Hadron Physics in America L. Cardman

Venues for Hadronic Physics Today (and their near-term plans) Two Major Facilities: Jefferson Lab (~6 GeV, cw, polarized electron beams) RHIC BNL (up to 250 GeV polarized protons on polarized protons and heavy ions) A broad variety of experiments at facilities focused on other physics (e.g. EDM of neutron at LANSCE and Drell-Yan at FNAL) and at smaller facilities (e.g. HI  S at TUNL) Participation in many experiments at facilities overseas (e.g. Hermes)

Jefferson Lab A 4 GeV (now 5.7 GeV), high intensity, cw electron accelerator built to investigate the structure of nucleons and nuclei The approved research program includes 167 experiments on a broad variety of topics Research operations began 10/95 ­ in full operation for 7½ years (since 11/97) ­ data for 118 full experiments and parts of 10 more are complete ­ results are emerging regularly in the published literature

Linac Arc 3 End Stations

Hall A: Two High Resolution (10 -4 ) Spectrometers

Hall B: The CEBAF Large Acceptance Spectrometer (CLAS)

Hall C: A High Momentum and a Broad Range Spectrometer Setup Space for Unique Experiments

JLab Scientific “Campaigns” The Structure of the Nuclear Building Blocks 1.How are the nucleons made from quarks and gluons? 2.What are the mechanism of confinement and the dynamics of QCD? 3.How does the NN Force arise from the underlying quark and gluon structure of hadronic matter? The Structure of Nuclei 4.What is the structure of nuclear matter? 5.At what distance and energy scale does the underlying quark and gluon structure of nuclear matter become evident? Symmetry Tests in Nuclear Physics 6.Is the “Standard Model” complete? What are the values of its free parameters?

Enhanced Figure of Merit for Experiments Requiring Polarized Beam

Near Term Plans Complete energy increase of base accelerator from the original 4.0 GeV design to today’s 5.7 GeV to 6.0 GeV (~1/07) Complete development of high intensity (up to 200  A) polarized beams with mid-term goal of >85% polarization and enhanced helicity correlated characteristics as driven by the approved program: CharacteristicAchievedGoal position stability (nm)2-3 1 intensity stability (ppm) Continue to run the physics program outlined briefly above

RHIC Spin

RHIC Spin Physics Program  0,+,- Production Heavy Flavors Prompt Photon Gluon Polarization Flavor Decompsition Transverse single/double spin physics W physics Longitudinal single spin physics Transversity: Sivers vs. Collins effects & physics of higher twists; Pion interf. Fragmentation Transverse single spin physics Phenix-Local Polarimetry

RHIC Spin Future Plans For next four years Upgrade Plans Include: Factor of six enhancement of luminosity Operation at sqrt(s) = 500 GeV Luminosity Goals are: p  – p  60 x cm -2 s -1 ; 70% polarization (100 GeV) 150 x cm -2 s -1 ; 70% polarization (100 GeV) (luminosity averaged over store delivered to 2 IRs) Note: w/ electron cooling might reach as high as 5 x cm -2 s -1

Timeline for the Baseline RHIC Spin Program Ongoing progress on p+p luminosity, pol’n in uncharted territory:  ~1 more order of magnitude needed in L, factor ~1.5 in P  Orderly plan for needed improvements in place     Substantial running time needed: ~70 weeks overall  First phase of program uses existing detector:  s=200 GeV with present detectors for gluon pol’n (  g) at higher x & transverse asymmetries aaab

High Intensity  -Source at Duke Broad physics program planned for HI  S ­ Nuclear Astrophysics ­ Few Body Physics ­ GDH Sum rule for deuterium ­ Nuclear Structure studies using NRF ­ Compton scattering from nucleons and few body nuclei ­ Pion Threshold studies Commissioning of fully upgraded accelerator: Summer 2006 Nuclear Physics Program begins Fall 2006: Dec. 06 – March 07 Linear Pol.- Below 50 MeV, >10 8  /s Sept. 07 – Dec. 07 Circ. Pol. Up to 95 MeV, >10 8  /s

E906 at FNAL (d/u for the proton) Anticipated start FY09 Relative to E866/NuSea: Cross section scales as 1/s ­ 7  that of 800 GeV beam Backgrounds, primarily from J/  decays scale as s ­ 7  Luminosity for same detector rate as 800 GeV beam 50  statistics!!

Mid-Term Prospects (to ~2012) Continued Operation of and RHIC Spin) Experiments like FNAL and the HI  S program Enhancements of RHIC Spin Construction of the JLab 12 GeV Upgrade

Timeline for the Baseline RHIC Spin Program Ongoing progress on p+p luminosity, pol’n in uncharted territory:  ~1 more order of magnitude needed in L, factor ~1.5 in P  Orderly plan for needed improvements in place     Substantial running time needed: ~70 weeks overall  Program divides into 2 phases:  s=200 GeV with present detectors for gluon pol’n (  g) at higher x & transverse asymmetries;  s=500 GeV with detector upgrades for  g at lower x & W prod’n

The JLab 12 GeV Upgrade Major Programs in Four Areas: The experimental study of the confinement of quarks – one of the outstanding questions of the 21 st century physics Dramatic improvements in our knowledge of the fundamental quark- gluon structure of the nuclear building blocks Further exploration of the limits of our understanding of nuclei in terms of nucleons and the N-N force Precision experiments with sensitivity to TeV scale physics beyond the Standard Model And other science we can’t foresee

CHL-2 Upgrade magnets and power supplies Enhance equipment in existing halls 6 GeV CEBAF Add new hall

