POETIC6

7 Sept 2015, 08:00 → 11 Sept 2015, 18:40 Europe/Zurich

Amphi Gay-Lussac (Ecole Polytechnique)

Bernard Pire, Cyrille Marquet (CPHT - Ecole Polytechnique), Franck Sabatié (CEA Saclay)

POETIC6, the 6th edition of the International Conference on the "Physics Opportunities at an ElecTron-Ion Collider", will take place at Ecole Polytechnique in Palaiseau, France from Monday, September 7th to Friday, September 11th 2015, a few weeks before the National Science Advisory Committee recommends a new Long Range Plan to the United States' DOE and NSF. 

In the midst of this much-anticipated report, and following earlier workshops at Stellenbosch, Bloomington, Valparaiso, Jyvaskyla and Yale, it is timely for the POETIC series to become an international conference. The primary goal will remain to continue the advancement of the field of electron-ion collider physics. 

While the central theme of the conference will be the physics of a future electron-ion collider, the conference will also cover strongly-related physics in the CEBAF, RHIC, and LHC experimental programs. The conference will aim primarily at developments on the theory/phenomenology side, but the latest accelerator and experimental developments of interest will also be reviewed. It will foster exchanges between theory, phenomenology and experiment. 

The conference will be held within the Ecole Polytechnique, close to Paris and with convenient public transportation to its center. In addition to the plenary sessions, parallel sessions will also be organized if deemed necessary. Young physicists, post-docs and students, are especially encouraged to attend, some financial support will be available for them. 

In order to submit an abstract, you either need to use a previous CERN indico account or if you do not have one, to create a CERN Lightweight account at the following address: https://account.cern.ch/account/Externals/RegisterAccount.aspx

Monday, 7 September

Registration

Welcome

Welcome

1 Welcome

Welcome speech and practical information about the conference.

Speakers: Cyrille Marquet (CPHT - Ecole Polytechnique), Franck Sabatié (CEA Saclay)

opening.pptx

Keynote

Keynote

2 The US-based Electron-Ion Collider: Imaging the Gluons and Quark Sea of Nucleons and Nuclei

The interior landscape of nucleons includes a strong-force driven sea of quarks, antiquarks and gluons, with a net surplus of a few ever-present valence quarks. In order to understand how the properties and structure of all forms of nuclear matter emerge from the dynamics of QCD, it is essential to precisely image the gluons and quarks, and to understand the role they and their interactions play in nucleons and nuclei. For this, a new accelerator facility is required, the Electron-Ion Collider, to match the valence quark studies of the upgraded Jefferson Lab. Such a future facility would be the world's first polarized electron-proton collider, and the world's first e-A collider. The science foreseen at and the status of such a future US-based polarized Electron-Ion Collider will be presented.

Speaker: Rolf Ent (Jefferson Lab)

POETIC6_EIC_US_ent.pdf

POETIC6_EIC_US_ent.pptx

10:20 Coffee Break

Coffee Break

Future facilities

Future facilities session

Convener: Franck Sabatié (CEA Saclay)

3 Overview of the LHeC Project

The LHeC project aims to supplement the LHC with a new electron accelerator in order to facilitate electron-proton and electron-ion collisions at unprecedented luminosities and centre-of-mass energies. This talk will include an update on the accelerator and detector aspects of the project. It will also survey the main physics topics of interest, including Higgs boson production and parton density constraints as well as a wide range of issues in low x physics.

Speaker: Paul Richard Newman (University of Birmingham (GB))

POETIC-newman.pdf

4 Design of High-energy High-luminosity electron-ion collider eRHIC

In this talk I will present most recent design of electron-ion collider at Brookhaven National Laboratory, eRHIC. In eRHIC we would collide polarized electrons (energy from 5 to 21.2 GeV) with polarized protons (energy from 100 GeV to 250 GeV), polarized He3-ion and heavy ions (energy from 50 to 100 GeV/u). Based on linac-ring design, eRHIC will cover the full range of c.m. energies covered in EIC white paper (arXiv:1212.1701) and described in the EIC physics case ( arXiv:1212.1701) with luminosity reaching 2E34 1/sec/cm^2. I will also present the R&D program towards eRHIC pursued at BNL and Stony Brook University.

Speaker: Vladimir Litvinenko (Stony Brook University)

eRHIC talk at POETIC 2015.pdf

eRHIC talk at POETIC 2015.pptx

5 The JLab/MEIC Detector Design and Integration with the Accelerator Lattice

The MEIC design includes two Interaction Points (IPs), each of which can operate simultaneously at full luminosity. Each IP is located near the downstream ends of the ion arc and of the electron straight section. This minimizes backgrounds from both synchrotron radiation and ion beam-gas interactions. The detector and beam-line optics for IP1 are designed to be nearly hermetic for all particles outside the presumed 10-sigma admittance of the figure-8 accelerator lattice. The IP2 layout is designed to be consistent with the EIC detector concept based on the BaBar solenoid. The integration of the IP1 detector with the lattice extends ~40 m downstream of the IP in both the electron and ion directions. The central region of the detector is a new 4 m long 3 m diameter 3 Tesla solenoid. However, the detector design is geometrically compatible with the CLEO solenoid (1.5 T) that will soon be delivered to JLab for the SoLID project. Particle ID is provided by TOF, DIRC, and EM calorimetry in the barrel region, Cerenkov, RICH, and EM calorimetry in the electron End-Cap, and RICH, TOF, and EM calorimetry in the ion End-Cap (with an option to include hadronic calorimetry). Analysis in the forward ion directions is enhanced by the 50 mrad crossing angle at the IP, and a two-stage spectrometer integrated into the first 36 m of the accelerator lattice. On the electron downstream side, after the electron Final Focus Quad triplet , there is a four dipole chicane which provides the optics for both tagging of quasi real photo-production at the IP and a Compton polarimeter.

Speaker: Charles Hyde (Old Dominion University)

POETIC2015_MEIC_Detector_CEH.pdf

POETIC2015_MEIC_Detector_CEH.pdf

POETIC2015_MEIC_Detector_CEH.pptx

6 The design of the MEIC Accelerator at Jefferson Lab

I will discuss the overall design of the MEIC accelerator complex at Jefferson Lab with particular focus on the design optimization achieved over the past 12-15 months. The baseline is mature, a first pass cost estimate has been completed and the overall technical risk has been minimized. I will then outline the plan for the necessary accelerator R&D, preliminary results and future challenges.

Speaker: Fulvia Pilat (Department of Physics)

Pilat - MEIC Design at JLAB.pdf

Pilat - MEIC Design at JLAB.pptx

12:20 Lunch Break

Lunch Break

Small-x

Small-x session

Convener: Dr Samuel Wallon

7 Small-x Physics at the LHeC

The Large Hadron-Electron Collider LHeC is a proposed upgrade of the LHC to study ep/eA collisions in the TeV regime, by adding a 60 GeV electron beam through an Energy Recovery Linac. In this talk we will review the possibilities for studying the small-x region in this machine, with emphasis in the potential for unravelling the existence of a novel, non-linear saturation regime of QCD through inclusive and exclusive observables in ep and eA collisions.

Speaker: Nestor Armesto Perez (Universidade de Santiago de Compostela (ES))

armesto_POETIC6_1509_smallx.pdf

8 JIMWLK: From concepts to observables

Speaker: Heribert Weigert (University of Oulu)

2_Wiegert_POETIC-2015.pdf

9 Resumming large radiative corrections in the high-energy evolution of the Color Glass Condensate

The BK-JIMWLK equations describing the evolution of the Color Glass Condensate with increasing energy have recently been extended to next-to-leading order (NLO) accuracy. However, some of the NLO corrections turn out to be extremely large, since amplified by (double and single) `collinear’ logarithms, i.e. logarithms of ratios of transverse momenta. This difficulty points towards the existence of large radiative corrections to all orders in $\alpha_s$,as generated by the transverse phase-space, which must be computed and resummed in order to restore the convergence of the perturbative expansion. In a couple of recent papers, we developed a resummation scheme in that sense, which achieves a complete resummation of the double-logarithmic corrections and a partial resummation of the single-logarithmic ones (including the running coupling effects). We have thus deduced a collinearly-improved version of the BK equation which includes the largest radiative corrections to all orders. To demonstrate the usefulness of this equation as a tool for phenomenology, for have used it for fits to the HERA data for electron-proton deep inelastic scattering at high energy. We have obtained excellent fits with a reduced number of free parameters and with initial conditions at low energy taken from perturbative QCD.

Speaker: Edmond Iancu (CEA/IRFU,Centre d'etude de Saclay Gif-sur-Yvette (FR))

Iancu_POETIC2015.pdf

10 Collinearly improved BK equations versus HERA data

In this talk I shall discuss the ability of the collinearly improved BK equations recently proposed in the literature by G. Beuf (1401.0313) and Iancu et al. (arXiv:1502.05642) to describe data on the reduced cross section in e+p collisions at small values of Bjorxen-x measured at HERA by the H1 and ZEUS collaborations. I shall present a comparative study of the result of global fits to these data based on the running coupling BK equation with and without double logarithmic corrections encoded in those equations.

