 Nucleon spin structure and Imaging in the Valence quark region ➥ Inclusive measurements at large x; quark models tests and Lattice QCD tests ➥ Exclusive measurements in the valence region (imaging): DVCS + DVMP + Lattice to create an image. ➥ Semi-inclusive measurements (dynamical imaging)  Nucleon spin structure at an EIC ➥ Inclusive measurements at lower x (evolution of g 1, first moment, and g 2 ) ➥ Exclusive measurement (Imaging of the glue and the sea ) ➥ Semi-inclusive measurements (dynamical imaging with a focus on the sea and glue) June 20-24, 2011PacSPIN2011, Cairns, QLD, Australia OUTLINE: Zein-Eddine Meziani Temple University Spin at JLab 12 GeV and EIC 1

Some of the NSAC LRP Overarching QCD questions (December 2007) What is the internal spin and flavor landscape of hadrons? What is the role of gluons and gluons self interactions in nucleon and nuclei? What governs the transition of quarks and gluons into pions and nucleons? June 20-24, 2011PacSPIN2011, Cairns, QLD, Australia2

The Tools June 20-24, 2011PacSPIN2011, Cairns, QLD, Australia GPDs and TMDs in Nuclei Exclusive Semi-inclusive Initial and final medium effects Inclusive Sum rules and polarizabilities Generalized Parton Distributions Exclusive reactions Elastic form factors Deep Virtual Compton Scattering Deep Virtual Meson Production Transverse Momentum Distributions Semi-Inclusive DIS Distributions and Fragmentation functions Electroweak Physics/probe Beyond the standard Model/or a probe to hadronic systems QCD Since 1998Since

Resolution of the probe and scale of theory tools Q2Q2 Lattice QCD pQCD 0110∞ Models June 20-24, 2011PacSPIN2011, Cairns, QLD, Australia4

12 GeV Upgrade Project12 GeV Upgrade Project June 20-24, 2011 PacSPIN2011, Cairns, QLD, Australia Upgrade is designed to build on existing facility: vast majority of accelerator and experimental equipment have continued use New Hall Add arc Enhanced capabilities in existing Halls Add 5 cryomodules 20 cryomodules Scope of the project includes: Doubling the accelerator beam energy New experimental Hall and beamline Upgrades to existing Experimental Halls Maintain capability to deliver lower pass beam energies: 2.2, 4.4, 6.6…. Upgrade arc magnets and supplies CHL upgrade 5

Hall B – understanding nucleon structure via generalized parton distributions Hall C – precision determination of valence quark properties in nucleons and nuclei Hall A – future new experiments (e.g. PVDIS with SOLID and Moller) 12 GeV Spin Physics Capabilities PacSPIN2011, Cairns, QLD, AustraliaJune 20-24, 20116

PacSPIN2011, Cairns, QLD, Australia SOLID for PVDIS: High Luminosity on LD2 and LH2 Better than 1% errors for small bins Large Q 2 coverage x-range W 2 > 4 GeV 2 SOLID for SIDIS: High luminosity on polarized 3 He Better than 1% errors for small bins Large Q 2 coverage x-range W 2 > 4 GeV 2 June 20-24, 20117

PacSPIN2011, Cairns, QLD, Australia Polarized Structure functions 8

A 1 n and Helicity-Flavor Decomposition June 20-24, 2011PacSPIN2011, Cairns, QLD, Australia JLab E

Effect of considering transverse momentum of quarks in the nucleon Inclusive Hall A and B and Semi-Inclusive Hermes Avakian, Brodsky, Deur and Yuan Phys.Rev.Lett.99:082001,2007. BBS BBS+OAM June 20-24, 2011PacSPIN2011, Cairns, QLD, Australia10

A 1 n at 11 GeV Hall C Inclusive double spin asymmetries using 12 GeV W>1.2 CLAS12 Proton June 20-24, 2011PacSPIN2011, Cairns, QLD, Australia11

Longitudinal Double Spin Asymmetry in SIDIS E e =11 GeV NH 3 and 3 He Asymmetry measurements with different hadrons (  ) and targets (p,n) allows for flavor separation At JLab 12 GeV with SIDIS June 20-24, 2011PacSPIN2011, Cairns, QLD, Australia12

Quark Gluon Correlations June 20-24, 2011PacSPIN2011, Cairns, QLD, Australia13

Average Color Lorentz Force ( M. Burkardt ) June 20-24, 2011PacSPIN2011, Cairns, QLD, Australia14

Projected g 2 n points are vertically offset from zero along lines that reflect different (roughly) constant Q 2 values from 2.5—7 GeV 2. g 2 for 3 He is extracted directly from L and T spin-dependent cross sections measured within the same experiment. Strength of SHMS/HMS: nearly constant Q 2 (but less coverage for x < 0.3)