Enhanced Equipment in Halls A, B, & C and a New Hall D 9 GeV tagged polarized photons and a 4  hermetic detector D Super High Momentum Spectrometer (SHMS) at high luminosity and forward angles C CLAS upgraded to higher (10 35 ) luminosity and coverage B High Resolution Spectrometer (HRS) Pair, and specialized large installation experiments A

12 GeV Upgrade: Project Schedule Conceptual Design (CDR) Research and Development (R&D) 2006 Advanced Conceptual Design (ACD) Project Engineering & Design (PED) Long Lead Procurement Construction Pre-Ops (beam commissioning) Critical Decision (CD)Presented at IPR CD-0 Mission Need2QFY04 (Actual) CD-1 Preliminary Baseline Range4QFY05 CD-2A/3A Construction and Performance Baseline of Long Lead Items 2QFY07 CD-2B Performance Baseline4QFY07 CD-3B Start of Construction3QFY08 CD-4 Start of Operations1QFY13

Progress Toward 12 GeV CD-0 in March 2004 DOE Science Review (April 2005) ­ Formal DOE review, “Certified” the Science case for the Upgrade “The overall proposed program represents an impressive coherent framework of research directed towards one of the top frontiers of contemporary science: the exploration of confinement, a unique phenomenon of the strong Interaction, one of the four fundamental forces of nature.” “…these experimental studies are challenging, but feasible with the proposed upgrade,… they are essential to advance our theoretical understainding of confinement and the structure of hadrons and nuclei,… and they have a high probability for discoveries leading to significant paradigm shifts.” the upgrade “also provides a unique opportunity to use the electroweak interaction to search for physics beyond the Standard Model” DOE “CD-1” Review (July 2005) ­ Formally in preparation for DOE Critical Decision CD-1, which defines the Preliminary Baseline Range ­ Passed with flying colors: No action items; all CD-1 prerequisites certified as “met” Awaiting Formal CD-1 ­ Expect this Fall

Longer Term Prospects (2013 and Beyond) Operation of the GeV Continuation of RHIC Spin Plans developing now for a new electon-ion collider that would be constructed during this period, focused on the next generation of DIS and DES experiments There are two competing designs: ­ ELIC (JLab) ­ eRHIC (BNL)

Science Motivating the Next Generation Collider How do quarks and gluons provide the binding and spin of the nucleons? What is the quark-gluon structure of mesons? How do quarks and gluons evolve into hadrons? How does energy convert to mass? How does nuclear binding originate from quarks and gluons? How do gluons behave in nuclei? ……..

ELIC/eRHIC Complementary to the Physics of the 12 GeV Upgrade g 12 GeV will access the valence quark regime (x > 0.3), where the quark properties are not masked by the sea quarks and glue 12 GeV The Collider will focus on the low-x regime (x<0.1), where the glue dominates (and eventually saturates) Collider g

A Draft Experimental Program for the Next-Generation Electron-Ion Collider Nucleon structure, role of quarks and gluons in the nucleons ­ Un-polarized quark and gluon distributions, confinement in nucleons ­ Polarized quark and gluon distributions (LOWEST POSSIBLE X) ­ Correlations between partons Exclusive processes--> Generalized Parton Distributions ­ Understanding confinement with low x/lowQ 2 measurements Meson Structure: ­ Goldstone bosons and play a fundamental role in QCD Nuclear Structure, role of partons in nuclei ­ Confinement in nuclei through comparison e-p/e-A scattering Hadronization in nucleons and nuclei & effect of nuclear media ­ How do knocked off partons evolve in to colorless hadrons Partonic matter under extreme conditions ­ For various A, compare e-p/e-A

Ion Linac and pre - booster IR Beam Dump Snake CEBAF with Energy Recovery 3-7 GeVelectrons GeV light ions Solenoid Ion Linac and pre - booster IR Beam Dump Snake CEBAF with Energy Recovery 3-7 GeVelectrons GeV light ions Solenoid Ion Linac and pre - booster IR Beam Dump Snake CEBAF with Energy Recovery 3 -7 GeVelectrons GeV light ions Solenoid Electron Injector Electron Cooling ELIC Layout

The same electron accelerator can also provide 25 GeV electrons for fixed target experiments for physics JLab)  Implement 5-pass recirculator, at 5 GeV/pass, as in present CEBAF (One accelerating & one decelerating pass through CEBAF  GeV CM Collider Program)  Exploring whether collider and fixed target modes can run simultaneously

eRHIC – Two Possible Machine Designs

Ring-Linac Design (1)

Ring-Linac Design (2)

Luminosity vs. CM Energy TESLA-N ELIC-JLab ELIC at Jlab ­ 3-7 GeV e - on GeV p (both polarized) ­ GeV CM Energy ­ Polarized light ions ­ Luminosity as high as 0.8x10 35 cm -2 sec -1 luminosity eRHIC at BNL ­ 5-10 GeV e - on GeV p (both polarized) ­ GeV CM Energy ­ Polarized light ions ­ Heavy ion beams available ­ Luminosity from to perhaps as high as cm -2 sec -1 (depending on design choice) eRHIC - BNL

Conclusion: A Fascinating Time for Hadronic Physics Tremendous activity today (w/ CEBAF and RHIC Spin and many other projects) within the hadronic physics community in America Major enhancements in our capabilities are in progress: ­ JLab Upgrade to 12 GeV ­ RHIC Spin luminosity and detectors ­ Experiments like E906 at FNAL ­ HI  S ­ ……. Advanced planning for the longer term: ­ JLab or BNL