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Future Research at Jefferson Lab Kees de Jager Jefferson Lab Quarks in Hadrons and Nuclei Erice

Future Research at Jefferson Lab Kees de Jager Jefferson Lab Quarks in Hadrons and Nuclei Erice September 17-23, 2007. Highlights of the 12 GeV Program. Revolutionize Our Knowledge of Spin and Flavor Dependence of PDFS in the Valence Region

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Future Research at Jefferson Lab Kees de Jager Jefferson Lab Quarks in Hadrons and Nuclei Erice

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  1. Future Research at Jefferson Lab Kees de Jager Jefferson Lab Quarks in Hadrons and Nuclei Erice September 17-23, 2007

  2. Highlights of the 12 GeV Program • Revolutionize Our Knowledge of Spin and Flavor Dependence of PDFS in the Valence Region • Totally New View of Hadron (and Nuclear) Structure: GPDs • Determination of the quark angular momentum • Exploration of QCD in the Nonperturbative Regime: • Existence and properties of QCD flux-tube excitations • New Paradigm for Nuclear Physics: Nuclear Structure in Terms of QCD • Spin- and flavor-dependent EMC Effect • Quark propagation through nuclear matter • Precision Tests of the Standard Model • Factor 20 improvement in (2C2u-C2d) axial-vector quark couplings • Determination of sin2w to within 0.00025

  3. 12 GeV : Unambiguous Flavor Structure x —> 1 After 35 years: Miserable Lack of Knowledge of Valence d-Quarks Hall A at 11 GeV with BigBite pQCD di-quark correlations

  4. Unambiguous Resolution of Valence Spin A1p at 11 GeV A1n at 11 GeV

  5. Complements Spin-Flavor Dependence at RHIC At RHIC with W production At JLab with 12 GeV upgrade 12 Stops at x≈0.5 AND needs valence d(x)

  6. Experiments at 11 GeV will extend EMFF data Neutron Proton Electric To 15 GeV2 To 5 GeV2 Magnetic To 15 GeV2

  7. Exclusive 0 production on transverse target 0 A ~ 2Hu + Hd 0 B ~ 2Eu + Ed A~ Hu - Hd B ~ Eu - Ed + AUT Asymmetry depends linearly on the GPDE, which enters Ji’s sum rule K. Goeke, M.V. Polyakov, M. Vanderhaeghen, 2001 xB

  8. Hybrid mesons Hybrid mesons and mass predictions 1 GeV mass difference Normal mesons Jpc = 1-+ Lattice 1-+ 1.9 GeV 2+- 2.1 GeV 0+- 2.3 GeV Lowest mass expected to be 1(1−+) at 1.9±0.2 GeV

  9. Why Photoproduction ? after before q q q q Quark spins aligned q q q q  beam Almost no data in hand in the mass region where we expect to find exotic hybrids when flux tube is excited after before Jpc = 1-+ Quark spins anti-aligned A pion or kaon beam, when scattering occurs, can have its flux tube excited  beam Much data in hand but little evidence for gluonic excitations (and not expected)

  10. Physics goals and key features The physics goal of GlueX is to map the spectrum of hybrid mesons starting with those with the unique signature of exotic JPC • Identifying JPC requires an amplitude analysis which in turn requires • linearly polarized photons • detector with excellent acceptance and resolution • sensitivity to a wide variety of decay modes Final states include photons and charged particles and require particle identification Hermetic detector with large acceptance for charged and neutral particles In addition, sensitivity to hybrid masses up to 2.5 GeV requires 9 GeV photons which will be produced using coherent bremsstrahlung from 12 GeV electrons

  11. Future Possibilities (Purely Leptonic) JLab e2e @ 12 GeV Møller at 11 GeV at JLab sin2W to ± 0.00025! ee ~ 25 TeV reach e.g. Z’ reach ~ 2.5 TeV Higher luminosity and acceptance • Comparable to single Z-pole measurement: shed light on 4 disagreement • Best low-energy measurement until ILC or -Factory • Could be launched ~ 2015 Kurylov, Ramsey-Musolf, Su Does Supersymmetry (SUSY) provide a candidate for dark matter? • Neutralino is stable if baryon (B) and lepton (L) numbers are conserved • In RPV B and L need not be conserved: neutralino decay

  12. PV DIS at 11 GeV with an LD2 target For an isoscalar target like 2H, the structure functions largely cancel in the ratio: (Q2 >> 1 GeV2 , W2 >> 4 GeV2, x ~ 0.3-0.5) • Must measure APV to 0.5% fractional accuracy! • Luminosity and beam quality available at JLab e- e- Z* * X N • 6 GeV experiment will launch PV DIS measurements at JLab (2009) • 11 GeV experiment will allow tight control of systematic errors • Important constraint should LHC observe an anomaly

  13. Precision High-x Physics with PV DIS For hydrogen 1H: 1% APV measurements Longstanding issue: d/u as x1 • Allows d/u measurement on a single proton! Charge Symmetry Violation (CSV) at High x: clean observation possible? Londergan & Thomas • Direct observation of CSV at parton level! • Implications for high-energy collider pdfs • Could explain large portion of the NuTeV anomaly Needs 1% measurement of APV at x ~ 0.75 Global fits allow 3 times larger effects

  14. A Vision for Precision PV DIS Physics • Hydrogen and Deuterium targets • Better than 2% errors (unlikely that any effect is larger than 10%) • x-range 0.25-0.75 • W2 well over 4 GeV2 • Q2 range a factor of 2 for each x (except x~0.75) • Moderate running times • CW 90 µA at 11 GeV • 40 cm liquid H2 and D2 targets • Luminosity > 1038/cm2/s • solid angle > 200 msr • count at 100 kHz • on-line pion rejection of 102 to 103 Goal: Form a collaboration, start real design and simulations, after successful pitch to US community at the ongoing Nuclear Physics Long Range Plan

  15. Summary of Future Research at JLab • The Upgrade to 12 GeV at JLab is well underway (preparing for CD-2 review this month!) with strong support from the Nuclear Physics LRP • It will allow ground-breaking studies of • the structure of the nucleon • exotic mesons and the origin of confinement • the QCD basis of nuclear structure • the Standard Model at the multi-TeV scale • All requiring the use of highly polarized beams (and/or targets) • The schedule of the LQCD program at JLab is commensurate with the physics goals of the 12 GeV Upgrade • Design studies at JLab have led to a promising design of an electron-ion collider (ELIC) • a luminosity of up to ~1035 cm-2 s-1 • at a center-of-mass energy between 20 and 90 GeV • for collisions between polarized electrons/positrons and ions (A≤208)

  16. Upgrade magnets and power supplies CHL-2 Enhance equipment in existing halls Add new hall 12 11 6 GeV CEBAF

  17. Hall B - CLAS12 Forward Calorimeter Preshower Calorimeter Forward Cerenkov (LTCC) Forward Time-of-Flight Detectors Forward Drift Chambers Superconducting Torus Magnet New TOF Layer Inner Cerenkov (HTCC) Central Detector Beamline Instrumentation * Reused detectors from CLAS Inner Calorimeter

  18. Hall C - Side View of SHMS Design

  19. Hall D - Coherent Bremsstrahlung Incoherent & coherent spectrum 40% polarization in peak tagged (0.1% resolution) 12 GeV electron beam flux This technique provides requisite energy, flux and linear polarization photons out collimated electrons in spectrometer (two magnets) diamond crystal photon energy (GeV)

  20. Hall D - GluEx Detector Hermetic detection of charged and neutral particles Tagger Spectrometer (Upstream)

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