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 60th birthdayAdelaide15-19 February 2010

Argonne National Laboratory

Tonys perspective (ca. 1977)Courtesy of J. CarlsonHappy Birthday!


Nucleon-Nucleon ModelsHadronic ProbesNeutron TargetSubnucleonic EffectsStandard ModelThe Deuteron has an Extraordinary Role in Nuclear Physics


Tonys 1977 letter on pion-deuteron scatteringIt [t20] is a very interesting quantity to measure


Scattering from aligned Deuterons


Los Alamos Meson Physics Facility (LAMPF)Series of three pion-deuteron scattering experiments at LAMPF

Exp. 388 (LEP)Exp. 483 (LEP)Exp. 673 (P3)


Issues in Pion-Deuteron Elastic Scattering (ca. 1982)Pion Absorption

Dibaryon Resonances??

Exact three-body calculationsAfnan, Thomas,RelativisticInclude absorptionRinat, Thomas et al.Giraud et alBlankleider and AfnanBetz and LeeLee and MatsuyamaGarcilazo


Polarization in Pion-Deuteron Elastic ScatteringR. J. Holt et al, PRL 43 (1979) 1229R. J. Holt et al, PRL 47 (1981) 472E. Ungricht et al, PRL 52 (1984) 333 The LAMPF ExperimentsFirst polarization experiments in pion-deuteron scattering


1983


Pion-Deuteron Scattering PuzzleE. Ungricht et al, PRC 31 (1985) 934

Calculations that dont include pion absorption agree best with the data!!

Confirmed by TRIUMF data: G. Smith et al, PRC 38 (1988) 251.Jennings & Rinat, NP A (1988)


Elastic Scattering from the DeuteronCross section depends on three electromagnetic form factors:Electron-deuteron scattering


Issues in Electron-Deuteron Elastic ScatteringMeson-Exchange ModelsWiringa, Schiavilla, et al.Chung, Coester, Polyzou, Hummel, Tjon, Phillips, Wallace, Gross, van Orden, et al.

QCD Inspired ModelsReduced Nuclear AmplitudesBrodsky, Chertok, Hiller, JiConstituent Counting RuleBrodsky, Farrar, LePage, Matveev et al


First t20 Experiment in Electron-Deuteron ScatteringM. E. Schulze et al., PRL 52 (1984)First experiment in the South Hall at MIT-Bates


Polarized Deuterium Gas Target in the VEPP-3 Electron Storage RingArgonne-Novosibirsk CollaborationR. Gilman et al., PRL 65 (1990) 1733 First use of a storage cell for polarized gas targets in a storage ring Proof of principle for HERMES: DESY PRC 2 GeV200 mA


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


Worlds Data for Electron-Deuteron Scattering


Technology led to worldwide programsNeutron andDeuteronPolarimetersStorage Cells in Storage RingsLaser-Driven TargetNovosibirskHERMES at DESYMIT-BatesIUCF CoolerLAMPFSIN/PSITRIUMFJefferson LabNIKHEFArgonne


Two photon exchange in e-p elastic scatteringP. G. Blunden et al, PRC 72 (2005) 034612A.V. Afanasev et al, PRD 72 (2005) 013008J. Arrington et al, PRC 76 (2007) 035205 J. Carlson, M. Vanderhaeghen, Annu. Rev. Nucl. Part. Sci. 57 (2007) 171

Golden mode: positron and electron elastic scattering from the protonRosenbluth dataPolarization transfer dataCourtesy of W. MelnitchoukThree new experiments:

BINP Novosibirsk internal target

JLab Hall B LH2 target, CLAS

DESY (OLYMPUS) - internal target


Very preliminary Novosibirsk datae+-p/e-- p cross section ratioJ. 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


Fast forward Jefferson Lab


Deep Inelastic Scattering and Structure FunctionsProton structure function:

Neutron structure function (isospin symmetry):

Ratio:

Nachtmann inequality:

Focus on high x:

Parton model:


The Neutron Structure Function at high xSU(6) symmetrypQCDScalar di-quarkReviews: N. Isgur, PRD 59 (1999), S Brodsky et al NP B441 (1995),W. Melnitchouk and A. Thomas PL B377 (1996) 11.


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


Nuclear Physicists Approach to F2nProblems: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)


Ratio of 3He, 3H JLab E12-06-118Measure F2s and form ratios:

Form super-ratio, r, then

where

Theoretically,

I. Afnan et al, PRC 68 (2003)


E12-06-118 Projected Results

JLab E12-06-118, G. Petratos, J. Gomez, R. J. Holt, R. Ransome et al


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. OConnor (Argonne)G. G. Petratos (Kent State U.) R. Ransome (Rutgers U.) P. Solvignon (JLab) B. Wojtsekhowski (JLab)

Review: June 2010


Tritium Targets at Electron AcceleratorsJLab also has a huge spectrometer acceptance advantage, eg. SBS


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 exchangeScientific stage being set at JLab for d/u ratio measurement using polarization in isospin space: 3H/3HeHappy Birthday Tony!


From the nucleus to the quarks Roy J. Holt

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