Related papers: Resolved photon and multi-component model for $\ga…
Complementary to the conventional experimental studies on $N^*$ from $\pi N$ and $\gamma^{(*)}N$ reactions, the $e^+e^-$, $pp$ and $p\bar p$ collisions can give novel insights into these $N^*$ resonances. While the $e^+e^-$ collisions…
The cross--section for two--photon events with (at least) two independent partonic scatters is estimated, for LEP energies as well as a 500 GeV ``photon collider". This results in events with (at least) four central (mini--)jets. Such…
The main possibilities of investigation of leptons and bosons production in interaction of polarized photons are considered. The usage of $\gamma\gamma\to f\bar{f}[+\gamma]$ reactions for the luminosity measurement on linear photon collider…
Virtual Compton Scattering off the proton: gamma* p to gamma p, is a new field of investigation of nucleon structure. Several dedicated experiments have been performed at low c.m. energy and various momentum transfers, yielding specific…
The factorization theorem for organizing multiple electroweak boson emissions at future colliders with energy far above the electroweak scale is formulated. Taking the inclusive muon-pair production in electron-positron collisions as an…
In this contribution we present the main results of the investigation about double parton scattering (DPS) in quasi-real photon-proton interactions. We show the first evaluation of the DPS cross-section at leading-order for the four-jet…
We present results for total cross sections, single and double differential distributions and correlations between pairs of outgoing particles in the reactions p + antip --> W^+ + photon and p + antip --> W^+ + photon + jet at sqrt(S)=1.8…
I discuss the minijet contribution to total photoproduction and photon--photon cross sections. While minijets with $p_T$ around 2 GeV have recently been observed directly in \gamgam\ experiments, the total \gamp\ cross section measured at…
The standard additive quark model and the ensuing counting rules are modified to take into account the quark-gluonic content of the Pomeron and of the secondary Reggeons. The result is that a much improved description of $pp, \pi p, \gamma…
We show the usefulness of an $e^-\gamma$ collider with backscattered laser photons in unveiling the signatures of Gauge-Mediated Supersymmetry Breaking models, with a right selectron as the next LSP. We also show how the signal can be…
We consider the problem of constructing reduced models for large scale systems with poles in general domains in the complex plane (as opposed to, e.g., the open left-half plane or the open unit disk). Our goal is to design a model reduction…
In this talk we present an update of model predictions for the $\gamma \gamma$ total cross-section in the TeV region. The update includes preliminary results for $\gamma \gamma $ cross-sections using the Bloch-Nordsieck model for the…
We apply the complex scaling method to the calculation of scattering phase shifts and extract the contributions of resonances in a phase shift and a cross section. The decomposition of the phase shift is shown to be useful to understand the…
We discuss a possibility to measure the photon-photon scattering cross section at low energy in a theoretical standpoint. The cross section of photon-photon scattering at low energy can be written as $\displaystyle{{d\sigma\over d\Omega}…
We calculate the unpolarized QED Compton scattering cross section in a manifestly covariant way. Our approach allows a direct implementation of the specific kinematical cuts imposed in the experiments, {\it e. g.} HERA-H1. We compare the…
We present an approximation to the matrix element for the process e+e- --> e+e-gamma, appropriate to the situation where one or both of the fermions are scattered over very small angles. The leading terms in the situation where all…
We make a QCD-inspired parameterization of all accelerator data on forward proton-proton and antiproton-proton scattering amplitudes. Using vector dominance and the additive quark model, we show that the same parameters also fit gamma p and…
We show how to attach an external photon to a system of three strongly interacting nucleons described by three-body scattering equations. Our method involves the idea of gauging the scattering equations themselves, and results in…
We calculate the Compton scattering for photon and gluon with the Klein-Nishina formula in fixed-target collisions by using the proton and lead beams at AFTER@LHC. In these collisions, we can investigate the particular case of Compton…
Multi-photon split states, where each photon is in a different spatial mode, represent an essential resource for various quantum applications, yet their efficient characterization remains an open problem. Here, we formulate the general…