Related papers: Double Asymptotic Scaling '96
Recent measurements of inclusive and semi-inclusive measurements from the HERA collaborations are presented. The measurements include neutral current structure functions $F_2$, $F_L$ and $xF_3$; the charged current cross section including…
We report on the extension of the data fitting considering the QCD inspired model based on the summation of gluon ladders applied to the $ep$ scattering. In lines of a two Pomeron approach, the structure function $F_2$ has a hard piece…
We employ a parameterisation of the proton dipole cross section previously extracted from electroproduction and photoproduction data to predict the diffractive structure function F2D(3)(Q^2, beta, xpom). Comparison with HERA H1 data yields…
High energy factorization predictions for F2^c are derived using BFKL descriptions of the proton structure function F2 at HERA. The model parameters are fixed by a fit of F2 at small x. Two different approaches of the non perturbative…
We use recently proposed method of ratios to assess the quality of geometrical scaling in deep inelastic scattering for different forms of the saturation scale. We consider original form of geometrical scaling (motivated by the…
We use the Bessel-inspired behavior of the structure function F2 at small x, obtained for a flat initial condition in the DGLAP evolution equations. We fix the scale of the coupling constant, which eliminates the singular part of anomalous…
It is demonstrated that the global properties of the rapidity gap events at HERA can be understood based on electron-gluon scattering and a non-perturbative mechanism of colour neutralization. Using the measured inclusive structure function…
Recently the H1 collaboration has published a ``determination'' of the structure function F_L(x,Q^2) at low x. I address the question of how reliable this determination really is. I argue that it is in fact a consistency check of a given…
This talk covers three contributions from H1: "Measurement of the inclusive e^\pm p scattering cross section at high inelasticity y and of the structure function F_L", "Determination of the integrated luminosity at HERA using elastic QED…
Theoretical expectations concerning small $x$ behaviour of the spin dependent structure function $g_1$ are summarised. This includes discussion of the Regge pole model predictions and of the double $ln^2(1/x)$ effects implied by…
It is shown that a significant measurement of the longitudinal structure function $F_L(x,Q^2)$ can be performed at HERA, for $Q^2 = 2 GeV^2$ and $Q^2 = 5 GeV^2$ and for x around $10^{-4}$, using radiative events with hard photon emission…
We consider the effect of higher twist operators of the Wilson operator product expansion in the structure function $F_{2}(x,Q^{2})$ at small-$x$, taking into account QCD effective charges whose infrared behavior is constrained by a…
We present estimates of possible data on spin-dependent asymmetries in inclusive scattering of high energy polarized electrons by high energy polarized protons at HERA with their statistical errors and discuss systematic errors. We show…
Recent diffractive structure function measurements by the H1 and ZEUS experiments at HERA are reviewed. Various data sets, obtained using systematically different selection and reconstruction methods, are compared. NLO DGLAP QCD fits are…
We review and compare the reconstruction methods of the inclusive deep inelastic scattering variables used at HERA. We introduce a new prescription, the $\Sigma$ method, which allows to measure the structure function of the proton…
In this paper we show that the intuitive guess that the geometric scaling behaviour should be violated in the case of the running QCD coupling, turns out to be correct. The scattering amplitude of the dipole with the size $r$ depends on new…
We present a set of formulae to extract the longitudinal deep inelastic structure function $F_L$ from the transverse structure function $F_2$ and its derivative $dF_2/dlnQ^2$ at small $x$. Our expressions are valid for any value of…
We present the perturbative parts of the structure functions F_2^c and F_L^c for a gluon target having nonzero transverse momentum squared at order \alpha _s. The results of the double convolution (with respect to the Bjorken variable x and…
We perform a numerical study of the QCD corrections to the structure function $F_L(x,Q^2)$ in the HERA energy range. The $K$--factors are of $O(30%)$ and larger in parts of the kinematic range. The relative corrections to…
We present an analysis of the heavy quark structure functions from the $k_{t}$ factorization scheme, using unifying the color dipole picture and double asymptotic scaling approaches at small $x$. The gluon distribution is obtained from the…