Speaker: Javier L Albacete (Universidad de Granada)

POETIC2015_Albacete.pdf

POETIC2015_Albacete_small.pdf

11 Single inclusive particle production at NLO: improved CGC treatment.

We discuss the recent improvement of the NLO calculation of single inclusive particle production in pA collisions within the CGC formalizm. The two points that have not been addressed previously, and are treated consistently in the current approach are the Ioffe time cutoff on the configurations that can participate in the scattering, and the careful treatment of the evolution interval.

Speaker: Alex Kovner (University of Connecticut)

POETICVI.pdf

16:15 Coffee Break

Coffee Break

Spin-3D

Spin-3D session

Convener: Bernard Pire

12 What do we know and expect from TMDs?

The Transverse Momentum Dependent Partonic Distributions (TMD-PDFs) and Fragmentation Functions (TMD-FFs) should reveal new properties of the 3-dimensional structure of nucleons and of the hadronization process. Many experimental data are now available and much progress has been made in their phenomenological interpretation. A short summary of the situation is presented.

Speaker: Mauro Anselmino (Torino University and INFN)

Anselmino.pdf

13 Phenomenological status of Generalized Parton Distributions

Only a consistent QCD framework for a unique description of Compton scattering and meson production in the deeply virtual regime allows to address generalized parton distributions in a universal manner. Such a framework allows also to bridge experimental measurements and results from lattice simulations on a quantitative level and it can be utilized to address the partonic decomposition of the nucleon spin and the three dimensional distribution of partons. In this talk the status of describing experimental data is reviewed, where the need of precision measurements is stressed, and an outlook of possible theoretical developments is given.

Speaker: Dr Dieter Mueller (University of Cape Town)

DieterMueller-Poetic-15.pdf

14 Towards high accuracy in QCD predictions in DVCS

I discuss recent theoretical progress in making QCD description of DVCS fully quantitative, including target mass and finite-t corrections and the calculation of the scale-dependence of generalized parton distributions to the NNLO accuracy.

Speaker: Vladimir Braun (University of Regensburg)

poetic.pdf

15 Status of DVCS fits after 2015 JLab data

It will be shown how the new data on DVCS cross-section and asymmetries coming from CLAS and Hall A JLab collaborations influence global fits.

Speaker: Kresimir Kumericki (University of Zagreb)

kumericki-poetic6.pdf

16 Fit of Compton Form Factors

Generalized Parton Distributions (GPDs) allow to describe the structure of the nucleon in a very rich and unprecedented way: they contain the correlations between the (transverse) position and (longitudinal) momentum distributions of the partons in the nucleon, they allow to derive the orbital momentum contribution of partons to the nucleon's spin, they provide an access to the nucleon's ($q\bar{q}$) content, etc... GPDs can be accessed experimentally through the exclusive leptoproduction of a photon (``Deep Virtual Compton Scattering", DVCS). In this presentation, we will present the latest results of our fitter code which aims at extracting, in a largely model-independent way, the GPD information, namely Compton form Factors, from experimental data. We will show the results of this code applied to the latest JLab and HERMES DVCS data, which begin to provide some new insights on nucleon structure.

Speaker: Michel GUIDAL (CNRS)

poetic6_guidal.pdf

poetic6_guidal.pptx

19:00 Reception

Reception

Tuesday, 8 September

pp-pA-AA

pp-pA-AA session

Convener: Raphael Dupre (IPN Orsay)

17 The initial stages of heavy ion collisions

In this talk, I will discuss heavy ion collisions from the point of view of the Color Glass Condensate framework, in which the colliding nuclei are described as collections of light-cone color sources. Part of my presentation will be devoted on factorization and the universal aspects of the CGC that are common to eA, pA and AA collisions. Then, I will turn to the more AA-specific question of the evolution of the system very shortly after the collision.

Speaker: Francois Gelis

Gelis-POETIC6.pdf

18 Forward di-jet production in dilute-dense collisions

We propose a factorization formula for the cross section for forward di-jet production in dilute-dense collisions. The new formula is applicable for an arbitrary value of the momentum imbalance of the two jets, $k_t$. This generalizes the transverse momentum dependent (TMD) factorization formula that has been derived before by Dominguez et al. Their formula is valid only for small values of the transverse momentum of the small-x gluon from the target; it has $k_t$ dependent TMD gluon distributions, but on-shell hard matrix elements. We extend their formula to all ranges of $k_t$ by including off-shell matrix elements. We also add finite $N_c$ corrections. The derivation is done with a standard Feynman diagram technique, and, independently, with a color ordered amplitudes method. The new formula encompasses both, the TMD factorization for small $k_t$ on the order of the saturation scale, and the High Energy Factorization (HEF) for large $k_t$ on the order of the momentum of the jets. The TMD and HEF factorizations can be derived from the Color Glass Condensate (CGC) formula for forward di-jet production in the appropriate limits. We show explicitly the equivalence of HEF and CGC in the dilute target approximation.

Speaker: Elena Petreska (Ecole Polytechnique)

petreska.pdf

19 Forward dijet production and improved TMD factorization in dilute-dense hadronic collisions

We study inclusive dijet production at small x in hadronic collisions. We show that the commonly used High Energy Factorization approach can be motivated in this context in a specific window where the transverse momentum imbalance of the dijet system is much smaller than the transverse momenta of the individual jets, but still much larger than the saturation scale. Then we extend the framework outside this kinematic window to the case of arbitrarily small transverse momentum imbalance. That involves generalizing the Transverse Momentum Dependent (TMD) factorization formula for dijet production to the case of finite Nc and with one of the incoming gluons being off-shell. We discuss the features of this new improved TMD factorization and relate it to the colour-ordered amplitude formalism.

Speaker: Sebastian Piotr Sapeta (CERN)

sapeta-poetic15.pdf

20 Nuclear suppression in p-A collisions from induced gluon radiation

In high-energy p-A collisions, hadron production at large enough rapidity and moderate pt is suppressed compared to p-p collisions. An important effect contributing to such a nuclear suppression is the medium-induced, coherent gluon radiation associated to the underlying partonic process. I will review the main features of induced coherent radiation, and show the predictions for quarkonium and light hadron nuclear suppression of a simple phenomenological model based on this effect.

Speaker: Stephane Peigne

peigne.pdf

Conference Photo

10:50 Coffee Break

Coffee Break

Spin-3D

Spin-3D session

Convener: Lech Szymanowski

21 Lattice QCD calculations of transverse momentum-dependent parton distributions (TMDs)

An ongoing program of evaluating TMD observables within lattice QCD is reviewed, summarizing recent progress with respect to several challenges faced by such calculations. These lattice calculations are based on a definition of TMDs through hadronic matrix elements of quark bilocal operators containing staple-shaped gauge connections. A parametrization of the matrix elements in terms of invariant amplitudes serves to cast them in the Lorentz frame preferred for a lattice calculation. Results presented include data on the naively T-odd Sivers and Boer-Mulders effects.

Speaker: Michael Engelhardt (New Mexico State University)

engelhardt.pdf

22 Dispersion representation of the D-term form factor deeply virtual Compton scattering

We review the dispersion analysis of deeply virtual Compton scattering and present a dispersive representation of the D-term form factor for hard exclusive reactions. We use unsubtracted $t$-channel dispersion relations, where the $t$-channel unitarity relation is saturated with the contribution of two-pion intermediate states, using the two-pion distributions amplitude for the $\gamma^*\gamma\rightarrow \pi\pi$ subprocess and reconstructing the $\pi\pi\rightarrow N\bar N$ subprocess from available information on pion-nucleon partial-wave helicity amplitudes. Results for the D-term form factor as function of $t$ as well as at $t=0$ are discussed in comparison with available model predictions and phenomenological parametrizations.

Speaker: Barbara Pasquini (University of Pavia)

Pasquini-POETIC2015-final.key

Pasquini-POETIC2015-final.pdf

23 Towards a Direct Measurement of the Quark Orbital Angular Momentum Distribution

We discuss the canonical (Ji) and kinetic/mechanical (Jaffe and Manohar) definitions of partonic orbital angular momentum (OAM). It was recently shown by Hatta and Burkardt that the two definitions correspond to the second moment in intrinsic k_T of the same generalized transverse momentum distribution (GTMD), while they differ in their gauge link structure. At the same time, as first observed by Polyakov, canonical orbital angular momentum can be independently described in terms of a twist three generalized parton distribution, which only a straight type of gauge link is allowed for. Here we provide further insight into this problem by showing that the second moment in k_T of the OAM twist two GTMD and twist three GPD, are connected through a Wandzura Wilzceck type relation which generalizes the one originally developed for the polarized twist three distribution, g_T [1]. An important outcome of the picture we provide is that the two different mechanisms for generating partonic OAM can be both tested experimentally and validated by lattice calculations. Additional model calculationsare shown that provide an initial guidance for assessing the size of the various contributions. [1] S. Liuti, talk delivered at CIPANP 2015 http://indico.wlab.yale.edu/indico/event/2/session/6/contribution/178

Speaker: Prof. simonetta liuti (university of virginia)

sl_Poetic15.pdf

sl_Poetic15.pptx

12:25 Lunch Break

Lunch Break

Small-x

Small-x session

Convener: Edmond Iancu (CEA/IRFU,Centre d'etude de Saclay Gif-sur-Yvette (FR))

24 Gluon TMD studies at EIC

Transverse momentum dependent parton distributions (TMDs) are currently under active investigation, both theoretically and experimentally. For studies of the gluon TMDs higher energy or smaller x values are required. EIC can offer ideal probes for studies of the distributions of unpolarized and linearly polarized gluons inside unpolarized protons, and of the gluon Sivers effect for transversely polarized protons. These distributions and what we can learn about them at EIC will be reviewed in this talk, with emphasis on the promising observables, the process dependence and the expected small-x behavior of the distributions.

