365 research outputs found
Collins Effect from Polarized SIDIS and Data
The recent data on the transverse single spin asymmetry
from HERMES and COMPASS Collaborations are
analysed within LO parton model with unintegrated parton distribution and
fragmentation functions. A fit of SIDIS data from HERMES Collaboration is
performed leading to the extraction of favoured and unfavoured Collins
fragmentation functions. A very good description of COMPASS data is obtained.
BELLE data are shown to be compatible with our estimates based on the
extracted Collins fragmentation functions. Predictions for
asymmetries at JLab and COMPASS operating on a
proton target are given.Comment: Talk presented at SPIN2006, 4 pages, 6 figure
The First Three Pomerons
A model of a three Pomeron contribution to high energy elastic and scattering is proposed. The data are well described for all momenta
() and energies ()
(). The model predicts the appearance of two dips in
the differential cross-section which will be measured at LHC. The parameters of
the Pomeron trajectories are: Comment: 26 pages, 16 figure
Regge-Eikonal Approach and its off-Shell Extention Versus Experimental Data
We develop an off-shell extention of the Regge-eikonal approach which
automatically takes into account off-shell unitarity. We argue that exclusive
vector-meson production cross-sections measured at HERA can be fairly described
with classical universal Regge trajectories. No extra ``hard'' trajectories of
high intercept are needed for that.Comment: 15 pages, 18 figures, uses ws-p8-50x6-00.cls, epsf.sty, amsfonts.sty,
to be published in the Proceedings of the International Conference on Elastic
and Diffractive Scattering (VIIIth 'Blois Workshop') June 28 - July 2, 1999
Protvino, Russi
Partonic Transverse Motion in Unpolarized Semi-Inclusive Deep Inelastic Scattering
We analyse the role of partonic transverse motion in unpolarized
Semi-Inclusive Deep Inelastic Scattering (SIDIS) processes. Imposing
appropriate kinematical conditions, we find some constraints which fix an upper
limit to the range of allowed kt values and lead to interesting results,
particularly for some observables like the azimuthal modulation of
the unpolarized SIDIS cross section and the average transverse momentum of the
final, detected hadron.Comment: To appear in the Proceedings of the XIX International Workshop on
Deep-Inelastic Scattering and Related Subjects (DIS 2011), April 11-15, 2011,
Newport News, VA US
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