Roy Holt

23 May 2008

With apologies for being incomplete

Summary and Outlook

EIC White Papers 2007 – an astounding year

The Electron Ion Collider (EIC) White Paper

The GPD/DVCS White Paper Position Paper: e+A Physics at an

Electron Ion Collider The eRHIC machine: Accelerator

Position Paper ELIC Zero’th Order Design Report

Available at:• NSAC LRP2007 home page• Rutgers Town Meeting page• http://www.bnl.gov/eic

The EIC Working Group

17C. Aidala, 28E. Aschenauer, 10J. Annand, 1J. Arrington, 26R. Averbeck, 3M. Baker, 26K. Boyle, 28W. Brooks, 28A. Bruell, 19A. Caldwell, 28J.P. Chen, 2R. Choudhury, 10E. Christy, 8B. Cole, 4D. De Florian, 3R. Debbe, 26,24-1A. Deshpande*, 18K. Dow, 26A. Drees, 3J. Dunlop, 2D. Dutta, 7F. Ellinghaus, 28R. Ent, 18R. Fatemi, 18W. Franklin, 28D. Gaskell, 16G. Garvey, 12,24-1M. Grosse-Perdekamp, 1K. Hafidi, 18D. Hasell, 26T. Hemmick, 1R. Holt, 8E. Hughes, 22C. Hyde-Wright, 5G. Igo, 14K. Imai, 10D. Ireland, 26B. Jacak, 15P. Jacobs, 28M. Jones, 10R. Kaiser, 17D. Kawall, 11C. Keppel, 7E. Kinney, 18M. Kohl, 9H. Kowalski, 17K. Kumar, 2V. Kumar, 21G. Kyle, 13J. Lajoie, 16M. Leitch, 27A. Levy, 27J. Lichtenstadt, 10K. Livingstone, 20W. Lorenzon, 145. Matis, 12N. Makins, 6G. Mallot, 18M. Miller, 18R. Milner*, 2A. Mohanty, 3D. Morrison, 26Y. Ning, 15G. Odyniec, 13C. Ogilvie, 2L. Pant, 26V. Pantuyev, 21S. Pate, 26P. Paul, 12J.-C. Peng, 18R. Redwine, 1P. Reimer, 15H.-G. Ritter, 10G. Rosner, 25A. Sandacz, 7J. Seele,

12R. Seidl, 10B. Seitz, 2P. Shukla, 15E. Sichtermann, 18F. Simon, 3P. Sorensen, 3P. Steinberg, 24M. Stratmann, 22M. Strikman, 18B. Surrow, 18E. Tsentalovich, 11V. Tvaskis, 3T. Ullrich, 3R. Venugopalan, 3W. Vogelsang, 28C. Weiss, 15H. Wieman,15N. Xu,3Z. Xu, 8W. Zajc.

1Argonne National Laboratory, Argonne, IL; 2Bhabha Atomic Research Centre, Mumbai, India; 3Brookhaven National Laboratory, Upton, NY; 4University of Buenos Aires, Argentina; 5University of California, Los Angeles, CA; 6CERN, Geneva, Switzerland; 7University of Colorado, Boulder,CO; 8Columbia University, New York, NY; 9DESY, Hamburg, Germany; 10University of Glasgow, Scotland, United Kingdom; 11Hampton University, Hampton, VA; 12University of Illinois, Urbana-Champaign, IL; 13Iowa State University, Ames, IA; 14University of Kyoto, Japan; 15Lawrence Berkeley National Laboratory, Berkeley, CA; 16Los Alamos National Laboratory, Los Alamos, NM; 17University of Massachusetts, Amherst, MA; 18MIT, Cambridge, MA; 19Max Planck Institüt für Physik, Munich, Germany; 20University of Michigan Ann Arbor, MI; 21New Mexico State University, Las Cruces, NM; 22Old Dominion University, Norfolk, VA; 23Penn State University, PA; 24RIKEN, Wako, Japan; 24-1RIKEN-BNL Research Center, BNL, Upton, NY; 25Soltan Institute for Nuclear Studies, Warsaw, Poland; 26SUNY, Stony Brook, NY; 27Tel Aviv University, Israel; 28Thomas Jefferson National Accelerator Facility, Newport News, VA