Speaker: Daniel Boer (University of Groningen)

POETICVI-Sept-2015-4.pdf

25 TMDs in the Saturation Picture: Quasi-Classical Approximation and Quantum Evolution

We set up a formalism for calculating transverse-momentum-dependent parton distribution functions (TMDs) using the tools of saturation physics: quasi-classical approximation and quantum evolution. In the quasi-classical approximation we show how to calculate the quark TMDs of a nucleus at large-x: the unpolarized quark distribution, the Sivers function, and the quark Boer-Mulders distribution. We observe that spin-orbit coupling leads to mixing between different TMDs of the nucleus and of the nucleons. We then consider the evolution of TMDs: at large-x, in the double-logarithmic approximation, we obtain the Sudakov form factor. At small-x the evolution of unpolarized-target quark TMDs is governed by BK/JIMWLK evolution, while the small-x evolution of polarized-target quark TMDs appears to be different, involving the QCD Reggeon mixing with non-BFKL gluon ladders. The small-x evolution of the quark helicity TMD appears to give a steep rise of the TMD with decreasing x thus suggesting that there is a lot of spin at small-x. This conclusion may lead to the eventual resolution of the spin puzzle.

Speaker: Prof. Yuri Kovchegov

POETIC15.pdf

POETIC15.pptx

26 Rapidity evolution of gluon TMD from low to moderate x

I discuss how the rapidity evolution of gluon transverse momentum dependent distribution changes from nonlinear evolution at small x<<1 to linear evolution at moderate x~1.

Speaker: Ian Balitsky (ODU/JLab)

gTMD_20min.pdf

27 Polarized Gluon TMDs at small x

Polarized gluon TMDs are not necessarily suppressed at small x. One of the notable example is the linearly polarized gluon distribution which actually saturates the positivity bound in the dilute region. In this talk, I will discuss three leading power T-odd gluon TMDs inside a transversely polarized target. It is shown that all of three gluon TMDs receive leading logarithm ln(1/x) contribution and thus are not suppressed at small x. We further find that they can be related to the spin dependent odderon and become identical at small x.

Speaker: Dr jian zhou (Nikhef)

small x polarized gluon TMDs.pdf

small x polarized gluon TMDs.pdf

28 High-energy resummation effects in Mueller-Navelet jets production at the LHC

We study the production of two forward jets with a large interval of rapidity at hadron colliders, which was proposed by Mueller and Navelet as a possible test of the high energy dynamics of QCD, within a complete next-to-leading logarithm framework. We show that using the Brodsky-Lepage-Mackenzie procedure to fix the renormalization scale leads to a very good description of the recent CMS data at the LHC for the azimuthal correlations of the jets. We argue, based on the comparison of the lowest order non trivial corrections $\mathcal{O}(\alpha_s^3)$ to the cross section with predictions of an exact calculation, that the inclusion of next-to-leading order corrections to the jet vertex significantly reduces the importance of energy-momentum non-conservation which is inherent to the BFKL approach.

Speaker: Dr Samuel Wallon

Wallon-POETIC-VI.pdf

15:50 Coffee Break

Coffee Break

Small-x Parallel

Small-x Parallel session

Convener: Francois Gelis

29 CGC beyond eikonal accuracy

We present a new method to systematically calculate corrections to the eikonal approximation in the background field formalism. We calculate the subleading power-suppressed corrections due to the finite width of the target to first and second orders. The method is of generic applicability. As a first example, we study both polarized and unpolarized gluon production in pA collisions.

Speaker: Tolga Altinoluk

Altinoluk_POETIC.pdf

30 Quarkonium photoproduction in pp and AA at the LHC

Speaker: Maria Beatriz De Leone Gay (U)

gay-ducati.pdf

31 NLO evolution of 4-point colorless operators

This talk discusses the derivation of the NLO evolution equations for the quadrupole and the double dipole operators. It contains the evolution equations for both the standard and the conformal composite operators.

Speaker: Andrey Grabovskiy (Budker Institute of Nuclear Physics (RU))

Poetic6grabovsky.pdf

32 Classical Gluon Production Amplitude in Heavy Ion Collisions

The distribution of quarks and gluons produced in the initial stages of nuclear collisions, known as the initial condition for the Quark-Gluon Plasma formation, is the fundamental building block of heavy ion theory. I will present the scattering amplitude, beyond the leading order, of the classical gluon produced in heavy ion collisions. The result is obtained in the framework of saturation physics and Wilson lines formalism.

Speaker: Giovanni Antonio Chirilli (The Ohio State University)

Poetic6-7-11-Sep-2015-Paris.pdf

33 Searching saturation effecs in inclusive and exclusive eA processes

The searching of saturation effects in inclusive and exclusive $eA$ collisions is reviewed. In particular, we present a comparison between the linear and nonlinear predictions for the nuclear structure functions as well as for the vector meson production in future $eA$ colliders. Finally, we present our recent results for the nuclear Deep Virtual Compton Scattering.

Speaker: Victor Gonçalves (Universidade Federal de Pelotas)

Victor_POETIC.pptx

Spin-3D Parallel

Spin-3D Parallel session

Convener: Carlos Munoz Camacho

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

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 insight into the GPD properties and their physical interpretation. We discuss the relation between the J=0 fixed pole contribution into the Compton scattering amplitude and the D-term form factor. We argue that in the Bjorken limit the J=0 fixed pole universality hypothesis of S. Brodsky, F. Llanes-Estrada and A. Szczepaniak is equivalent to the conjecture that the D-term form factor is given by the inverse moment sum rule. We also briefly discuss applications for GPD modeling and map the phenomenologically successful Kumericki-Mueller GPD model to the dual parametrization framework.

Speaker: Kirill Semenov-Tian-Shansky (CPHT Ecole Polytechnique)

Talk_Paris_Semenov_08.09.pdf

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

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 the measurement of the cross section of the DVCS reaction off the neutron using a Deuterium target. Theoretical models predict that the DVCS on the neutron is mostly sensitive to the GPD "E" which allows to access the orbital angular momentum of the quarks via Ji's sum rule. The analyzed data were taken in the Hall A of Jefferson Lab, with a polarized electron beam at Q2=1.75GeV2 and xB=0.36. We extracted, for the first time, a non-zero contribution of {neutron-DVCS + coherent-deuteron-DVCS}. 2) At low-energy, the internal structure of the nucleon is inaccessible in terms of its elementary constituents. The extracted observables refer to more global properties of hadrons. Under the pion production threshold, the Virtual Compton Scattering (VCS) is parametrized by new observables : the generalized electric and magnetic polarisabilities (GPs), α(Q2) and β(Q2) . These observables describe the induced local deformation in the nucleon under an external electromagnetic field. These Gps are measured at Q2=0.5GeV2 with an experiment conducted at the accelerator of Mainz in Germany. Two methods, based on the dispersion relations (DR) and a low-energy approach (LEX), were used to extract two linear combinations of GPs : (P_{LL}-(P_{TT}/ε)) and P_{LT}. Preliminary results show a good agreement between both methods and a measurement of α(Q2) and β(Q2) is obtained with the DR model.

Speaker: Meriem Benali (LPC Clermont Ferrand)

benali.pdf

benali.pptx

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

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 amplitude is calculated up to order m_c/Q. We show how to access these GPDs through analysis of the azimuthal dependence of the neutrino N —> mu^- D^+ N differential cross section.

Speaker: Dr Lech Szymanowski (National Centre for Nuclear Reserarch)

SzymanowskiPOETIC15.pdf

37 Studies of the nucleon structure in back-to-back SIDIS

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 recent pioneering studies involving the target fragmentation by Anselmino and Co. it has been shown that new beam–spin asymmetry appears in deep inelastic inclusive lepto-production at low transverse momenta when a hadron in the target fragmentation region is observed in association with another hadron in the current fragmentation region. First preliminary measurements of that asymmetry are already available from JLab. The EIC provide much wider kinematical coverage and better separation of current fragmentation and target fragmentation regions, and due to high polarization of electrons and protons is a natural choice for measurements of different spin dependent observables in back-to-back or b2b SIDIS. In this talk, we present a program for extending the studies of the nucleon structure beyond the traditional current fragmentation, when a hadron in the target fragmentation region is observed in association with another hadron in the current fragmentation region.

