相关论文: Diffractive Dissociation in Deep Inelastic Scatter…
The structure of real and virtual photons has been studied in ep collisions at HERA using dijet production. Measurements of differential dijet cross sections as function of the fraction of photon's momentum invested in the dijet system are…
Multiple interaction models satisfying $s$-channel unitarity predict that, in contrast to inelastic processes, factorization is violated in diffractive processes. The size of this effect can be characterized in terms of the rapidity gap…
The ZEUS detector has been used to study dissociation of virtual photons in events with a leading proton, gamma^* p -> X p, in e^+p collisions at HERA. The data cover photon virtualities in two ranges, 0.03<Q^2<0.60 GeV^2 and 2<Q^2<100…
Highlights selected from recent measurements of colour-singlet exchange processes at HERA are summarised. Particular emphasis is placed on energy and momentum transfer dependences and the decomposition of the data into an expansion in Regge…
Diffractive deep inelastic events with a large rapidity gap are analyzed by using a Regge model for the pomeron flux and a gluonic content for the pomeron. Contrary to the expectations, the simplest assumption for the pomeron trajectory…
This paper presents an analysis of the inclusive properties of diffractive deep inelastic scattering events produced in $ep$ interactions at HERA. The events are characterised by a rapidity gap between the outgoing proton system and the…
We discuss whether the diffractive structure functions defined by current experiments at HERA are indeed probing the partonic structure function of the pomeron. We observe that the {\it pseudorapidity} cuts commonly employed require that…
The high-energy behaviour of soft scattering observables such as total cross sections, elastic scattering at small momentum transfer, diffractive dissociation and central production have been described successfully in the context of Regge…
Measurements of diffractive phenomena observed at HERA are reviewed. A short introduction to the theoretical background is presented. The review focuses on the current experimental directions and discusses the exclusive production of vector…
A large collection of results for the diffractive dissociation of virtual photons, $\gamma^{\star}p \to Xp$, have been obtained with the H1 and ZEUS detectors at HERA. Different experimental techniques have been used, by requiring a large…
Recent results on diffraction at HERA, from the H1 and ZEUS Collaborations, and at Tevatron, from the CDF and D0 Collaborations, are reviewed. The measurement of the diffractive structure function at HERA is presented, and the pomeron…
Using the Good and Walker picture, we derive a simple formula for diffractive dissociation that can apply to recent data collected at HERA in the low Q2 regime.
A study is presented of the process gamma p -->XY, where there is a large rapidity gap between the systems X and Y. Measurements are made of the differential cross section as a function of the invariant mass mx of the system produced at the…
We investigate the role of unitarization effects in virtual photon-proton (\gamma^*p) interactions at small x. The q\bar{q}-fluctuation of the initial photon is separated into a small distance and a large distance component and a model for…
Recent HERA data on small-x structure functions as well as DIS diffraction and diffractive vector meson production are presented. The relationship between these processes and possible indications of dynamics beyond the DGLAP formalism are…
Exclusive diffractive production of real photons and vector mesons in ep collisions has been studied at HERA in a wide kinematic range. Here we present and discuss a Regge-type model of real photon production (Deeply Virtual Compton…
A large collection of results for the diffractive dissociation of virtual photons, $\gamma^{\star}p \to Xp$, have been obtained with the H1 and ZEUS detectors at HERA. Different experimental techniques have been used, by requiring a large…
The structure of the virtual photon and its contribution to small x processes in deep inelastic scattering at HERA is discussed.
Diffractive parton distributions of the proton are determined from fits to diffractive data from HERA. In addition to the twist--2 contribution, the twist--4 contribution from longitudinally polarised virtual photons is considered, which is…
Results are given on the measurements of the hard diffractive interactions at HERA $ep$ collider. The structure of the diffractive exchange in terms of partons and the factorisation properties are discussed, in particular by comparing the…