New quark distributions and semi-inclusive electroproduction on polarized nucleons

Yerevan Physics Institute, Alikhanian Brothers St. 2, AM-375036 Yerevan, Armenia
Nuclear Physics B (Impact Factor: 3.95). 05/1995; DOI: 10.1016/0550-3213(95)00098-D
Source: arXiv

ABSTRACT The quark-parton model calculation including the effects of intrinsic transverse momentum and of all six twist-two distribution functions of quarks in polarized nucleons is performed. It is demonstrated that new twist-two quark distribution functions and polarized quark fragmentation functions can be investigated in semi-inclusive DIS at leading order in Q2. The general expression for the cross-section of semi-inclusive DIS of polarized leptons on polarized nucleons in terms of structure functions is also discussed.

  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: In the semi-inclusive deep inelastic scattering of polarized leptons on a transversely polarized target eight target transverse spin-dependent azimuthal modulations are allowed. In the QCD parton model half of these asymmetries can be interpreted within the leading order approach and the other four are twist-three contributions. The first two leading twist asymmetries extracted by HERMES and COMPASS experiments are related: one to the transversity distribution and the Collins effect, the other to the Sivers distribution function. These results triggered a lot of interest in the past few years and allowed the first extractions of the transversity and the Sivers distribution functions of nucleon. The remaining six asymmetries were obtained by the COMPASS experiment using a 160 GeV/c longitudinally polarized muon beam and transversely polarized deuteron and proton targets. Here we review preliminary results from COMPASS proton data of 2007.
    Journal of Physics Conference Series 05/2011; 295(1):2046-.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The first probe the correlation of the T-odd one-particle fragmentation function which is responsible for the left-right asymmetry of fragmentation of transversely polarized quark and antiquark is done using the 1991–1995 DELPHI data for Z → 2 jet decay. Being integrated over the fraction of longitudinal and over transverse momentum, this correlation is of 2.5ppm order, that means order of 7% for the analyzing power. This gives a hope to use certain effects in polarized DIS experiments for transversity measurement.
    Nuclear Physics B - Proceedings Supplements 03/1999; 74(s 1–3):49–52. · 0.88 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: In recent years, measurements of azimuthal moments of polarized hadronic cross sections in hard processes have emerged as a powerful tool to probe nucleon structure. Many experiments worldwide are currently trying to pin down various effects related to nucleon structure through Semi-Inclusive Deep-Inelastic Scattering (SIDIS). Azimuthal distributions of final-state particles in semi-inclusive deep inelastic scattering, in particular, are sensitive to the orbital motion of quarks and play an important role in the study of Transverse Momentum Dependent parton distribution functions (TMDs) of quarks in the nucleon. The CLAS spectrometer, installed in Hall-B at Jefferson Lab, has collected semi-inclusive data using the CEBAF 6 GeV polarized electron beam on polarized solid NH3NH3 and ND3ND3 targets. An overview of these measurements is presented.
    Nuclear Physics B - Proceedings Supplements 01/2013; 234:58–61. · 0.88 Impact Factor

Full-text (2 Sources)

Available from
May 20, 2014