POETIC6

Session

Spin-3D Parallel

8 Sept 2015, 16:10

Amphi Gay-Lussac (Ecole Polytechnique)

Conveners

Spin-3D Parallel

• Carlos Munoz Camacho

Spin-3D Parallel

• Daniel Boer (University of Groningen)

Spin-3D Parallel

• Michel Garçon

Description

Spin-3D Parallel session

18. Dual parametrization of GPDs v.s. the Mellin Barnes integral techniques

Kirill Semenov-Tian-Shansky (CPHT Ecole Polytechnique)

08/09/2015, 16:10

Spin and 3-d structure

Oral Presentation

The dual parametrization of generalized parton distributions (GPDs) and the Mellin-Barnes integral approach represent two frameworks for handling the double partial wave expansion of GPDs in the conformal partial waves and in the cross-channel SO(3) partial waves. We explicitly show the complete equivalence of these two independently developed GPD representations. This provides additional...

90. Internal structure of the nucleon (Proton / Neutron) by Virtual Compton Scattering at low and high energy

Meriem Benali (LPC Clermont Ferrand)

08/09/2015, 16:30

Spin and 3-d structure

Oral Presentation

We studied the internal structure of the nucleon with two complementary approaches: 1) At high-energy, the recently developed formalism of generalized parton distributions unifies the form factors and the parton distributions and provides access to new information. The simplest process sensitive to GPDs is the exclusive process "Deeply Virtual Compton Scattering (DVCS)". This work describes...

35. Probing transversity spin structure of a nucleon in neutrino-production of a charmed meson

Dr Lech Szymanowski (National Centre for Nuclear Reserarch)

08/09/2015, 16:50

Spin and 3-d structure

Oral Presentation

We study the scattering amplitude for exclusive neutrino production of a charmed meson on an unpolarized target. The analysis is performed within the colinear QCD approach, where generalized parton distributions (GPDs) factorize from perturbatively calculable coefficient functions. We demonstrate that the transversity chiral odd GPDs contribute to the transverse cross section if the hard...

7. Studies of the nucleon structure in back-to-back SIDIS

harut avakian

08/09/2015, 17:10

Spin and 3-d structure

Oral Presentation

The study of target fragmentation in Semi-Inclusive DIS is widely accepted as one of the main unique features of the Electron Ion Collider (EIC). Due to the lack of the analysis framework the current physics program of the EIC doesn’t cover observables involving hadrons produced in the target fragmentation region, which can shed light on the non-perturbative structure of the nucleon. In...

37. Radiative decays of resonances in lattice QCD

Mr Andria Agadjanov (University of Bonn)

08/09/2015, 17:30

Spin and 3-d structure

Oral Presentation

In lattice quantum chromodynamics the electroweak processes that contain resonances in the initial/final states are particularly interesting. Indeed the difficulty is here due to the fact that the resonances do not correspond to the isolated energy levels in the lattice simulations. The main goal is to establish analytically, using effective field theory methods, a connection between a finite...

94. Results on longitudinal spin physics at COMPASS

Malte Christian Wilfert (Johannes-Gutenberg-Universitaet Mainz (DE))

09/09/2015, 16:10

Spin and 3-d structure

Oral Presentation

The COMPASS experiment at the CERN SPS has taken data for deep inelastic scattering of polarised muons on a polarised NH$_3$ target in 2007 and 2011 and on a polarised LiD target in 2002-2004 and 2006. We will present our new results on the longitudinal double spin asymmetry $A_1^p$ and the spin-dependent structure function $g_1^p$ obtained from the 2011 data set. These results are used in a...

20. Probing Spin Dependent Quark and Gluon Distributions Through Azimuthal and Polarization Asymmetries

Prof. Gary Goldstein (Tufts University)

09/09/2015, 16:30

Spin and 3-d structure

Oral Presentation

Spin and transverse momentum dependent parton distributions - Generalized Parton Distributions, Transverse Momentum Distributions and related distributions - are at the interface between the QCD structure of the hadrons and observable quantities. The distributions are contained as linear superpositions within helicity amplitudes that factorize into universal forms at leading or next to leading...

