ar X iv : h ep - p h / 00 06 08 2 v 2 1 3 Ju n 20 00 LUNFD 6 / ( NFFL - 7187 ) 2000 PHOTON STRUCTURE AT HERA

ar X iv : h ep - p h / 00 06 19 3 v 1 1 6 Ju n 20 00 ERROR PROPAGATION IN QCD FITS

The parton momentum density distributions of the proton were obtained from a NLO QCD analysis of HERA and fixed target structure function data. The resulting parton distribution set includes the full information on errors and correlations.

ar X iv : h ep - p h / 00 06 32 1 v 1 2 8 Ju n 20 00

We compute amplitude of deeply virtual Compton scattering in the parton model. We found that the amplitude in the hard regime up to the accuracy O(1/Q) depends on new skewed parton distributions (SPD's). These additional contributions make the DVCS amplitude explicitly transverse. The new SPD's contribute to various spin, charge and azimuthal asymmetries at the same order in 1/Q as the leading ...

X iv : h ep - t h / 00 06 09 7 v 1 1 4 Ju n 20 00 Interaction of electric charges in ( 2 + 1 ) D magnetic dipole gas

ar X iv : h ep - p h / 06 06 21 3 v 1 20 J un 2 00 6

In principle, leading neutrons produced in photoproduction and deep-inelastic scattering at HERA have the potential to determine the pion structure function, the neutron absorptive cross section and the form of the pion flux. To explore this potential we compare theoretical predictions for the xL and pt spectra of leading neutrons, and the Q 2 dependence of the cross section, with the existing ...

ar X iv : h ep - e x / 00 08 06 5 v 1 2 6 A ug 2 00 0 Search for Large Extra Dimensions in Dielectron and Diphoton Production