相关论文: Analysis of Rapidity Gap Cuts in Diffractive DIS
With the knowledge of diffractive parton densities extracted from HERA data, we discuss the observation of exclusive events using the dijet mass fraction as measured by the CDF collaboration at the Tevatron. In particular the impact of the…
It is commonly believed that decoherence is the main obstacle to quantum information processing. In contrast to this, we show how decoherence in the form of dissipation can improve the performance of certain quantum gates. As an example we…
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…
The e^+p neutral-current deep inelastic scattering differential cross-sections $d\sigma/dQ^2$, for Q^2 > 400 GeV^2, $d\sigma/dx$ and $d\sigma/dy$, for Q^2 > 400, 2500 and 10000 GeV^2, have been measured with the ZEUS detector at HERA. The…
Large Rapidity Gap Events in Deep Inelastic Scattering are discussed in terms of lightcone wave functions for quarks and gluons inside the photon. It is shown that this approach is consistent with earlier, conventional Feynman diagram…
A search for photoproduction events which contain a rapidity gap between the two highest transverse energy jets has been conducted at HERA using the ZEUS detector. The jets have transverse energies greater than 6~GeV, and are separated by…
We investigate the azimuthal distribution of quark-antiquark jets in DIS diffractive dissociation with large transverse momentum. In this kinematical region the matrix element is expressed in terms of the gluon structure function. For the…
The existing data obtained in deep-inelastic scattering (DIS) experiments in the kinematical region $x_B \approxle 10^{-2}$ and $Q^2 \ge 5 {GeV}^2$ are examined to gain further insight into the dynamics of interacting gluons. It is shown…
The production of dijets in diffractive deep inelastic scattering has been measured with the ZEUS detector at HERA using an integrated luminosity of $61 \pbi$. The dijet cross section has been measured for virtualities of the exchanged…
Cuprate high-temperature superconductors exhibit a pseudogap in the normal state that decreases monotonically with increasing hole doping and closes at x \approx 0.19 holes per planar CuO2 while the superconducting doping range is 0.05 < x…
A search for QCD instanton (I) induced events in deep-inelastic scattering (DIS) at HERA is presented in the kinematic range of low x and low Q^2. After cutting into three characteristic variables for I-induced events yielding a maximum…
A model for the production of large rapidity gaps being implemented in the Monte Carlo event generator PHOJET is discussed. In this model, high-mass diffraction dissociation exhibits properties similar to hadron production in…
Deep inelastic scattering (DIS) events, selected from 1993 data taken by the H1 experiment at HERA, are studied in the Breit frame of reference. The fragmentation function of the quark is compared with those of \ee data. It is shown that…
Preliminary results from H1 and ZEUS on Deep Inelastic Scattering (DIS) at high momentum transfer squared $Q^2$ are presented. Used are all available $e^+ p$ data accumulated by the H1 and ZEUS experiments between 1994 and 1997,…
The H1 and ZEUS experiments are measuring diffractive interactions in ep collisions at HERA. Performing QCD fits of these data with NLO DGLAP, diffractive parton distribution functions can be calculated. These diffractive PDFs can be used…
The dipole and the DGLAP approximations are combined with the $k_t$ factorization theorem to demonstrate the fundamental property of pQCD: smaller is the size of the colorless quark-gluon configurations in the fragmentation region, more…
The inclusive photoproduction of D\ast mesons and of D\ast-tagged dijets is investigated with the H1 detector at the ep collider HERA. The kinematic region covers small photon virtualities Q2 < 2 GeV2 and photon-proton centre-of-mass…
The results of complementary tests of perturbative QCD in DIS at large centre-of-mass energies at HERA are presented. The analysis of event shape variables allows for the investigation of approaches to understand aspects of non-perturbative…
To understand the interplay of d-wave superconductivity and antiferromagnetism in the cuprates, we consider a two-dimensional extended Hubbard model with nearest neighbor attractive interaction. Free energy of the homogeneous (coexisting…
The data on the diffractive deep inelastic scattering (DDIS) at HERA exhibit a strong excess, up to about 100%, above the twist-two NLO DGLAP description at low $Q^2$ and at large energy. I show, that complementing the DGLAP fit by twist 4…