Speaker: harut avakian

avakian-poetic-2015.pdf

avakian-poetic-2015.ppt

38 Radiative decays of resonances in lattice QCD

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 volume lattice data and (infinite volume) scattering observables. This will allow to perform an ab initio lattice extraction of the physical quantities, such as the decay rates and form factors. Phenomenologically interesting processes include the $\Delta N\gamma^*$ transition [1] which was studied following this line in [2] and the rare decays $B\rightarrow K^*\gamma^*$ [3]. [1] C. Alexandrou et al., Phys. Rev. B **83** (2011) 014501. [2] A. Agadjanov et al., Nucl. Phys. B **886** (2014) 1199. [3] R. Horgan et al., Phys. Rev. D **89** (2014) 094501.

Speaker: Mr Andria Agadjanov (University of Bonn)

presentation_france.pdf

Wednesday, 9 September

BSM

BSM session

Convener: Ingo Schienbein (Universite Joseph Fourier)

39 Electroweak and Beyond the Standard Model Physics at the EIC

The EIC will reach new frontiers in accessible center-of-mass energies and polarized luminosity. These characteristics, coupled with the event topologies in collider mode, will allow exceptionally clean and precise measurements of neutral current amplitudes over a wide range of Q2 for the first time. In this talk, we discuss the new observables that would become accessible and the resulting physics such as measurements of novel neutral current structure functions, precision measurements of the electroweak mixing angle at intermediate Q2 values, and unique searches for lepton flavor violation.

Speaker: Prof. Krishna Kumar (Stony Brook University)

kumar_poetic6_bsmeic.pdf

40 Precision measurement of the weak mixing angle at MESA

MESA, the Mainz Energy-Recovering Superconducting Accelerator, will offer the possibility to measure the scattering of polarized electrons off protons at small energies (E=155 MeV) with very high precision.The parity-violating polarization asymmetry is determined by the weak charge of the proton and offers the possibility to measure the weak mixing angle with a relative precision of 0.13 %, competitive with past high-energy and upcoming LHC measurements. I will discuss challenges and the status of calculations of theoretical predictions for this measurement.

Speaker: Hubert Spiesberger (Mainz University)

spiesber-poetic15.pdf

41 The neutrino-nucleon cross section at UHE and its astrophysical implications

We present a quantitative study of the νN cross section in the neutrino energy range 10^4< E_ν < 10^14 GeV within two transversal QCD approaches: NLO DGLAP evolution using different sets of PDFs and BK small-x evolution with running coupling and kinematical corrections. We show that the non-linear effects embodied in the BK equation yield a slower raise in the cross section for E_ν>10^8 GeV than the usual DGLAP based calculation. Finally, we translate this theoretical uncertainty into upper bounds for the ultra-high-energy neutrino flux for different experiments.

Speaker: Ms Alba Soto Ontoso (Universidad de Granada)

talkParisAlba.pdf

42 Proton radius puzzle: the status

Recent measurements of the Lamb shift in muonic hydrogen led to an extracted value of the proton charge radius $R^p_{\mu H}=0.84087(39)$ deviating from that obtained with a combined electronic hydrogen spectrum and electron scattering $R^p_{eH,\,e-scatt.}=0.8775(51)$ by 7 standard deviations. This discrepancy was coined "the proton radius puzzle" and has attracted much interest both on the theory and experiment side. I review the current status of the field that comprises experiments with light muonic atoms, hydrogen spectroscopy and scattering with electrons and muons, as well as the theory of the standard model and beyond.

Speaker: Misha Gorshteyn (KPH Universtät Mainz)

Poetic Sep9 2015.key.zip

Poetic Sep9 2015.pdf

10:40 Coffee Break

Coffee Break

PDFs

PDFs session

Convener: Gregory Soyez (CEA/IRFU,Centre d'etude de Saclay Gif-sur-Yvette (FR))

43 Frontiers of QCD with Precision nPDFs

nPDF global analyses typically impose strong kinematic cuts on the data sets to avoid theoretically complicated regions. High-statistics measurements from an EIC could provide the precision to explore these extreme limits of QCD including hi-x, low-Q, small-x, intrinsic flavor, & nuclear matter effects. New EIC measurements would yield improved precision for nPDFs, thereby driving theoretical investigations, which would ultimately provide a deeper understanding of the underlying QCD theory. The nPDFs play a pivotal role in this study, and we examine some of the limitations as well as recent progress.

Speaker: Fred Olness (Southern Methodist University)

OLNESS_POETIC6_Final.pdf

44 Progress on nuclear modifications of structure functions

I report our recent studies on nuclear structure functions. First, nuclear parton distribution functions are determined by analyzing high-energy nuclear reaction data. Using charged-lepton and neutrino scattering data, we investigate whether there are significant differences between nuclear modifications in the charged-lepton and neutrino reactions. This issue was first pointed out by the nCTEQ collaboration. Second, nuclear effects on the polarized structure function $b_1$ are investigated in the deuteron. It is important to show theoretical estimates at this stage because an experimental proposal was approved at JLab to measure $b_1$. The studies could open a new field of spin physics for spin-one hadrons.

Speaker: Prof. Shunzo Kumano (KEK)

sk-nucl-poetic-2015-09.pdf

sk-nucl-poetic-2015-09.ppt

45 nCTEQ15 nuclear parton distributions with uncertainties

We present the first official release of the nCTEQ nuclear parton distribution functions with errors. The main addition to the previous nCTEQ PDFs is the introduction of PDF uncertainties based on the Hessian method. Another important addition is the inclusion of pion production data from RHIC giving us a handle to constrain gluon PDF. In this presentation we briefly discuss the framework of our analysis and concentrate on the comparison of our results with those of other groups providing nuclear parton distributions.

Speaker: Aleksander Kusina (LPSC Grenoble)

kusina_Poetic2015.pdf

12:15 Lunch Break

Lunch Break

Spin-3D

Spin-3D session

Convener: Abhay Deshpande (Stony Brook University)

46 The 3D structure of QCD

For many phenomenological applications involving hadrons in high energy processes the hadronic structure can be taken care of by parton distribution functions (PDFs), in which only the collinear momenta of quarks and gluons are important. In principle the transverse structure, however, provides interesting new phenomenology. Taking into account transverse momenta of partons one works with transverse momentum dependent PDFs (TMDs), which go beyond spin-spin correlations, allowing also spin-orbit correlations, which have a time reversal odd character and lead to new observables. The embedding of the transverse structure in the field theoretical framework of QCD, needed among others for the study of universality and for investigating the evolution of TMDs, is quite cumbersome. Besides looking at some recent developments of the universality aspects, I also will speculate on a novel view of the 3-dimensional structure of QCD, which fits in a broader study looking at the roots of the Standard Model of particle physics.

Speaker: Piet Mulders (VU/Nikhef)

Mulders_2015-POETIC6.pdf

Mulders_2015-POETIC6.pptx

47 Measurements of transverse spin and transverse momentum effects at COMPASS

The CERN COMPASS experiment has a broad physics program focused on the nucleon spin structure and on hadron spectroscopy, using muon and hadron beams. One of the main objectives for the spin program with the muon beam is the measurement of transversity and of transverse spin and momentum effects in semi inclusive deep inelastic scattering. After o short description of the experiment, an overview of the recent results covering this topic will be given, together with a perspective for the near future.

Speaker: Andrea Bressan (Universita e INFN, Trieste (IT))

bressan_poetic2015.pdf

bressan_poetic2015.pptx

bressan_poetic2015v2.pdf

bressan_poetic2015v2.pptx

48 New contributions to gluon poles in semi-inclusive processes

We consider the direct photon production in two hadron collision with one transversely polarized hadron. We find new twist $3$ contributions to the hadron tensor associated with this process. We demonstrate that these new terms, first, play a crucial role to prove both the QED and QCD gauge invariance and, second, give the sizeable contribution to the hadron tensor compared to the standard terms. Based on the use of the contour gauge conception, we present the evidences for the existence of new terms in the hadron tensor. We discuss the effects which lead to the universality breaking for the corresponding twist 3 parton distributions.

Speaker: Dr Igor Anikin (JINR)

Anikin-Talk-POETIC15-v2.pdf

49 Wide Angle Compton Scattering within the SCET factorization framework

Existing data for the electromagnetic proton form factors and for the cross section of the wide angle Compton scattering (WACS) shows that the hard two-gluon exchange mechanism (collinear factorization) is still not applicable in the kinematical region where Mandelstam variables $s \sim -t \sim -u$ are about few GeV$^2$. On the other hand these observables can be described in phenomenological models where spectator quarks are soft which assumes a large contribution due to the soft-overlap mechanism. It turns out that the simple QCD factorization picture is not complete and must also include the soft-overlap contribution which can be described as a certain matrix element in the soft collinear effective theory (SCET). Then the leading power contribution to WACS amplitude is described as a sum of the hard- and soft-spectator contributions. The existing experimental data allows one to check certain conclusions based on the assumption about dominant role of the soft-spectator mechanism.

