A. Lengyel

The hard pomeron in soft data

Abstract We show that the data for the total cross section and for the real part of the elastic amplitude indicate the presence of a hard pomeron in πp and Kp elastic scattering at t=0, compatible with that observed in deep inelastic scattering. We show that such a hard pomeron is also compatible with pp and p p data, provided one unitarises it at high energy.

Soft and hard Pomerons in hadron elastic scattering at small t

We consider simple-pole descriptions of soft elastic scattering for pp, ¯ pp, � ± p and K ± p. We work at t and s small enough for rescatterings to be neglected, and allow for the presence of a hard pomeron. After building and discussing an exhaustive dataset, we show that simple poles provide an excellent description of the data in the region −0.5 GeV 2 ≤ t ≤ −0.1 GeV 2 , 6 GeV≤ √ s ≤ 63 GeV. We show that new form factors have to be used, and get information on the trajectories of the soft and hard pomerons.

New possibilities of old soft pomeron in DIS

A traditional Regge model with a

Pomeron effective intercept, logarithmic derivatives of F2(x,Q2) in DIS and Regge models.

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How fast do small x structure functions rise? A comparative analysis

-independent Pomeron intercept closed (or equal) to one is constructed in order to describe the available data on the proton structure function. A Dipole Pomeron model which does not explicitly violate unitarity is developed and investigated. An excellent agreement with the 1209 data is found (

Small x extrapolation of structure functions and the Pomeron

\chi^2/{dof}=1.11

Finite sum of gluon ladders and high energy cross sections

) in the whole kinematical domain investigated by experiments. A comparison of the model with already existing ones is made. The

Describing F2 through a finite sum of gluon ladders

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A review of the hard pomeron in soft diffraction

,

Damping of the HERA effect in DIS

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