3D imaging of the nucleon Tool: Generalised Parton Distributions Form factors: Fourier transform of e.g. a radial charge distribution Parton Distrribution Functions: Number density of quarks with longitudinal momentum fraction x GPDs: Generalized description in 2+ 1 dimensions June 20-24, 2011PacSPIN2011, Cairns, QLD, Australia16

Theoretical Framework in QCD Generalized Parton Distributions – Matrix elements of non-local operators with quarks and gluon field – Depend on two longitudinal momentum fractions – For unpolarized quarks we have two distributions: H q conserves proton helicity E q flips proton helicity June 20-24, 2011PacSPIN2011, Cairns, QLD, Australia17

Nucleon Angular Momentum Sum Rule June 20-24, 2011PacSPIN2011, Cairns, QLD, Australia Ji Sum rule (1997) Spin of quarks contribution Orbital angular momentum of quarks Total angular momentum of gluons 18

June 20-24, 2011PacSPIN2011, Cairns, QLD, Australia19

The handbag dominance: k k’ q’ Factorization Theorem GPDs x+  x-  t k pp’ k’ q’ pp’ amplitude Deeply Virtual Compton Scattering is the simplest hard exclusive process involving GPDs Model by Goeke, Polyakov, Vanderhaeghen Generalized Parton Distributions, Deeply Virtual Compton Scattering June 20-24, 2011PacSPIN2011, Cairns, QLD, Australia20

GPDs : 3D quark/gluon imaging of nucleon Fourier transform of GPDs : simultaneous distributions of quarks w.r.t. longitudinal momentum x P and transverse position b theoretical parametrization needed : double distributions, dual param. (Guzey), conformal param. (M üller) ( M. Burkardt )

June 20-24, 2011PacSPIN2011, Cairns, QLD, Australia Peter Kroll 22

JLab Upgrade Upgraded JLab has complementary & unique capabilities High x B only reachable with high luminosity H1, ZEUS and High luminosity required Valenceregion JLab12 Sea/gluonregion EIC Large phase space ( ,t,Q 2 ) June 20-24, 2011PacSPIN2011, Cairns, QLD, Australia23

June 20-24, 2011 PacSPIN2011, Cairns, QLD, Australia t hard vertices A = Δ           = Unpolarized beam, transverse target: Δ  UT ~ sin  {k(F 2 H – F 1 E ) }d  E (  t) Δ  LU ~ sin  {F 1 H + ξ(F 1 +F 2 ) H +kF 2 E }d  ~ Polarized beam, unpolarized target: H ( ,t ) ξ=x B /(2-x B ) Unpolarized beam, longitudinal target: Δ  UL ~ sin  {F 1 H +ξ(F 1 +F 2 )( H +ξ/(1+ξ) E) }d  ~ H ( ,t ) ~ Cleanest process: Deeply Virtual Compton Scattering k = -t/4M 2 ep ep  global analysis : cross sections, asymmetries, (p,n), ( γ,M) 24

L = 1x10 35 T = 2000 hrs Δ Q 2 = 1 GeV 2 Δ x = 0.05 E = 11 GeV Selected Kinematics Δ  LU ~sin  Im{F 1 H +.  }d  e p ep  Projected results exclusive DVCS : JLab 12 GeV Avakian June 20-24, 2011PacSPIN2011, Cairns, QLD, Australia CLAS12 25

 Asymmetry highly sensitive to the u-quark contributions to proton spin. Transverse polarized target e p ep  Δ  ~ sin  Im{k 1 (F 2 H – F 1 E ) +…}d  Q 2 =2.2 GeV 2, x B = 0.25, -t = 0.5GeV 2 E = 11 GeV Projected results A UTx Target polarization in scattering plane A UTy Target polarization perpedicular to scattering plane Exclusive DVCS on transverse JLab 12 GeV June 20-24, 2011PacSPIN2011, Cairns, QLD, Australia26

exclusive ρ 0 production on transverse target T          t/4m 2 ) - Re      UT  A ~ 2H u + H d B ~ 2E u + E d 00 Q 2 =5 GeV 2 E u, E d needed for angular momentum sum rule. 00 A ~ H u - H d B ~ E u - E d ++ Goeke, Polyakov, Vdh (2001) Projected results data June 20-24, 2011PacSPIN2011, Cairns, QLD, Australia27

Quark Angular Momentum June 20-24, 2011 PacSPIN2011, Cairns, QLD, Australia → Access to quark orbital angular momentum Total angular momentum of gluons 28