Speaker: Nikolay Kivel (Helmholtz Institute Mainz)

NKivel POETIC2015.pdf

50 Spin-Directed Momentum Transfers in the SIDIS Target Fragmentation Region

Transverse single-spin asymmetries are an important tool in the study of hadronic structure. These asymmetries can be parameterized in terms spin-directed momentum transfers generated by nonperturbative spin-orbit mechanisms in QCD. The target fragmentation region in SIDIS processes provides access to asymmetries such as final-state polarization asymmetries in addition to target spin asymmetries. The presentation demonstrates how the TMD formalism applied to fracture functions provides significant information that can be constructively used to understand independent aspects of baryon structure.

Speaker: Dennis Sivers (Portland Physics Institute)

Paris slides.pdf

15:50 Coffee Break

Coffee Break

PDFs Parallel

PDFs Parallel session

Convener: Cédric Lorcé (University of Liege)

51 Tagged spectator DIS off the deuteron as a tool to extract neutron structure

We present work on a model used to describe the process of tagged spectator DIS off the deuteron. The model uses a factorized approach and includes the effect of final-state interactions at intermediate to large Bjorken $x$ through effective rescattering amplitudes of the produced hadrons $X$ with the "spectator" nucleon. Comparisons with recent Jefferson Lab data are shown and discussed, also for the inclusive DIS case. We discuss the pole extrapolation method applied to the tagged spectator DIS process. This approach is based on the extrapolation of the measured cross sections at different momenta of the detected spectator proton to the non-physical pole of the bound neutron in the deuteron. The advantage of the method is that it makes it possible to suppress nuclear effects in a maximally model independent way. We apply the method to the recently measured BONuS data to extract the unpolarized neutron structure function at large $x$, and obtain a surprising $x$ dependence at $x \leq 0.6$, indicating the possibility of a rise in the neutron to proton structure function ratio. We discuss applications of the method at a possible EIC, both for the unpolarized and polarized case.

Speaker: Wim Cosyn

Cosyn_Poetic.pdf

52 Hadron multiplicities @ COMPASS

COMPASS recent results on hadron, pion and kaon multiplicities will be presented. The hadron and pion data show a good agreement with (N)LO expectations and some of these preliminary data have been already successfully incorporated in the global NLO fits to world data. However, the most important are kaon multiplicities, which can be used to extract kaon fragmentation functions. These are crucial in solving the so called ''strange quark polarization puzzle''. The COMPASS results are quite different from the expectations of the DSS fit. They also exhibit a tension with the HERMES results, the only other experiment which measured kaon multiplicities in SIDIS. Therefore, it is utmost important that these measurements are also continued in the future EIC.

Speaker: Marcin Stolarski (LIP Laboratorio de Instrumentacao e Fisica Experimental de Part)

stolarski.pdf.pdf

53 Intrinsic bottom and its impact on heavy new physics at the LHC

Heavy quark parton distribution functions (PDFs) play an important role in several Standard Model and New Physics processes. Most analyses rely on the assumption that the charm and bottom PDFs are generated perturbatively by gluon splitting and do not involve any non-perturbative degrees of freedom. On the other hand, non- perturbative, intrinsic heavy quark parton distributions have been predicted in the literature. We demonstrate that to a very good approximation the scale-evolution of the intrinsic heavy quark content of the nucleon is governed by non-singlet evolution equations. This allows to analyze the intrinsic heavy quark distributions without having to resort to a full-fledged global analysis of parton distribution functions. We exploit this freedom to model intrinsic bottom distributions which are so far missing in the literature. We estimate the impact of the non-perturbative contribution to the charm and bottom-quark PDFs and on several important parton-parton luminosities at the LHC.

Speaker: Dr Florian Lyonnet (SMU)

Intrinsic-Poetic.pdf

54 New developments in the statistical approach of parton distributions: tests and predictions up to LHC energies

The quantum statistical parton distributions approach proposed more than one decade ago is revisited by considering a larger set of recent and accurate Deep Inelastic Scattering experimental results. It enables us to improve the description of the data by means of a new determination of the parton distributions. This global next-to-leading order QCD analysis leads to a good description of several structure functions, involving unpolarized parton distributions and helicity distributions, in a broad range of $x$ and $Q^2$ and in terms of a rather small number of free parameters. There are several challenging issues and in particular the confirmation of a large positive gluon helicity distribution. The predictions of this theoretical approach will be tested for single-jet production and charge asymmetry in $W^{\pm}$ production in $\bar p p$ and $p p$ collisions up to LHC energies, using recent data and also for forthcoming experimental results.

Speaker: Prof. Jacques SOFFER (Physics Dept. TEMPLE University, Philadelphia, PA)

Poetic-15-soffer.pdf

Spin-3D Parallel

Spin-3D Parallel session

Convener: Daniel Boer (University of Groningen)

55 Results on longitudinal spin physics at COMPASS

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 NLO QCD fit to the world data to obtain the polarised parton distributions. Also an update on our results on the Bjorken sum rule, connecting the integral of the non-singlet spin-dependent structure function with the ratio of the weak coupling constants, will be given. Direct access to the gluon polarisation is possible via the photon gluon fusion process in semi-inclusive deep inelastic scattering. This process is studied using the $p_T$ dependence of charged hadron asymmetries. The latest results indicate a positive gluon polarisation in the kinematic region of COMPASS.

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

talk_wilfert.pdf

56 Probing Spin Dependent Quark and Gluon Distributions Through Azimuthal and Polarization Asymmetries

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 order. These amplitudes are probed in high energy leptoproduction processes through angular dependent cross sections and polarization asymmetries. The phenomenological extraction of the amplitudes and the distributions is a challenging task. We will present some models for the distributions in leptoproduction processes, as well as the observables that connect with the quark-nucleon helicity amplitudes for different Deeply Virtual production possibilities.

Speaker: Prof. Gary Goldstein (Tufts University)

1aaaaaaPOETIC2015_goldstein.pdf

1aaaaaaPOETIC2015_goldstein.pptx

57 GPDs in heavy mesons production and Compton scattering

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.

Speaker: Jakub Wagner (Institute for Nuclear Studies)

Wagner_POETIC6_final.pdf

58 The unpolarized TMD fragmentation function at two loops

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.

Speaker: Ignazio Scimemi (Universidad Complutense (ES))

Poetic2015Scimemi.pdf

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

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.

Speaker: Dr Alfredo Vega (Universidad de Valparaiso)

POETIC 2015 (Alfredo Vega).pdf

Thursday, 10 September

Small-x

Small-x session

Convener: Raju Venugopalan (Brookhaven National Laboratory)

60 Di-jet production and angular correlations in DIS at NLO

We compute the Next to Leading Order corrections to di-jet (di-hadron) production in DIS at small x using the Color Glass Condensate formalism. We study the azimuthal angular correlations between the two produced partons. (work in progress)

Speaker: Jamal Jalilian-Marian (Baruch College)

poetic-09-2015.pdf

61 Ultra-peripheral collisions and photoproduction with ALICE at the LHC: results and perspectives

Ultra-Peripheral Collisions (UPC) occur when the colliding particles are separated by impact parameters larger than the sum of their radii, and the interaction is mediated by the electromagnetic field. The ALICE Collaboration has studied exclusive photoproduction of $\rho^{0}$, J/$\psi$ and $\psi$(2S) vector mesons in Pb-Pb collisions at the LHC. Exclusive production of J/$\psi$ vector meson has also been studied in p-Pb collisions. The results of the aforementioned studies, along with the constraints that they set on the nuclear and nucleon gluon distributions, will be discussed. The study of the processes described above at higher statistics and higher energy with new data from LHC Run2 and the possible measurement of other processes, will also be presented during the talk.

Speaker: Daniele De Gruttola (Universita e INFN, Salerno (IT))

poetic6_2015_degruttola.pdf

62 Central Exclusive Production in pp collisions at LHCb

Proton-proton collisions at LHC energies usually produce hundreds of charged and neutral particles. However, when colourless propagators are involved and, in addition, the protons remain intact, this leads to a unique experimental signature of a small number of particles in the central region and two rapidity gaps that extend to the outgoing protons in the far-forward direction. Although designed with b-physics in mind, the LHCb detector is well suited to the detection and study of Central Exclusive Production (CEP) due to its ability to trigger and reconstruct low mass central systems, its good particle identification, its large pseudorapidity acceptance, and the running conditions of the LHC. Photoproduction of single JPsi, Psi(2S), and Upsilon mesons has been studied at fixed target colliders, at HERA, and most recently at the LHC in CEP through the colourless exchange of photons and pomerons. I will present recent results from LHCb which extend measurements of this process into a new kinematic regime and can be used to measure the gluon content of the proton at very small fractional momenta. The CEP of single Chi_c mesons, produced through Double Pomeron Exchange will be presented. Finally, I will present the first observation of a somewhat unexpected and experimentally dramatic signal: CEP of pairs of JPsi and Psi(2S) mesons. Prospects for the spectroscopy of low mass mesons producing pion and kaon pairs, as well as the potential for glueball and odderon searches will be discussed.