-95 Scientists, 28 Institutions, 9 countries

*Contact People

NSAC 2007 Long Range Plan

“An Electron-Ion Collider (EIC) with polarized beams has been embraced by the U.S. nuclear science community as embodying the vision for reaching the next QCD frontier. EIC would provide unique capabilities for the study of QCD well beyond those available at existing facilities worldwide and complementary to those planned for the next generation of accelerators in Europe and Asia. In support of this new direction:

We recommend the allocation of resources to develop accelerator and detector technology necessary to lay the foundation for a polarized Electron Ion Collider. The EIC would explore the new QCD frontier of strong color fields in nuclei and precisely image the gluons in the proton.”

Introduction

Profound issues in nuclear physics– Structure of visible matter– Role of gluons in hadronic matter– Fundamental symmetries

New facilities on the horizon Concluding statement

The EIC will explore the most compelling issues in nuclear science and technology.

Explore the structure of visible matter

What is the internal landscape of the hadron? – Benchmark: Spatial, spin, flavor and gluonic

structure What is the nature of the nuclear force that binds

protons and neutrons into nuclei?– Frontier: QCD properties of nuclear force– Mysteries: QCD effects in nuclei

“If, in some cataclysm, all of scientific knowledge were to be destroyed, and only one sentence passed on to the next generation, what statement would contain the most information in the fewest words? I believe it is the atomic hypothesis, that all things are made of atoms -- little particles that move around in perpetual motion, attracting each other when they are a little distance apart, but repelling upon being squeezed into one another. In that one sentence, there is an enormous amount of information about the world, if just a little imagination and thinking are applied.” - R. Feynman

Explore the structure of the nucleonExplore the structure of the nucleon

• Parton distribution functions• Longitudinal and transverse spin

distribution functions• Generalized parton distributions•Transverse momentum distributions

A. ThomasE. KinneyF. Yuan,D. Hasch,J. NegeleA. SidorovR. Sassot+ e-p working group talks

Lattice -> quantitative predictions

Explore the structure of the nucleon (continued) – Light quark structure – chiral properties

Neutron structure function – JLab

C. Keppel et alRHIC-Spin region

Spectator forward tagging to minimize deuteron structure –similar requirementsas exclusive, DVCS, diffraction:T. Horn, D. Hasch, M. Derrick, C. Hyde Charge symmetry? A. Thomas

Explore the structure of the nucleon (continued) – strange quark distributions

A. Thomas:Strange quark distribution - HERMES

J. Owens ” more kinematic reach”-> EIC

What about charm quark distribution? A. Deshpande

Data on same time scale as disconnected diagrams in lattice calculations.

Generalized Parton Distributions

Q2

t ),,( txH Bjx~Bjxx

Bjx~

x x

form factors )(),,( 1 tFtxHdxe q

q q PDFs

)()0,0,(, xqxH gq )()0,0,(

~ , xqxH gq …

D. Hasch

GPD’s provide a 2D spatial image as a function of x

C. Weiss

eg, choose meson:sensitive to non-singlet or gluons

Consider “Dirac” GPD: H(x,t)

Lattice – J. NegeleGPD moments

Generalized Parton Distributions

Well documented case,Progress on detector constraints- C. Hyde

Luminosity hungry

Positrons useful

D. Hasch

EIC Kinematic Reach

1 10 100 CM energy (GeV)

101

102

Lu

min

osit

y(*

103

0/c

m2

/s)

103

104

105

109

106

108

107

107

JLab

JLab@12GeV

HERMESCOMPASS

HERA-collider

ELIC

eRHIC

27 G

eV

com

pass

herm

es JLab (upgraded)