15. GPDs in heavy mesons production and Compton scattering

Jakub Wagner (Institute for Nuclear Studies)

09/09/2015, 16:50

Spin and 3-d structure

Oral Presentation

Exclusive processes of heavy mesons production and spacelike and timelike deeply virtual Compton scattering allow us to investigate the hadron structure in terms of Generalized Parton Distributions (GPDs). We will review recent developments in the NLO description of such processes.

17. The unpolarized TMD fragmentation function at two loops

Ignazio Scimemi (Universidad Complutense (ES))

09/09/2015, 17:10

Spin and 3-d structure

Oral Presentation

I shall present the calculation of the unpolarized TMD fragmentation function at two loops. This result allows to evaluate the DIS results of future machines at the same perturbative precision as the Drell-Yan processes, namely NNLO. The calculation is also an explicit check of the factorization theorem for semi-inclusive DIS at two loops and of the universality of the evolution of the TMDs.

76. Using AdS / QCD models to get a Light - Front Wave Functions for Hadrons with arbitrary twist

Dr Alfredo Vega (Universidad de Valparaiso)

09/09/2015, 17:30

Spin and 3-d structure

Oral Presentation

Based on the matching of soft wall AdS / QCD models and Light - Front QCD for electromagnetic form factors, we derive a phenomenological wave function for hadrons with arbitrary twist dimension. Together with the Light Front Wave Function, we also obtain expressions for PDFs and GPDs.

31. Timelike Compton Scattering : calculation of observables and experimental perspectives at Jefferson Lab at 12 GeV

Marie BOER

11/09/2015, 09:00

Spin and 3-d structure

Oral Presentation

Hard exclusive processes such as photoproduction or electroproduction of photon or meson off the nucleon provide access to the Generalized Parton Distributions (GPDs), in the regime where the scattering amplitude is factorized into a hard and a soft part. GPDs contain the correlation between the longitudinal momentum fraction and the transverse spatial densities of quarks and gluons in the...

34. Revealing transversity GPDs through the production of a rho meson and a photon

Renaud Boussarie (LPT Orsay)

11/09/2015, 09:20

Spin and 3-d structure

Oral Presentation

Transversity GPDs have yet to be experimentally unraveled. We propose to probe them by studying the electro- or photo- production of a rho meson and a photon. At dominant twist, separating the longitudinal and transverse polarization of the meson allows one to get access to respectively usual (chiral even) and transversity (chiral odd) GPDs.

27. New results on deep exclusive pi0 and photon electroproduction in Jefferson Lab Hall A

maxime defurne

11/09/2015, 09:40

Spin and 3-d structure

Oral Presentation

We will show new results on exclusive pi0 and photon electroproduction in Jefferson Lab Hall A.

84. Single hadron double longitudinal spin asymmetries at $p_T \gt 1$ GeV/c and $Q^2 \lt 1$ GeV$^2$ measured at COMPASS and prospects for EIC

Maxime Levillain (CEA/IRFU,Centre d'etude de Saclay Gif-sur-Yvette (FR))

11/09/2015, 10:00

Spin and 3-d structure

Oral Presentation

In order to understand why quark spins only contribute about a third to the nucleon spin, quite a few recent experiments have focussed on the measurement of the gluon polarization in the nucleon. To access the gluon polarization reactions where the gluons from polarized nucleon significantly contributes are necessary. For example, choosing such a kinematic where the Photon Gluon Fusion (PGF)...

61. Non-dipolar Wilson links for transverse-momentum-dependent wave functions

Dr Yu-Ming Wang (TU Munich)

11/09/2015, 10:20

Spin and 3-d structure

Oral Presentation

We propose a new definition of a transverse-momentum-dependent (TMD) wave function with simpler soft subtraction for $k_T$ factorization of hard exclusive processes. The un-subtracted wave function involves two pieces of non-light-like Wilson links oriented in different directions, so that the rapidity singularity appearing in usual $k_T$ factorization is regularized, and the pinched...