They represent the next step toward a complete description of the nucleon in terms of quarks and gluons. They are accessible through deep exclusive processes among which we find the deeply virtual Compton scattering (DVCS) and the...
Prof.
Matthias Grosse Perdekamp
(UIUC)
6/2/18, 4:40 PM
PGDNN
Parallel
The proton is a complex composite object. Its structure, the dynamics of its constituents and its mass presently cannot be calculated from Quantum Chromo Dynamics without simplifying model assumptions. Momentum- and spin-dependent distributions of the constituent partons, quarks and gluons, have been determined from the QCD analysis of data sets taken in deep inelastic lepton-proton scattering...
Dr
Adam Freese
(Argonne National Laboratory)
6/2/18, 5:10 PM
PGDNN
Parallel
Generalized parton distributions (GPDs) of the deuteron have been calculated. The results of these calculations and the formalism used will be presented. General properties of spin-1 GPDs, including polynomiality sum rules, will be discussed. It will be shown that these expected properties are observed in a convolution formalism if nuclear structure is calculated in a Lorentz-covariant manner....
Mrs
Fatiha Benmokhtar
(Duquesne University)
6/2/18, 5:40 PM
PGDNN
Parallel
It is well known that protons and neutrons are made from constituents, called quarks and gluons, which give substructure to these particles. The goal of this project is to make measurements of the spatial distributions and the momenta of the quarks that provide a three-dimensional map of quarks in the nuclear medium. This knowledge provides the basis of our understanding of nuclear matter in...
Anselm Vossen
(Duke University/JLab)
6/2/18, 6:10 PM
PGDNN
Parallel
Semi-inclusive deep inelastic Scattering (SIDIS) has been a very successful tool to investigate the partonic structure of the nucleon over the last decade. Compared to inclusive DIS, information about the quantum numbers of the struck quark can be inferred from the identity, distribution and polarization of the final state hadrons. Up to now, virtually all knowledge about the quark-gluon...
