Related papers: Some remarks on geometric scaling
The next-to-leading QCD calculation for the isolated photon and isolated photon plus jet photoproduction at the ep collider DESY HERA is presented. The theoretical uncertainties are discussed in details. The predictions are compared with…
We discuss two different models for the impact parameter dependent dipole cross section: one based on DGLAP evolution and the other inspired by the Balitsky-Kovchegov equation. The parameters are determined from fits to data on the total…
We study two and three jet events with a large rapidity gap at HERA. Unlike in the Ingelman-Schlein approach we do not adscribe a structure to the Pomeron. Instead, the coupling of the Pomeron to quarks or gluons is taken pointlike, which…
We use the dipole model to analyze the inclusive DIS cross section data, obtained from the HERA I+II measurements \cite{Abramowicz:2015mha}. We show that these combined data are very well described within the dipole model framework, which…
We study photoproduction reactions in a polarized ep collider mode of HERA at sqrt(s)=298 GeV. We examine the sensitivity of the cross sections and their asymmetries to the proton's polarized gluon distribution and to the completely unknown…
We provide a universal expression of cross sections for the exclusive vector meson production and Deeply Virtual Compton Scattering (DVCS) in photon-proton and photon-nucleus interactions based on the geometric scaling phenomenon. The…
HERA is the only high energy electron-proton collider in the world today and hence has unique opportunities both to probe the structure of the proton and to search for physics beyond the Standard Model. Results are presented for…
Results are presented of a study of the experimental and theoretical accuracy one may achieve at HERA in measuring the strong coupling constant alpha_s and the gluon distribution from scaling violations of F2 structure functions.
Differential dijet cross sections in diffractive deep-inelastic scattering are measured with the H1 detector at HERA using an integrated luminosity of 51.5 pb-1. The selected events are of the type ep --> eXY, where the system X contains at…
We show that a peripheral meson model can explain the large deep inelastic electron-proton scattering rapidity gap events observed at HERA.
Standard parton distribution functions contain neither information on the correlations between partons nor on their transverse motion, then a vital knowledge about the three dimensional structure of the nucleon is lost. Hard exclusive…
We re\,examine the theory of hadronic photon-nucleon interactions at the quark-gluon level. The possibility of multiple parton collisions in a single photon-nucleon collision requires an eikonal treatment of the high-energy scattering…
We study the feasibility of measuring semi-exclusive photon production \gamma + p \to \gamma + Y at HERA. The cross section of photons produced at large transverse momenta, recoiling off an inclusive system Y of limited mass, can without…
A successful interpretation of the cross sections for elastic and inelastic vector meson production can be made if one assumes the underlying dynamics to be governed by hard partonic subprocesses. Extending these partonic approaches to…
We present a model of proton geometry where the number and size of gluon density hotspots in the proton's thickness function evolves with the resolution scale of the event given by the Mandelstam $t$ variable in exclusive diffractive $ep$…
We investigate the transverse parton distribution of the proton through the t-dependence of the coherent J/psi differential cross section extracted from HERA measurements in the small-x regime. Employing a simple static Gaussian hot spot…
The possibility of jet energy scale setting at the CMS calorimeter by using photon+jet process is studied. The estimation of the number of photon+jet events suitable for determination of gluon distribution inside a proton in a new kinematic…
We propose a new criterium for saturation of the density of partons both in nucleons and nuclei. It is applicable to any multiple scattering model which would be used to compute the number of strings exchanged in $ep$ and $eA$ collisions.…
The measurement of the proton structure function at HERA is often seen as a hint for the observation of saturation in high-energy QCD e.g. through the observation of geometric scaling. Accordingly, the dipole picture provides a powerful…
Recent results from the ep (electron-proton) collider HERA are presented. Jet production and diffraction type reactions allow tests of predictions of Quantum Chromodynamics (QCD). Jet measurements are used to improve the combined H1-ZEUS…