Speaker: Ronan Mcnulty (University College Dublin (IE))

cep_poetic.pdf

63 Gluon saturation with forward photons at LHC: prospects for a high-granularity calorimeter upgrade for ALICE

Direct photon production at forward rapidity is a promising probe for the gluon content of protons and nuclei at small x. In particular, the measurement of the nuclear modification factor for direct photons in p–A collisions at the LHC should provide a crucial test for gluon saturation. We discuss the unique role of such a photon measurement in the context of other measurements at the LHC and also of possible future measurements at EIC. To allow us to perform this measurement, a new forward calorimeter (FoCal) is proposed as an upgrade to the ALICE experiment. The proposed detector covers the range 3.5 < η < 5 which probes the gluon distributions at x ~ 10-5 and Q ~ pT > 4 GeV. We will discuss performance studies of such a detector, which demonstrate that extremely high-granularity calorimetry is required for a successful measurement, and show a few recent results from R&D for this project.

Speaker: Marco Van Leeuwen (Nikhef National institute for subatomic physics (NL))

15_Poetic_forward_fotons.pdf

15_Poetic_forward_fotons.pptx

10:40 Coffee Break

Coffee Break

PDFs

PDFs session

Convener: Markus Diehl (DESY)

64 Proton PDFs at the LHeC

The Large Hadron-Electron Collider LHeC is a proposed upgrade of the LHC to study ep/eA collisions in the TeV regime, by adding a 60 GeV electron beam through an Energy Recovery Linac. New evaluations are presented on the prospects for precisely determining the proton PDFs, with complete flavour unfolding in a single experiment, and the strong coupling constant with per mille accuracy.

Speaker: Claire Gwenlan (University of Oxford (GB))

POETIC6-LHeC-Gwenlan.pdf

65 Nuclear PDFs in eA collisions at the LHeC

The Large Hadron-Electron Collider LHeC is a proposed upgrade of the LHC to study ep/eA collisions in the TeV regime, by adding a 60 GeV electron beam through an Energy Recovery Linac. In this talk new results are presented on the physics prospects on energy frontier eA collisions with this machine, with emphasis new results on the precise determination of nuclear parton densities.

Speaker: Max Klein (University of Liverpool (GB))

klein.pdf

66 Lattice Calculation of Parton Distributions

We present results for our exploratory study for the direct evaluation of the parton distribution functions from lattice QCD. We present encouraging results using Nf = 2 + 1 + 1 twisted mass fermions with a pion mass of about 370 MeV, for unpolarized and polarized nonsinglet distributions. We also test the effect of gauge link smearing in the operator to estimate the influence of the Wilson line renormalization, which is yet to be done.

Speaker: Fernanda Steffens (DESY - Zeuthen)

steffens.pdf

12:15 Lunch Break

Lunch Break

Spin-3D

Spin-3D session

Convener: Marco Contalbrigo (Dipartimento di Fisica)

67 Overview of HERMES results

HERMES has collected a wealth of deep-inelastic scattering (DIS) data using the 27.6 GeV polarized lepton beam at HERA and various pure gas targets, both unpolarized and polarized. This allowed for a series of diverse and unique measurements. Among them are measurements that provide information on the three-dimensional structure of the nucleon both in momentum space and in position space. Results on azimuthal asymmetries from semi-inclusive DIS, sensitive to the former, will be presented as well as measurements of exclusive processes sensitive to position-space distributions. This will be complemented with the presentation of results on, among others, Bose-Einstein correlations and the measurement of $\Lambda$ polarization in quasi-real photoproduction.

Speaker: Dr Charlotte Van Hulse (University of the Basque Country)

poetic15.pdf

68 The gauge-invariant canonical energy-momentum tensor

The canonical energy-momentum tensor is often considered as a purely academic object because of its gauge dependence. However, it has recently been realized that canonical quantities can in fact be defined in a gauge-invariant way provided that strict locality is abandoned, the non-local aspect being dictacted in high-energy physics by the factorization theorems. Using the general techniques for the parametrization of non-local parton correlators, we provide for the first time a complete parametrization of the energy-momentum tensor (generalizing the purely local parametrizations of Ji and Bakker-Leader-Trueman used for the kinetic energy-momentum tensor) and identify explicitly the parts accessible from measurable two-parton distribution functions (TMDs and GPDs). As by-products, we confirm the absence of model-independent relations between TMDs and parton orbital angular momentum, recover in a much simpler way the Burkardt sum rule and derive three similar new sum rules expressing the conservation of transverse momentum.

Speaker: Cédric Lorcé (University of Liege)

POETIC2015.pdf

POETIC2015.pptx

69 Husimi distribution for nucleon tomography

The Wigner distribution is commonly used to define the phase space distribution of partons inside the nucleon. However, the Wigner distribution does not have a probabilistic interpretation because it is not positive definite. In pursuit of a positive phase space distribution in QCD, I suggest to use the Husimi distribution and discuss its properties.

Speaker: Dr Yoshitaka Hatta (Kyoto University)

Hatta.pdf

70 DIS on light nuclei with spectator tagging: New applications at intermediate and small x

An Electron-Ion Collider would enable next-generation measurements of DIS on light nuclei (deuteron, 3He, ...) with detection of nucleons and fragments in the nuclear fragmentation region ("spectator tagging"). Such measurements allow one to control the nuclear configuration during the high-energy process and could greatly advance our understanding in several areas of partonic structure and QCD: (a) precision measurements of neutron structure functions (including spin) in electron-deuteron scattering with proton tagging, eliminating nuclear binding through on-shell extrapolation in the recoil proton momentum; (b) controled studies of the nuclear modifications of quark and gluon densities (EMC effect, antishadowing), using the recoil momentum dependence to control the size of nuclear configurations; (c) novel studies of coherence and nuclear shadowing at x << 0.1 using tagged DIS. We present an overview of the physics applications of spectator tagging at intermediate and small x and comment on theoretical challenges and experimental requirements. We report about results of an R&D project aiming to demonstrate the feasibility of spectator tagging with EIC and quantify the physics impact.

Speaker: Christian Weiss (Jefferson Lab)

weiss15_poetic.pdf

71 Sketching the pion's valence-quark Generalised Parton Distribution

In order to learn effectively from measurements of Generalised Parton Distributions (GPDs), it is desirable to compute them using a framework that can potentially connect empirical information with basic features of the Standard Model. We sketch an approach to such computations, based upon a rainbow-ladder (RL) truncation of QCD's Dyson-Schwinger equations and exemplified via the pion's valence dressed-quark GPD. Our analysis focuses primarily on vanishing skewness, although we also capitalise on the symmetry-preserving nature of the RL truncation by connecting the considered pion GPD with the pion's valence-quark parton Distribution Amplitude. We explain that the impulse-approximation used hitherto to define the pion's valence dressed-quark GPD is generally invalid owing to omission of contributions from the gluons which bind dressed-quarks into the pion. A simple correction enables us to identify a practicable improvement to the approximation for the pion GPD at vanishing skewness, expressed as the Radon transform of a single amplitude. Therewith we obtain results for the associated impact-parameter dependent distribution, which provides a qualitatively sound picture of the pion's dressed-quark structure at an hadronic scale. We evolve the distributions to the scale 2\,GeV, so as to facilitate comparisons in future with results from experiment or other nonperturbative methods.

Speaker: Hervé MOUTARDE

moutarde_poetic_2015_09_10.pdf

Information

Information

Convener: Marco Contalbrigo (Dipartimento di Fisica)

72 Banquet information

I will give information about thurday evening's banquet.

Speaker: Franck Sabatié (CEA Saclay)

Banquet_FS.pdf

16:00 Free time in Paris

Free time in Paris

Conference Banquet: Restaurant du Sénat

Conference Dinner

Friday, 11 September

Spin-3D Parallel

Spin-3D Parallel session

Convener: Michel Garçon

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

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 nucleon. Timelike Compton Scattering (TCS) correspond to the reaction γN->γ*N->e+e-N, where the photon is scattered off a quark. It is measured through its interference with the associated Bethe-Heitler process, which has the same final state. TCS allows to access the GPDs and test their universality by comparison to the results obtained with the DVCS process (eN->eγN). Also, results obtained with TCS provide additional independent constrains to the GPDs parameterization. We will present the physical motivations for TCS, with our theoretical predictions for TCS observables and their dependencies. We calculated for JLab 12 GeV energies all the single and double beam and/or target polarization observables off the proton and off the neutron. We will also present the experimental perspectives for the next years at JLab. Two proposals were already accepted at JLab : in Hall B, with the CLAS12 spectrometer, in order to measure the unpolarized cross section and in Hall A, with the SoLID spectrometer, in order to measure the unpolarized cross section and the beam spin asymmetry at high intensity. A Letter Of Intent was also submitted in order to measure the transverse target spin asymmetries in Hall C. We will discuss the merits of this different experiments and present some of the expected results.

Speaker: Marie BOER

boer.pdf

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

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.

