From the nucleus to the quarks Roy J

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 Argonne National Laboratory 2

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

Tony’s 1977 letter on pion-deuteron scattering “It [t 20] is a very interesting quantity to measure …” Argonne National Laboratory 4

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

Los Alamos Meson Physics Facility (LAMPF) Series of three pion-deuteron scattering experiments at LAMPF • Exp. 388 (LEP) • Exp. 483 (LEP) • Exp. 673 (P 3) Argonne National Laboratory 6

Issues in Pion-Deuteron Elastic Scattering (ca. 1982) § Pion Absorption § p – Afnan, Thomas, … D § § § p, r d Exact three-body calculations Relativistic Include absorption – – – Dibaryon Resonances? ? p Rinat, Thomas et al. Giraud et al Blankleider and Afnan Betz and Lee and Matsuyama Garcilazo D d 1 D 2, 3 F 3, … Argonne National Laboratory 7

Polarization in Pion-Deuteron Elastic Scattering The LAMPF Experiments First polarization experiments in pion-deuteron scattering 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 Argonne National Laboratory 8

Argonne National Laboratory 1983 9

Pion-Deuteron Scattering Puzzle Blankleider & Afnan Betz & Lee Fayard et al Rinat et al Garcilazo 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 10

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

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, Le. Page, Matveev et al Argonne National Laboratory 12

First t 20 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 13

Polarized Deuterium Gas Target in the VEPP-3 Electron Storage Ring Argonne-Novosibirsk Collaboration 2 Ge. V 200 m. A • 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 14

Polarized Deuterium Gas Target in VEPP-3 Last published T 20 measurement in e-d scattering! D. Nikolenko et al, PRL 90 (2003) Argonne National Laboratory 15

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

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

Two photon exchange in e-p elastic scattering Rosenbluth data Golden mode: positron and electron elastic scattering from the proton Polarization transfer data Three new experiments: • BINP Novosibirsk – 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) 035205 J. Carlson, M. Vanderhaeghen, Annu. Rev. Nucl. Part. Sci. 57 (2007) 171 Argonne National Laboratory Courtesy of W. Melnitchouk • JLab Hall B – LH 2 target, CLAS • DESY (OLYMPUS) - internal target 18

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 19

Fast forward – Jefferson Lab Argonne National Laboratory 20

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

The Neutron Structure Function at high x SU(6) symmetry p. QCD Scalar di-quark Reviews: N. Isgur, PRD 59 (1999), S Brodsky et al NP B 441 (1995), W. Melnitchouk and A. Thomas PL B 377 (1996) 11. Argonne National Laboratory 22

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

Nuclear Physicists’ Approach to F 2 n § 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 24

Ratio of 3 He, 3 H § § Measure F 2’s and form ratios: JLab E 12 -06 -118 I. Afnan et al, PRC 68 (2003) Form “super-ratio”, r, then where § Theoretically, Argonne National Laboratory 25

E 12 -06 -118 Projected Results • JLab E 12 -06 -118, G. Petratos, J. Gomez, R. J. Holt, R. Ransome et al Argonne National Laboratory 26

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 27

Tritium Targets at Electron Accelerators Lab Year Quantity (k. Ci) Thickness (g/cm 2) Current (m. A) Current x thickness (m. A-g/cm 2) Safe FOM (m. Ag/cm 2/k. Ci) Stanford HEPL 1963 25 0. 8 1 0. 8 0. 03 MIT-Bates 1982 180 0. 3 20 6. 0 0. 03 Saclay 1985 10 1. 1 15 16. 0 1. 6 JLab 201? 1. 6 0. 13 30 3. 9 2. 4 JLab also has a huge spectrometer acceptance advantage, eg. SBS Argonne National Laboratory 28

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: 3 H/3 He Happy Birthday Tony! Argonne National Laboratory 29