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From the nucleus to the quarks Roy J. Holt

From the nucleus to the quarks Roy J. Holt. Achievements and Future Directions in Subatomic Physics: A Workshop in honor of Tony Thomas’ 60 th birthday Adelaide 15-19 February 2010. Tony’s perspective (ca. 1977). Happy Birthday!. Courtesy of J. Carlson.

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From the nucleus to the quarks Roy J. Holt

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  1. From the nucleus to the quarksRoy J. Holt Achievements and Future Directions in Subatomic Physics: A Workshop in honor of Tony Thomas’ 60th birthday Adelaide 15-19 February 2010

  2. Tony’s perspective (ca. 1977) Happy Birthday! Courtesy of J. Carlson Argonne National Laboratory

  3. The Deuteron has an Extraordinary Role in Nuclear Physics Subnucleonic Effects Hadronic Probes Standard Model Nucleon-Nucleon Models Neutron Target Argonne National Laboratory

  4. Tony’s 1977 letter on pion-deuteron scattering “It [t20] is a very interesting quantity to measure …” Argonne National Laboratory

  5. Spin 1 nucleus: MS = 1 MS = 0 MS =-1 MS=1, -1 MS=0 Scattering from aligned Deuterons Argonne National Laboratory

  6. Los Alamos Meson Physics Facility (LAMPF) • Series of three pion-deuteron scattering experiments at LAMPF • Exp. 388 (LEP) • Exp. 483 (LEP) • Exp. 673 (P3) Argonne National Laboratory

  7. Pion Absorption Dibaryon Resonances?? Exact three-body calculations Afnan, Thomas,… Relativistic Include absorption Rinat, Thomas et al. Giraud et al Blankleider and Afnan Betz and Lee Lee and Matsuyama Garcilazo p p D p,r d D d 1D2 , 3F3 , … Issues in Pion-Deuteron Elastic Scattering (ca. 1982) Argonne National Laboratory

  8. Polarization in Pion-Deuteron Elastic Scattering The LAMPF Experiments R. J. Holt et al, PRL 43 (1979) 1229 R. J. Holt et al, PRL 47 (1981) 472 E. Ungricht et al, PRL 52 (1984) 333 First polarization experiments in pion-deuteron scattering Argonne National Laboratory

  9. Argonne National Laboratory 1983

  10. Blankleider & Afnan Betz & Lee Fayard et al Rinat et al Garcilazo Pion-Deuteron Scattering Puzzle Jennings & Rinat, NP A (1988) Calculations that don’t include pion absorption agree best with the data!! Confirmed by TRIUMF data: G. Smith et al, PRC 38 (1988) 251. E. Ungricht et al, PRC 31 (1985) 934 Argonne National Laboratory

  11. Measure another quantity: Scatter from aligned deuterons e’ e q=pe-pe’ MS=1, -1 d d’ MS=0 Elastic Scattering from the Deuteron Electron-deuteron scattering Cross section depends on three electromagnetic form factors: Argonne National Laboratory

  12. Issues in Electron-Deuteron Elastic Scattering • Meson-Exchange Models • Wiringa, Schiavilla, et al. • Chung, Coester, Polyzou, Hummel, Tjon, Phillips, Wallace, Gross, van Orden, et al. • QCD Inspired Models • Reduced Nuclear Amplitudes • Brodsky, Chertok, Hiller, Ji • Constituent Counting Rule • Brodsky, Farrar, LePage, Matveev et al Argonne National Laboratory

  13. First t20 Experiment in Electron-Deuteron Scattering First experiment in the South Hall at MIT-Bates M. E. Schulze et al., PRL 52 (1984) Argonne National Laboratory

  14. PolarizedDeuterium Gas Target in the VEPP-3 Electron Storage RingArgonne-Novosibirsk Collaboration 2 GeV 200 mA • First use of a storage cell for polarized gas targets in a storage ring • Proof of principle for HERMES: DESY PRC R. Gilman et al., PRL 65 (1990) 1733 Argonne National Laboratory

  15. Polarized Deuterium Gas Target in VEPP-3 Last published T20 measurement in e-d scattering! D. Nikolenko et al, PRL 90 (2003) Argonne National Laboratory