Speaker: Renaud Boussarie (LPT Orsay)

BoussariePoetic6.pdf

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

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

Speaker: maxime defurne

defurne.pdf

76 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

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) hard process in semi-inclusive DIS or quark-gluon (gluon-gluon) hard scattering are enhanced in nucleon-nucleon interaction. This can be achieved by studying spin dependent asymmetries in production of hadrons at high transverse momentum $p_T$. RHIC has recently measured such double spin asymmetries $A_{LL}(p_T)$ for pion production at high center of mass energies, and inclusion of its data to global fits based on NLO collinear pQCD calculations gives some constraints on the gluon polarization in the range $0.05 \lt x_G \lt 0.2$ [1]. The validity of the calculations of partonic cross sections at NLO has recently been extended to COMPASS at lower center of mass energies by adding leading-log gluon resummation in the unpolarized case [2]. The calculations reproduce now within scale uncertainty the cross section for single hadron production as a function of p_T measured recently at COMPASS [3]. Once extended to the polarized case, $A_{LL}(p_T)$ measurements at COMPASS can also be used to constrain the gluon polarization without large uncertainties about validity of the NLO pQCD framework at COMPASS energies. We will present preliminary COMPASS results on double longitudinal spin asymmetries $A_{LL}(p_T)$ for single hadron production measured on the deuteron and the proton at $Q^2 \lt 1$ GeV$^2$, $p_T \gt 1$ GeV/c and center of mass energy $\sqrt{s}=18$ GeV. These asymmetries are computed separately for three bins in pseudorapidity to improve the sensitivity to the gluon polarization. All COMPASS data taken from 2002 to 2011 by scattering 160 GeV polarized muons on longitudinally polarized 6LiD and NH3 targets have been used, and the number of hadrons collected with $p_T \gt 1$ GeV/c for this analysis amounts to about 60 million. The obtained asymmetries will be compared to theoretical predictions at NLO without gluon resummations. These results will be supplemented by a prospect study on a similar analysis at EIC. [1] E.C. Aschenauer et al., arXiv:1304.0079 [nucl-ex]. [2] D.P. Anderle, F. Ringer and W. Vogelsang, Phys. Rev. D87 (2013) 034014. [3] C. Adolph et al., (COMPASS collaboration), Phys. Rev. D88 (2013) 091101.

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

poetic_levillain.pdf

77 Non-dipolar Wilson links for transverse-momentum-dependent wave functions

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 singularity from Wilson-link self-energy corrections is alleviated to a logarithmic one. In particular no soft function is needed, when the two pieces of Wilson links are orthogonal to each other. We show explicitly at one-loop level that the simpler definition with the non-dipolar Wilson links exhibits the same infrared behavior as the one with the dipolar Wilson links and complicated soft subtraction. It is pointed out that both definitions reduce to the naive TMD wave function as the non-light-like Wilson links approach to the light cone. Their equivalence is then extended to all orders by considering the evolution in the Wilson-link rapidity.

Speaker: Dr Yu-Ming Wang (TU Munich)

pion.pdf

pp-pA-AA Parallel

pp-pA-AA Parallel session

Convener: Javier L Albacete (Universidad de Granada)

78 Forward J/psi production in pA collisions at the LHC

Inclusive production of J/psi mesons, especially at forward rapidities, is an important probe of small-x gluons in protons and nuclei. In this work we re-evaluate the production cross sections in the Color Glass Condensate framework, where the process is described by a large x gluon from the probe splitting into a quark pair and eikonally interacting with the target proton or nucleus. Using a standard collinear gluon distribution for the probe and an up to date dipole cross section fitted to HERA data to describe the target we achieve a rather good description of the cross section in proton-proton collisions, although with a rather large normalization uncertainty. More importantly, we show that generalizing the dipole cross section to nuclei in the Glauber approach results in a nuclear suppression of J/psi production that is much closer to the experimental data than claimed in previous literature.

Speaker: Bertrand Ducloue (University of Jyvaskyla)

Ducloue_Poetic6.pdf

79 D^* and B^* Mesons in Strange Hadronic Medium at Finite Temperature.

We calculate the effect of density and temperature of isospin symmetric strange medium on the shift in masses and decay constants of vector D and B mesons using chiral SU(3) model and QCD sum rule approach. In the present investigation the values of quark and gluon condensates are calculated from the chiral SU(3) model and these condensates are further used as input in the QCD Sum rule framework. These condensates are further used to calculate the in medium masses and decay constants of vector D and B mesons. These in medium properties of vector D and B mesons will be helpful to understand the experimental observables of the experiments like CBM and PANDA under FAIR project at GSI, Germany. The results which are observed in present work are also compared with the previous predictions.

Speaker: Mr Rahul Chhabra (Dr. B R Ambedkar National Institute of Technology Jalandhar, Punjab India)

chhabra.pdf

chhabra.pptx

80 Thermalization of mini-jets in a quark-gluon plasma

We complete the physical picture for the evolution of a high-energy jet propagating through a weakly-coupled quark-gluon plasma by investigating the thermalization of the soft components of the jet. We argue that the following scenario should hold: the leading particle emits a significant number of mini-jets which promptly evolve via quasi-democratic branchings and thus degrade into a myriad of soft gluons, with energies of the order of the medium temperature $T$. Via elastic collisions with the medium constituents, these soft gluons relax to local thermal equilibrium with the plasma over a time scale which is considerably shorter than the typical lifetime of the mini-jet. The thermalized gluons form a tail which lags behind the hard components of the jet. We support this scenario, first, via parametric arguments and, next, by studying a simplified kinetic equation, which describes the jet dynamics in longitudinal phase-space. We solve the kinetic equation using both (semi-)analytical and numerical methods. In particular, we obtain the first exact, analytic, solutions to the ultrarelativistic Fokker-Planck equation in one-dimensional phase-space. Our results confirm the physical picture aforementioned and demonstrate the quenching of the jet via multiple branching followed by the thermalization of the soft gluons in the cascades.

Speaker: Dr Bin Wu (IPhT Saclay)

bin-wu.pdf

81 $X(3872)$ production in high energy heavy ion collisions

We determined the production cross sections of the X(3872) state in the reactions DD→πX, D¯∗D→πX and D¯∗D∗→πX. We construct a formalism considering X as a molecular bound state of D¯0D∗0−c.c, D−D∗+−c.c and D−sD∗+s−c.c. To obtain the amplitudes related to these processes we have made use of effective field Lagrangians. We have evaluated the cross section for the reaction D¯∗D→πX, and find that the diagrams involving the XD¯∗D∗ vertex give a large contribution. We also estimate the XD¯∗D∗ coupling, which turns out to be 1.95±0.22. We then use it to obtain the cross section for the reaction D¯∗D∗→πX and find that, in this case too, the XD¯∗D∗ vertex is relevant. We also discuss the role of the charged components of X in the determination of the production cross sections.

Speaker: Dr Marina Nielsen (Universidade de São paulo)

paris15_nielsen.pdf

82 Holographic approaches of thermalization in confining geometries

Confinement is a strongly coupled phenomenon that can be studied using non perturbative methods such as lattice QCD. However, the more interesting case of time dependent transitions from confining configurations to thermalization, as it is the case in heavy ion collisions, requires different approaches. In this talk, a first attempt, in the context of AdS/CFT, to study such processes will be presented. AdS/CFT allows the mapping and studying of non perturbative processes of gauge theories by solving differential (Einstein) equations with prescribed boundary conditions. The idea is then the following: one begins with initial data of a geometry that corresponds to a confining gauge theory and injects energy into the system at time t=0. The goal is to follow the evolution of the system in time; the set up is thus a Cauchy initial value problem. The main purpose of the paper is to answer the question whether and under which circumstances the geometry will eventually collapse into a black hole, which mimics thermalization in the field (gauge) theory side.

Speaker: Anastasios Taliotis

Paris_LAST_TALK_09_15.pdf

Paris_LAST_TALK_09_15.pptx

10:40 Coffee Break

Coffee Break

Future facilities Parallel

Future facilities Parallel session

Convener: Charles Hyde (Old Dominion University)

83 A dedicated eRHIC Detector design

Construction of an Electron-Ion Collider with luminosities exceeding $10^{33} cm^{−1}s^{−1}$ is becoming a project of highest priority for the US Nuclear Physics community. The main physics topics to be explored at this new facility are (i) the polarized sea quark and gluon distributions in the nucleon, (ii) QCD dynamics of the low-x, high density gluon regime, (iii) hadronization and energy loss in the nuclear medium [1]. One of the considered construction options is the addition of a high-energy polarized electron beam to the existing RHIC hadron machine, converting it into an Electron-Ion Collider (eRHIC) [2]. A dedicated eRHIC detector, designed to efficiently register and identify deep inelastic electron scattering (DIS) processes in a wide range of center-of-mass energies available with the new collider is one of the key elements of such an upgrade. The progress on the detector design work will be shown, and the simulation results presented. [1] A. Accardi et al., "Electron Ion Collider: The Next QCD Frontier - Understanding the glue that binds us all" (EIC White Paper), arXiv:1212.1701v3 (2014). [2] E.C. Aschenauer et al., "eRHIC design study (An Electron-Ion Collider at BNL)", arXiv:1409.1633 (2014).