JLab@6GeV

EIC

HERA

H. Avakian

D. Hasch

Explore the structure of the nucleon (continued)Transverse Momentum Distributions

H. Avakian – “Welcome to the exciting world of 3D parton distributions.”– Transversity, Sivers, pretzelosity, Boer Mulders, …

A. Bachetta “EIC, a precision machine for TMD’s” “Proof of principle” - R. Seidl - measure transversity, Collins

fragmentation function, determine tensor charge

HERMES + Belle

Prohudin - DIS 2008

QCD and the Origin of Mass

99% of the proton’s mass/energy is due to the self-generating gluon field

–Higgs mechanism has almost no role.

The similarity of mass between the proton and neutron arises from the fact that the gluon dynamics are the same

–Quarks contribute almost nothing.

Explore gluon-dominated matterExplore gluon-dominated matter

EIC: most precise measure of gluon densities

What is the role of gluons and gluon self-interactions in nucleons and nuclei? NSAC-2007

– Gluon dominance in the proton

Gluon distribution G(x,Q2)

• Scaling violation in F2: F2/lnQ2

• FL ~ s G(x,Q2)

• inelastic vector meson production (e.g. J/)

• diffractive vector meson production ~ [G(x,Q2)]2

• …

H. Kowaski, M. Derrick

Recent progress – direct FL measurements from HERA

),(2

),(2

14 2

22

2

2

4

2

2

2

QxFy

QxFy

yxQdxdQ

dL

eXep

T. Ullrich EIC – an FL factory

Projected data on g/g with an EIC, via + p D0 + X

K- + +

RHIC-Spin

The Gluon Contribution to the Proton Spin

Advantage: measurements directly at fixed Q2 ~ 10 GeV2 scale!

g/g

Explore gluon-dominated matterExplore gluon-dominated matter

At high gluon density, gluon recombination should compete with gluon splitting density saturation.

What is the role of gluons and gluon self-interactions in nucleons and nuclei? NSAC-2007

– The nucleus as a “gluon amplifier”

Color glass condensate

Oomph factor stands up under scrutiny.Nuclei greatly extend x reach:xEIC = xHERA/18 for 10+100 GeV, Au

T. Ullrich, R. Venugopalan,e-A Working Group talks

Explore the low energy precision frontier

What are the unseen forces present at the dawn of the Universe but have disappeared from view as the universe evolved? precision electroweak experiments: sin2W , …

Questions for the Universe, Quantum Universe, HEPAP, 2004; NSAC Long Range Plan, 2007

“The task of the physicist is to see through the appearances down to the underlying, very simple, symmetric reality.”

- S. Weinberg

The LHC is driving global interest in low energy tests of the Standard Model.

Relatively high x -> charge symmetry violation?

Preliminary - EIC

What new facilities are essential to this quest?

eRHIC

“We recommend the allocation of resources to develop accelerator and detector technology necessary to lay the foundation for a polarized Electron-Ion Collider.”

NSAC LRP 2007

ELIC

V. PtitsyV. Litvinenko

Polarization:M. BaiE. TsentalovichD. BarberW. Lorenzon

G. Krafft

Crab cavities:M. Masuzawa

Cooling:S. DerbenevV. LitvinenkoF. Wang

R. Milner

Nanofabricated Superconducting RF Composites

Many of the failure modes of SCRF structures can be traced to defects in the Nb surface.

Atomic Layer Deposition is a chemical process capable of coating large and arbitrary shapes.