  16. World’s Data for Electron-Deuteron Scattering Argonne National Laboratory

  17. Technology led to worldwide programs Storage Cells in Storage Rings Neutron and Deuteron Polarimeters Laser-Driven Target NIKHEF LAMPF MIT-Bates SIN/PSI Novosibirsk TRIUMF HERMES at DESY Jefferson Lab IUCF Cooler Argonne Argonne National Laboratory

  18. Two photon exchange in e-p elastic scattering Golden mode:positron and electron elastic scattering from the proton Rosenbluth data Polarization transfer data • Three new experiments: • BINP Novosibirsk – internal target • JLab Hall B – LH2 target, CLAS • DESY (OLYMPUS) - internal target P. G. Blunden et al, PRC 72 (2005) 034612 A.V. Afanasev et al, PRD 72 (2005) 013008 J. Arrington et al, PRC 76 (2007) 035205J. Carlson, M. Vanderhaeghen, Annu. Rev. Nucl. Part. Sci. 57 (2007) 171 Argonne National Laboratory Courtesy of W. Melnitchouk

  19. Very preliminary Novosibirsk data e+-p/e-- p cross section ratio J. Arrington, L. M. Barkov, V. F. Dmitriev, V. V. Gauzshtajn, R. A Golovin, A. V. Gramolinv, R. J. Holt, V. V. Kaminsky, B. A. Lazarenko, S. I . Mishnev, N. Yu. Muchnoi, D. M. Nikolenko, A. V. Osipov, I. A. Rachek, R. Sh. Sadykov, Yu. V. Shestakov, V. N. Stibunov, H. de Vries, S. A. Zevakov, V. N. Zhilich ----- ANL, BINP, INP TPU, NIKHEF Argonne National Laboratory

  20. Fast forward – Jefferson Lab Argonne National Laboratory

  21. hadronic leptonic Deep Inelastic Scattering and Structure Functions • Proton structure function: • Neutron structure function (isospin symmetry): • Ratio: • Nachtmann inequality: • Focus on high x: Parton model: Argonne National Laboratory

  22. The Neutron Structure Function at high x SU(6) symmetry pQCD Scalar di-quark Reviews: N. Isgur, PRD 59 (1999), S Brodsky et al NP B441 (1995), W. Melnitchouk and A. Thomas PL B377 (1996) 11. Argonne National Laboratory

  23. Extractions with modern deuteron wave functions The ratio at high x has a strong dependence on deuteron structure. • Lorentz invariant convolution relation • Light front with null plane kinematics J. Arrington et al, J. Phys. G 36 (2009) Argonne National Laboratory Courtesy of J. Arrington

  24. Nuclear Physicists’ Approach to F2n • Problems: • The proton experiments are difficult and costly. • The deuteron experiments present extraction complications. • Nuclear physicists’ solution: Add another nucleon. I. Afnan et al, PRC 68 (2003) Argonne National Laboratory

  25. Ratio of 3He, 3H JLab E12-06-118 I. Afnan et al, PRC 68 (2003) • Measure F2’s and form ratios: • Form “super-ratio”, r, then where • Theoretically, Argonne National Laboratory

  26. E12-06-118 Projected Results • JLab E12-06-118, G. Petratos, J. Gomez, R. J. Holt, R. Ransome et al Argonne National Laboratory

  27. Tritium target design must pass safety hurdle at JLab Tritium Target Task Force E. J. Beise (U. of Maryland) B. Brajuskovic (Argonne) R. J. Holt (Argonne) W. Korsch (U. of Kentucky) D. Meekins (JLab) T. O’Connor (Argonne) G. G. Petratos (Kent State U.) R. Ransome (Rutgers U.) P. Solvignon (JLab) B. Wojtsekhowski (JLab) Review: June 2010 Argonne National Laboratory

  28. Tritium Targets at Electron Accelerators JLab also has a huge spectrometer acceptance advantage, eg. SBS Argonne National Laboratory

  29. Summary • Tony and colleagues have had a profound influence on experimental nuclear physics. • Pion- and electron-deuteron scattering drove polarization technology. • Development of the polarization technology has been extraordinarily fruitful – HERMES, MIT-Bates, Novosibirsk, NIKHEF, JLab, ... • Latest internal target experiment: best evidence for 2-photon exchange • Scientific stage being set at JLab for d/u ratio measurement using polarization in isospin space: 3H/3He Happy Birthday Tony! Argonne National Laboratory

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