Related papers: Physics with two photons at HERA
Inclusive neutral and charged current cross sections and structure functions measured at HERA-I are briefly reviewed. The impact of these measurements on parton density functions is discussed. The emphasis is put on the high x region. A…
The exclusive diffractive production of vector mesons and real photons in ep collisions has been studied at HERA in a wide kinematic range. Here the most recent experimental results are presented together with a Regge-type model and…
Recent results from HERA are presented. The main reviewed subjects are polarized DIS cross sections, parton density determination, diffractive PDFs, multi-jet production and searches for physics beyond the Standard Model.
In this contribution, we show that the use of conditional measurements in the resonant interaction of two quantized electromagnetic fields gives rise to nonclassical multiphoton processes. Furthermore, we demonstrate that this phenomenon…
Jet production in electron-proton collisions at HERA provides a unique testing ground for Quantum Chromodynamics (QCD). Apart from the determination of the strong coupling constant $\alpha_s$, ep jet data may especially be used to gain…
Recent results on spectroscopy with special focus on searches for pentaquarks are presented from the H1 and ZEUS collaborations. Cross sections of observed states and upper limits on the production cross section of unobserved states are…
We discuss polarized proton-positron scattering in the context of the excess of large $Q^2$ events at HERA. We define and estimate a polarized asymmetry to examine two scenarios, the contact interaction and the stop scenario with broken…
In this paper, we study two-photon interference with the approach of photon quantum theory, with specific attention to the two-photon interference experiment carried out by Milena D'Angelo et al. (Phys. Rev. Lett 87:013602, 2001). We find…
Hadronic interactions of two quasi-real photons have been studied extensively both during the LEP1 and the LEP2 data taking periods. The higher energies available at LEP2 in particular opened regions of phase space where hadronic processes…
HERA, the first electron-proton collider, has been delivering luminosity since 1992. It is the natural extension of an impressive series of fixed-target lepton-nucleon scattering experiments. The increase of a factor ten in center-of-mass…
The structure of real and virtual photons has been studied in electron-proton scattering processes producing di-jet events at HERA by the H1 and ZEUS collaborations. Data have been compared to next-to-leading order QCD calculations and to…
We review the current situation in polarized scattering experiments. We describe the theoretical interpretation of inclusive deep inelastic processes, the current experimental situation and perturbative analyses which extract structure…
The prospects for physics at the LHC are discussed, starting with the foretaste, preparation (and perhaps scoop) provided by the Tevatron, in particular, and then continuing through the successive phases of LHC operation. These include the…
Two-photon exchange contributions to elastic electron-scattering are reviewed. The apparent discrepancy in the extraction of elastic nucleon form factors between unpolarized Rosenbluth and polarization transfer experiments is discussed, as…
Several issues related to pentaquark searches relevant for current and future high-energy colliding experiments are discussed. We make an attempt to explain why pentaquark candidates are not seen by some experiments, and what makes the HERA…
It is well understood that the studies of correlations between produced particles, the effects of coherence and chaoticity, an estimation of particle emitting source size play an important role in high energy physics [1]. We mean the…
The electron-proton collisions collected by the H1 and ZEUS experiments at HERA comprise a unique particle physics data set, and a comprehensive range of measurements has been performed to provide new insight into the structure of the…
In these lectures I introduce the basics of HERA physics and give a survey of the major aspects, discussing in somewhat more depth the subject of low $x$ physics.
Charged current events are studied at HERA with polarized beams, using a Monte Carlo event generator and taking into account detector smearing effects. The observed asymmetries are used to study the extraction of the polarized structure…
In central collisions at relativistic heavy ion colliders like the Relativistic Heavy Ion Collider RHIC/Brookhaven and the Large Hadron Collider LHC (in its heavy ion mode) at CERN/Geneva, one aims at detecting a new form of hadronic matter…