Vortices in superconductors move in AC fields – RF losses

Vortices are not stable in thin layers Began tests of coated cavities at JLab Prospects excellent for achieving >50 MV/m

M. Pellin, J. Elam, J. Moore, J. Norem, T. Proslier, R. Rimmer, J. Zasadzinski (ANL, IIT, FNAL, JLab)

An application of our technology

Hampton University Proton Therapy Institute – online in 2010

Cynthia Keppel – Scientific and Technical Director

World Community in 2015 and Beyond

Three new major facilities investigating nuclear physics at hadronic level (QCD): GSI, J-PARC and 12-GeV JLab

Two new facilities that explore nuclei at the partonic level: RHIC with upgrades and LHC

Two new proposed facilities that can take our field to the next level: EIC, Project X (FNAL)

Petascale computing facilities are imminent, Exascale is on the way. Outstanding opportunities for the future

The International Picture

NuPECC activities– EIC study group approved at the meeting in

Bucharest on 10/27/2007 with G. Rosner, chair– Charge is to produce a report outlining:

• The science possibilities• The interest among European groups• Possible links with proposals outside Europe

Glasgow meeting in Fall 2008.

The International Picture (continued)

OECD (Organization for Economic Co-operation and Development) Global Science Forum

– Nuclear Physics Working Group- report on ‘optimal evolution of Nuclear Physics at an international level during the next 10-15 years’

Membership – 14 countries Two projects may be ‘Global’ due to size

– EURISOL

– EIC

F. Willeke, S. Chattopadhyay

Columbus’ vision

Look! Purple mountains! Spacious skies! Fruited plains! …Is someone writing this down? - adapted from G. Larson

Yes! white papers, NSAC LRP 2007, but we

need an even more compelling case by next NP LRP (2012-13)

Concluding Statement

EIC research can penetrate some of the most profound mysteries and questions of 21st century physics.

Technology is improving at an astounding rate:

– Accelerator design, cavity improvement, energy recovery,

crab cavities, cooling, polarization, polarimetry, detectors,

petascale computing, …

There are interesting new opportunities worldwide. The next 10 years will be even more exciting than the last 10 years.

We must put forward a most compelling case for the EIC on the time scale of the next LRP.

Summary

Fourth EIC workshop has been a resounding success.

Clear and substantial progress was demonstrated since the last EIC workshop.

Essential to lay the foundation for the next Long Range

Planning Exercise.must develop a clear path forward.

Next Workshop - Berkeley - December 11-13, 2008 Peter Jacobs

Many thanks to

International Advisory Committee Jochen Bartels (DESY) Allen Caldwell (MPI, Munich) Albert De Roeck (CERN) Walter Henning (ANL) Dave Hertzog (UIUC) Xiangdong Ji (U. Maryland) Robert Klanner (U. Hamburg) Katsunobu Oide (KEK) Naohito Saito (KEK) Uli Wienands (SLAC)

Steering Committee•Abhay Deshpande, Stony Brook, RBRC (Co-Chair/Contact person) •Rolf Ent, Jlab •Charles Hyde, ODU/UBP, France •Peter Jacobs, LBL •Richard Milner, MIT (Co-Chair/Contact person) •Thomas Ulrich, BNL •Raju Venugopalan, BNL •Antje Bruell, Jlab •Werner Vogelsang, BNL

Working Groups and Convenors•ep Physics

•Antje Bruell, JLAB •Ernst Sichterman, LBL •Werner Vogelsang, BNL •Christian Weiss, JLAB

•eA Physics •Vadim Guzey, JLAB •Dave Morrison, BNL •Thomas Ullrich, BNL •Raju Venugopalan, BNL

•Detector •Elke Aschenauer, JLAB •Edward Kinney, Colorado •Bernd Surrow, MIT

•Electron Beam Polarimetry •Wolfgang Lorenzon, Michigan

Many thanks to

Workshop Organizing Committee:

Alberto Accardi - Hampton/JLab Andrei Afanasev - Hampton/JLab Eric Christy - Hampton Abhay Deshpande - Stony Brook/RBRC Rolf Ent - JLab/Hampton Cynthia Keppel - Hampton/JLab Lia Merminga - JLab Richard Milner - MIT Thomas Roser - BNL