TMDs 12 GeV in Hall B and Dynamical Imaging June 20-24, 2011 PacSPIN2011, Cairns, QLD, Australia E : E : Pion SIDIS E : E : Kaon SIDIS E : E : Pion SIDIS E : E : Kaon SIDIS LOI : LOI : Pion SIDIS LOI : LOI : Kaon SIDIS PAC approved experiments & LoI N q U L T  Complete program of TMDs studies for pions and kaons  Kaon measurements crucial for a better understanding of the TMDs “kaon puzzle”  Kaon SIDIS program requires an upgrade of the CLAS12 detector PID RICH detector to replace LTCC Project under development 29

Hall A Transversity Projected Data Using SOLID  Total 1400 bins in x, Q 2, P T and z for 11/8.8 GeV beam.  z ranges from 0.3 ~ 0.7, only one z and Q 2 bin of 11/8.8 GeV is shown here. π + projections are shown, similar to the π -. June 20-24, 2011PacSPIN2011, Cairns, QLD, Australia30

Tool: Generalised Parton Distributions Generalized description in 2+ 1 dimensions Valence quark imaging of the nucleon is one goal of JLab at 12 GeV.  Gluon imaging is still missing  Sea Quarks imaging is also missing  Total Spin of the nucleon in terms of all of its constituents. June 20-24, 2011PacSPIN2011, Cairns, QLD, Australia 3-D quark imaging of the nucleon; What‘s missing 31

Luminosity~ few cm -1 s -1 June 20-24, 2011PacSPIN2011, Cairns, QLD, Australia32

EIC Kinematic Coverage June 20-24, 2011 PacSPIN2011, Cairns, QLD, Australia ep mEIC: eA mEIC: 3+30/11+30 (0.04<y<0.6) eA eLIC: (y=0.6) EIC connects JLab and HERA kinematic region 33

Gluon Imaging with exclusive processes June 20-24, 2011PacSPIN2011, Cairns, QLD, Australia Goal: Transverse gluon imaging of nucleon over wide range of x: < x < 0.1 Two-gluon exchange dominant for J/ , φ,  production at large energies  sensitive to gluon distribution squared! LO factorization ~ color dipole picture  access to gluon spatial distribution in nuclei Fit with d  /dt = e -Bt Measurements at DESY of diffractive channels ( J/ , , , γ ) confirmed the applicability of QCD factorization: t-slopes universal at high Q 2 flavor relations  :  Hard exclusive processes provide access to transverse gluon imaging at EIC! A.Levy(hep: ) 34

Nucleon Spin Sum Rule ➥ Through the momentum sum rule and HERA DVMP with J/Psi data we have a glimpse on GPD H g ➥ Nothing is known about GPD E g June 20-24, 2011PacSPIN2011, Cairns, QLD, Australia Ji Sum rule (1997) Spin of quarks Contribution: Measured in DIS Orbital angular momentum of quarks: Input from Lattice and measurements at JLab 12 GeV Total angular momentum of gluons 35

“My“ Golden Experimental Program Glue imaging using unpolarized targets and accessing gluon GPD H through exclusive meson production in the valence region Transversely polarized nucleon to access gluon GPD E and the Spin Sum Rule. June 20-24, 2011PacSPIN2011, Cairns, QLD, Australia36

Transversity and the Tensor Charge Quark transverse polarization in a transversely polarized nucleon: – Can be probed in Semi-Inclusive DIS, Drell-Yan processes. – Does not mix with gluons, has valence like behavior. – Nucleon tensor charge can be extracted from the lowest moment of h 1 and compared to LQCDcalculations June 20-24, 2011PacSPIN2011, Cairns, QLD, Australia Nucleon Spin Quark Spin h 1T = Tensor Charge 37

Projections with 3 He (neutron) June 20-24, 2011PacSPIN2011, Cairns, QLD, Australia GeV 72 days GeV 36 days GeV 72 days 12 GeV SoLid 3 He : 87% effective polarization Equal stat. for proton and neutron (combine 3 He and D) GeV GeV3+20 GeV P36 d (3x10 34 /cm 2 /s)36 d (1x10 34 /cm 2 /s) D72 d 3 He72 d 38

3-D momentum structure the nucleon: Dipole pattern due to Sivers effect June 20-24, 2011PacSPIN2011, Cairns, QLD, Australia ( Plot from Prokudin; red: positive effect, blue: negative effect) 39

Proton π + (z = ) June 20-24, 2011PacSPIN2011, Cairns, QLD, Australia40

Summary  JLab 12 GeV will enhance significantly our knowledge of nucleon spin structure in valence region.  A high polarized luminosity EIC with variable energy will be a natural extension for achieving full imaging of the nucleon including the glue and the sea.  More than one interaction region in the EIC is important for complementarity of explored physics (exclusive vs semi- inclusive) and confirmation of discoveries. A range of s from 200 to 4000 GeV 2 would be desirable But a luminosity above cm -2 s -1 is a must June 20-24, 2011PacSPIN2011, Cairns, QLD, Australia41