Selected Physics Topics at the Electron-Ion-Collider Antje Bruell, JLab ECT workshop, July 2008 nuclear effects in deep inelastic scattering from fixed target experiments prospects for EIC TMDs and GPDs at EIC Summary

x and A dependence of the EMC effect

Q2 dependence of the EMC effect

NMC vs E665 nuclear data

NMC experimental set-up cancellation of acceptance and luminosity

Gluon Saturation at EIC ? Gluon distribution G(x,Q2) What can we measure at EIC ? Extract from scaling violation in F2: dF2/dlnQ2 FL ~ as G(x,Q2) Other Methods: 2+1 jet rates (needs jet algorithm and modeling of hadronization for inelastic hadron final states) inelastic vector meson production (e.g. J/) diffractive vector meson production - very sensitive to G(x,Q2)

Gluon Saturation at EIC ?

The Gluon Contribution to the Nucleon Spin Antje Bruell, Jlab EIC meeting, MIT, April 7 2007 Introduction G from scaling violations of g1(x,Q2) The Bjorken Sum Rule G from charm production

The Gluon Contribution to the Nucleon Spin Antje Bruell, Jlab EIC meeting, MIT, April 7 2007 Introduction G from scaling violations of g1(x,Q2) The Bjorken Sum Rule G from charm production

The Gluon Contribution to the Nucleon Spin Antje Bruell, Jlab EIC meeting, MIT, April 7 2007 Introduction G from scaling violations of g1(x,Q2) The Bjorken Sum Rule G from charm production

The Gluon Contribution to the Nucleon Spin Antje Bruell, Jlab EIC meeting, MIT, April 7 2007 Introduction G from scaling violations of g1(x,Q2) The Bjorken Sum Rule G from charm production

Exclusive Processes: Collider Energies

Exclusive Processes: EIC Potential and Simulations

The Gluon Contribution to the Nucleon Spin Antje Bruell, Jlab EIC meeting, MIT, April 7 2007 Introduction G from scaling violations of g1(x,Q2) The Bjorken Sum Rule G from charm production

The Gluon Contribution to the Nucleon Spin Antje Bruell, Jlab EIC meeting, MIT, April 7 2007 Introduction G from scaling violations of g1(x,Q2) The Bjorken Sum Rule G from charm production

5 GeV  50 GeV/c (e  P) Q2=4 GeV2 2= 0.2 P’ tagging required Exclusivity  Resolution () ≈ 0.3GeV2 without tagging Transverse Imaging

Exclusive charged pion production Assume: 100 days, Luminosity=10E34 Ee=5 GeV Ep=50 GeV Detect the neutron Missing mass reconstruction 10<Q2<15 10<Q2<15 15<Q2<20 15<Q2<20 35<Q2<40 35<Q2<40 Γ dσ/dt (ub/GeV2) Γ dσ/dt (ub/GeV2) 0.01<x<0.02 0.02<x<0.05 0.05<x<0.1 0.05<x<0.1 -t (GeV2) -t (GeV2) Neutron acceptance limits the t-coverage The missing mass method gives full t-coverage for x<0.2 Assume dp/p=1% (pπ<5 GeV)

Transversity and friends Unpol. DF Helicity Transversity q(x) Dq(x) dq(x) Sivers function Boer-Mulders function EIC workshop, May 21th R.Seidl: Transversity measurements at EIC 20

Belle e+ e- Collins data Kretzer FF First successful attempt at a global analysis for the transverse SIDIS and the BELLE Collins data HERMES AUT p data COMPASS AUT d data Belle e+ e- Collins data Kretzer FF  First extraction of transversity (up to a sign) Anselmino et al: hep-ex 0701006 R.Seidl: Transversity measurements at EIC 21 EIC workshop, May 21th 21

What can be expected at EIC? Larger x range measured b y existing experiments COMPASS ends at ~ 0.01, go lower by almost one order of magnitude, but asymmetries become small Have some overlap at intermediate x to test evolution of Collins function and higher twist but at higher Q2 EIC workshop, May 21th R.Seidl: Transversity measurements at EIC 22

The Gluon Contribution to the Nucleon Spin Antje Bruell, Jlab EIC meeting, MIT, April 7 2007 Introduction G from scaling violations of g1(x,Q2) The Bjorken Sum Rule G from charm production

Sivers effect: Kaon electroproduction EIC CLAS12 The low x of EIC makes it ideal place to study the Sivers asymmetry in Kaon production (in particular K-). Combination with CLAS12 data will provide almost complete coverage in x

Correlation between Transverse Spin and Momentum of Quarks in Unpolarized Target All Projected Data Perturbatively Calculable at Large pT Vanish like 1/pT (Yuan) ELIC

Summary eA data from fixed target experiments insufficient to constrain nuclear gluon distribution large kinematic range of EIC will provide precision data on e.g. Q2 dependence of F2A/F2D and x dependence of FLA/FLD and will thus allow to investigate the low x phyiscs of saturation in the nucleus high luminosity and large kinematic coverage will allow to do gluon and quark “tomography” via exclusive processes (measurement of fully differential cross sections for diffractive and non-diffractive channels) single spin asymmetries will determine transverse spin effects and get access to orbital momenta