R.G. Milner 2nd EIC Workshop

Summary and Outlook

• science case

• machine design

• EIC realization

R.G. Milner 2nd EIC Workshop

Why EIC?Because it is essential for the study of the fundamental structure of matter beyond 2010 to understand nucleon and nuclei and to test QCDContext: • particle physics search for `God particle’ • astrophysical speculation on dark matter and energy

On the timescale of EIC we expect full ab initio QCD calculations of many experimental observables

R.G. Milner 2nd EIC Workshop

What will we learn from EIC?

• Spin structure of the nucleon - gp

1(x) at low x dramatic QCD prediction - gluon and sea quark polarization - Bjorken sum rule QCD test - new (GPD, transversity) parton distributions• Partonic understanding of nuclei hot QCD - gluon momentum distribution in nuclei - fundamental explanation of nuclear binding - saturation

R.G. Milner 2nd EIC Workshop

Machine Design• Mainline machine design reaches luminosity

~ 1033 nucleons cm-2 s-1

ring-ring eRHIC design• Realistic (but aggressive) design based on RHIC and B factory performance• High luminosity requires electron cooling• Cost framework understood ~ 300 – 500 M$• Other concepts (eRHIC linac-ring, ELIC)

should be vigorously pursued to determine realistic designs

R.G. Milner 2nd EIC Workshop

Luminosity• At any luminosity there will be

measurements which are statistically marginal

• There is a substantial and excellent part of EIC case realizable without electron cooling of ion beam

spin structure of nucleon partonic understanding of nuclei• It is reasonable to consider scenarios where

EIC gets underway without electron cooling and the path to full luminosity is staged in time

R.G. Milner 2nd EIC Workshop

Realization of EIC• 2001 Long Range Plan (LRP) endorsed

science favorably and recommended support for R&D

• Anticipate next LRP to begin in 2005• Wish to present science case and

machine design at upcoming LRP with goal of receiving high priority for new construction of a high luminosity electron ion collider

R.G. Milner 2nd EIC Workshop

Issues• Maintain and enhance community wide and

international support• Focus and sharpen scientific case• Continue to develop machine designs and

options• Several meetings planned for later this year - eRHIC ZDR review ~ May 2004 - workshops on GPDs, saturation ~ late

summer - meeting to organize final preparation for LRP ~ early 2005

R.G. Milner 2nd EIC Workshop

EIC Steering Committee• A. Caldwell (MPI Munich)• A. Deshpande (StonyBrook)• R. Ent (JLab)• G. Garvey (LANL)• R. Holt (ANL)• E. Hughes (Caltech)• K.-C. Imai (Kyoto Univ.)• R. Milner (MIT)• P. Paul (BNL)• J.-C. Peng (Illinois)• S. Vigdor (Indiana Univ.)

R.G. Milner 2nd EIC Workshop

Summary• 2nd EIC workshop at JLab an outstanding

success• Clear and substantial progress since 1st EIC

workshop at BNL• Science case for EIC becomes more

compelling• Solid machine design for luminosity of ~ 1033

nucleon cm-2 s-1 together with more futuristic concepts having potential for increased luminosity

• Essential over next year to prepare for aggressive engagement in the upcoming Long Range Planning Exercise