New possibilities of old soft pomeron in DIS

Abstract

A traditional Regge model with a $Q^2$-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 ($\chi^2/{dof}=1.11$) in the whole kinematical domain investigated by experiments. A comparison of the model with already existing ones is made. The $x-$, $Q^2-$slopes and the effective intercept are discussed as $Q^2$ and $x$ functions.Comment: 19 pages LaTeX, 10 eps figures included, one of figure captions is correcte

Regge models of the proton structure function with and without hard pomeron: A comparative analysis

“…Here, we consider two of them (and their modifications): the twoPomeron model of Donnachie and Landshoff [7] and the Soft Dipole Pomeron model [8], incorporating explicitly the ideas of universality for a Reggeon contribution (in the Born approximation) and of Q 2 -independent intercepts for Pomeron and f -Reggeon trajectories.…”

“…Though we consider in this Subsection only small x we give here the complete parameterization [8] valid also at large values of x; it will be fully exploited in the next Section. The forward scattering at W far from the s-channel threshold W th = m p is dominated by the Pomeron and the…”

“…Thus, the Soft Dipole Pomeron (SDP) model was generalized for the virtual photon-proton amplitude and applied to the proton structure function (SF) in a wide kinematical region of deep inelastic scattering [8]. This model also has two Pomeron components, each of them with intercept α P (0) = 1, one is a double pole and the other one is a simple pole.…”

The additive quark model revisited: Hadron- and photon-induced cross sections

“…As shown in [17], the Pomeron contribution at t = 0 is more complicate than (1) because each term in (4) and (5) should be multiplied by a priori different vertex functions G(t). Thus, at t = 0, (1) must be rewritten as…”

Q2-evolution of parton densities at small x values and H1 and ZEUS experimental data

“…Contrary to the approach in [11]- [14] various groups have been able to fit the available data using a hard input at small x: x −λ , λ > 0 with different λ values at low and high Q 2 (see [20]- [26]). Such results are well-known at low Q 2 values [21].…”