Speaker: Dr Alexander Kiselev (Brookhaven National Lab)

ayk-2015-09-11-poetic2015.pptx

84 The low Q2 chicane and Compton polarimeter at the JLab mEIC

The mEIC features a low Q2 chicane in order to be able to study reaction involving quasi-real photon. A dipole is placed on the beam in order to provide momentum analysis of the electrons associated with those photons. A chicane geometry is thus created by addind 3 additional dipoles in order to bring the beam back in the ring. This chicane configuration is also ideal for Compton polarimetry since the sppin precession is cancelled in the middle of the chicane where a photon source will be added to measure the Compton process. I will present the layout of the the low Q2 chicane and some parameters relevant to the low Q2 tagger and the Compton detectors designs.

Speaker: Alexandre Camsonne (Jefferson Laboratory)

POETIC-2015-mEIC-Compton-Low-Q2-camsonne.pdf

85 Interaction region design and auxillary detector systems for an EIC

There are a number of exciting physics opportunities at a future electron-ion collider facility. One possible design for such a facility is eRHIC, where the current RHIC facility located at Brookhaven National Lab would be transformed into an electron-ion collider. It is imperative for a seamless integration of auxiliary detector systems into the interaction region design to have a machine that meets the needs for the planned physics analyses, as well as take into account the space constraints due to the tunnel geometry and the necessary beam line elements. In this talk, we describe the current ideas for integrating a luminosity detector, electron polarimeter, roman pots, and a low $\mbox{Q}^{2}$-tagger into the interaction region for eRHIC.

Speaker: Dr Richard Petti (Brookhaven National Lab)

irDesignPoetic2015_petti_v2.pdf

86 A study of neutron structure with (un)polarized deuterons and forward spectator tagging at EIC

An Electron-Ion Collider (EIC) would enable measurements of neutron structure through deep-inelastic electron-deuteron scattering with coincidence tagging of the forward-moving spectator proton (``spectator tagging''). This technique allows one to positively identify the active neutron and control its quantum state in the deuteron through measurement of the recoil proton momentum. A R&D project at Jefferson Lab has established the feasibility of spectator tagging, including measurements of neutron spin structure with a polarized deuteron beam. In this study, we developed a Monte Carlo simulation on the GEANT4 modular framework with the physical processes and the MEIC accelerator and detector/IR/forard tagger design and used to optimize the analysis strategy. A novel technique is implemented for obtaining the free neutron structure function by extrapolating the measured recoil momentum distributions to the on-shell point. Such measurements provide essential information for the flavor separation of the nucleon parton densities, the nucleon spin decomposition, and precision studies of QCD evolution in the flavor-singlet and non-singlet sectors. The EMC effect in light nuclei can be elucidated by studying the recoil momentum dependence of the nuclear modification away from the on-shell point. In this talk we describe the proposed experimental setup and analysis procedure, and present results of a model-independent extraction of the free neutron structure through on-shell extrapolation, both for the unpolarized (F_2n) and the polarized neutron structure functions (g_1n).

Speaker: Dr Kijun Park (Old Dominion University)

LDRD_SpecTag_POETIC2015_KPark.pdf

Small-x Parallel

Small-x Parallel session

Convener: Stephane Munier (Ecole polytechnique)

87 Gluon saturation in leading neutron production

We study the Feynman $x_F$ distribution of leading neutrons produced in $e + p \rightarrow e + n + X$ reactions. Using the factorization approach, we write the differential cross section in terms of the pion flux and the pion - photon total cross section. The latter is related to the dipole scattering amplitude, which contains information about the QCD nonlinear effects and gluon saturation. With the parameters strongly constrained by other phenomenological information, we are able to reproduce the recently released H1 leading neutron spectra. We show that in future electron-proton colliders, these spectra could help us to observe more clearly gluon saturation effects.

Speaker: Dr Fernando Navarra (Institute of Physics - University of Sao Paulo)

poetic-navarra.pdf

88 Di-photon correlations in dilute-dense collisions from the CGC

I will discuss in details whether there is a ridge like structure in di-photon correlations in high-multiplicity events in p+p and p+A collisions at the LHC. Such measurements at the LHC and future colliders provides useful complementary information about the underlying dynamics of particle production in high-multiplicity events, and help to understand the true nature of the observed ridge phenomenon in di-hadron production at the LHC.

Speaker: Amir Rezaeian (Universidad Tecnica Federico Santa Maria)

Poetic15_Rezaeian.pdf

89 Elliptic azimuthal anisotropy and the distribution of linearly polarized gluons in DIS dijet production at high energy

We determine the distribution of linearly polarized gluons of a dense target at small $x$ by solving the JIMWLK rapidity evolution equations. From these solutions we estimate $\sim \cos 2\phi$ azimuthal asymmetries in DIS dijet production at high energies. We find sizeable long-range in rapidity azimuthal asymmetries with a magnitude in the range of $v_2=\langle\cos2\phi\rangle\sim 10\%$.

Speaker: Adrian Dumitru (Baruch College (City University of New York))

DijetDIS_POETIC_VI.pdf

90 Numerical precision of the running coupling Balitsky-Kovchegov equation solution

We use the running coupling Balitsky–Kovchegov (rcBK) equation to study the rapidity dependence of saturation in inclusive HERA data and we discuss the behaviour of it’s numerical solution. The rcBK equation has been solved using Runge–Kutta methods. The influence of the parameters implicit in the numerical evolution has been studied. They include, among others, the order of the Runge–Kutta evolution, the size of the different grids and the step in the numerical evolution. Some suggestions on the minimum value of these parameters are put forward. Also the dependence of the rcBK solution on the shape of initial conditions will be addressed.

Speaker: Marek Matas (FNSPE CTU in Prague)

Marek Matas.pdf

12:20 Lunch Break

Lunch Break

pp-pA-AA

pp-pA-AA session

Convener: Francois Arleo (Laboratoire Leprince-Ringuet)

91 What do we need an eA collider for: questions from pp, pA and AA

I will argue that full understanding of pp, pA and AA data requires input from an eA by discussing specific open questions that have arisen in pp, pA and AA collisions at the LHC.

Speaker: Guilherme Teixeira De Almeida Milhano (Instituto Superior Tecnico (PT))

MIlhano_Poetic.pdf

92 Quark-Hadron Transition and Hadronization Studies at an EIC

An Electron Ion Collider (EIC) as a future facility for Nuclear Physics is expected to be the vehicle for Nuclear science to reach the next QCD frontier. The EIC will offer a versatile range of kinematics, beam polarization, beam species and will exceed by orders of magnitudes the luminosities previously available at HERA. These uniques capabilities will be essential in unraveling the mysteries of visible matter. Understanding the complex structure of nuclei and their formation in QCD as well as their roles as QCD laboratories will be at the heart of the EIC science mission. In this talk, we will focus on possible studies of the propagation of a color charge in the nuclear medium. We will emphasize the importance of using the nucleus as a femtometer filter with variable sizes in shedding new light on hadronization dynamics and its possible dependence on the nature and kinematics of the fast moving color.

Speaker: Kawtar Hafidi

Hadronization-Hafidi.pdf

93 Multiparton interactions in pp collisions: between bug and feature

In high-energy proton-proton collisions, interactions between "spectator partons" are inevitable. Collisions with two hard parton-level scatters can contribute to important channels at the LHC. This mechanism probes interesting aspects of hadron structure, with several relations to EIC physics. I give an introduction to multiparton scattering and highlight some some of these aspects.

Speaker: Markus Diehl (DESY)

poetic.pdf

94 Color fluctuation phenomena in photon(proton) – nucleus collisions

We explain that a wide range of high energy nuclear phenomena is related to the phenomenon of fluctuations of strength of interaction of the projectile with nucleons (color fluctuations) and large coherence length of the interaction. Connection of the color fluctuation phenomenon to the mechanism of the leading twist shadowing is reviewed, predictions of the theory are compared to the first LHC data. The key role of the studies of ultra peripheral collisions at the LHC for the progress in the field is emphasized. Evidence for the x-dependent color fluctuations in nucleons is presented.

Speaker: Mark Strikman (Penn State University)

strikman.key

strikman.pdf

95 Electro- and hadro-production of charmonia off nuclei

Charmonia produced on nuclear targets have always been a supplier of unexpected effects and puzzles. While some of them seem to be well understood, many others are still under debate. New precise measurements of electron-ion collisions are expected settle these challenging problems.

Speaker: Boris Kopeliovich (UTFSM)

kopeliovich.pdf

15:50 Coffee Break

Coffee Break

Closing Talks

Convener: Cyrille Marquet (CPHT - Ecole Polytechnique)

96 Physics opportunities at an EIC beyond the White paper

In this talk several physics opportunities at an EIC beyond the key measurements discussed in the EIC White paper will highlighted. For some measurements first studies will be presented.

Speaker: elke-caroline Aschenauer (BNL)

eca.EIC.newIdeas.pptx

97 Trying to understand high energy hadronic physics

Speaker: Prof. Alfred Mueller (Columbia University)