1,168 research outputs found
The nucleon's transversity and the photon's distribution amplitude probed in lepton pair photoproduction
We describe a new way to access the chiral odd transversity parton
distribution in the proton through the photoproduction of lepton pairs on
transversely polarized target. The basic ingredient is the interference of the
Bethe Heitler or Drell-Yan amplitudes with the amplitude of a process, where
the photon couples to quarks through its twist-2 chiral-odd distribution
amplitude. This approach permits to scan experimentally the shape of the
transversity distribution in a nucleon as well as the photon distribution
amplitude.Comment: 4 pages, proceedings of the ICHEP conference, Paris july 201
Neutrino-production of a charmed meson and the transverse spin structure of the nucleon
We calculate the amplitude for exclusive neutrino production of a charmed
meson on an unpolarized target, in the colinear QCD approach where generalized
parton distributions (GPDs) factorize from perturbatively calculable
coefficient functions. We demonstrate that the transversity chiral odd GPDs
contribute to the transverse cross section if the hard amplitude is calculated
up to order mc/Q. We show how to access these GPDs through the azimuthal
dependence of the nu N -> mu D N differential cross section.Comment: 5 pages, 1 figure. Version 2 adds a few clarifications and
references. As published in Physical Review Letters 115, 092001 (2015
Deeply Virtual Compton Scattering on the Deuteron
We study deeply virtual Compton scattering (DVCS) on a deuteron target. We
model the Generalized Quark Distributions in the deuteron by using the impulse
approximation for the lowest Fock-space state. Numerical predictions are given
for the unpolarized cross sections for the kinematical regimes relevant for
JLab and HERMES at HERA. Differential cross sections show the same pattern as
for the proton case and at low values of t they are of comparable size.Comment: 6 pages, 4 eps figures. Contribution to the European Workshop on the
QCD Structure of the Nucleon (QCD-N'02), Ferrara, Italy, 3-6 Apr 200
ELFE : an Electron Laboratory for Europe
This paper presents a brief overview of the physics with the 15-30~GeV
continuous beam electron facility proposed by the European community of nuclear
physicists to study the quark and gluon structure of hadrons.Comment: need qcdparis.sty, psfig and 8 eps figures : exclusive_hard_1.eps
exclusive_hard_2.eps exclusive_hard_3.eps hard_bw.eps gpm_slac.eps
inclusif1.eps inclusif2.eps machine.ep
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