Related papers: GALUGA, a Monte Carlo program for two-photon proce…
We compare two different approaches used for calculating cross sections for the two-photon $p p \to l^+ l^- X$ process. In one of the approaches photon is treated as a collinear parton in the proton. In the second approach a recently…
Ultra-peripheral collisions (UPCs) of heavy ions can be used as a clean environment to study two-photon induced interactions such as dilepton pair photoproduction. Recently, precise data on lepton pair production in UPCs were obtained by…
The construction of a Monte Carlo generator for high energy hadronic and nuclear collisions is discussed in detail. Interactions are treated in the framework of the Reggeon Field Theory, taking into consideration enhanced Pomeron diagrams…
Photon colliders (gamma-gamma, gamma-e) are based on backward Compton scattering of laser light off the high energy electrons of linear colliders. Recent study has shown that the gamma-gamma luminosity in the high energy peak can reach…
Hadron production in lepton-nucleus interactions at high-energies is considered in framework of developing Monte Carlo event generator HARDPING (HARD Probe INteraction Generator). Such effects as formation length, energy loss and multiple…
We present the recent developments in the precision studies of W-pair and single-W processes in e+e- collisions achieved with the help of the KoralW and YFSWW3 Monte Carlo generators. We focus on the theoretical precision of the…
We measure the cross section and the difference in rapidities between photons and charged leptons for inclusive W -> lnu+gamma production in egamma and mugamma final states. Using data corresponding to an integrated luminosity of 4.2 fb-1…
Exclusive hadron production processes in photon-photon collisions provide important tests of QCD at the amplitude level, particularly as measures of hadron distribution amplitudes and skewed parton distributions. The determination of the…
Monte Carlo event generators are the central interface between theoretical calculations and experimental measurements in collider physics. Over several decades, a comprehensive and highly modular ecosystem of tools has developed around…
We propose to use events with radiated photons in e^+e^- collisions to measure the total cross section of e^+ e^- \to hadrons as a function of the center of mass energy. The Monte Carlo simulation for the collider DAPHNE shows that a…
Secondary particles produced in spallation reactions of cosmic rays with the interstellar gas provide valuable information that allow us to investigate the injection and transport of charged particles in the Galaxy. A good understanding of…
Three studies on six-fermion production processes are presented, in which the production of an intermediate-mass Higgs boson, the top-quark physics and the analysis of possible anomalous quartic gauge couplings are considered. A Monte Carlo…
A simple Monte Carlo (MC) algorithm for the simulation of the passage of low-energy gamma rays and electrons through any material medium is presented. The algorithm includes several approximations that accelerate the simulation while…
The $O(\alpha m_t^2/m_W^2)$ Yukawa corrections to top pair production in photon-photon collision are calculated in the standard model (SM), the general two-Higgs-doublet model (2HDM) as well as the minimal supersymmetric model (MSSM). We…
We discuss the pair production of charginos in collisions of polarized photons $\gamma\gamma \to \tilde{\chi}_i^+ \tilde{\chi}_i^-$, ($i=1,2$) and the subsequent leptonic decay of the lighter chargino $\tilde{\chi}_1^+ \to \tilde{\chi}_1^0…
We present a method which extends Monte Carlo studies to situations that require a large dynamic range in particle number. The underlying idea is that, in order to calculate the collisional evolution of a system, some particle interactions…
We report a measurement of the differential cross section of $\pi^0$ pair production in single-tag two-photon collisions, $\gamma^* \gamma \to \pi^0 \pi^0$, in $e^+ e^-$ scattering. The cross section is measured for $Q^2$ up to 30 GeV$^2$,…
We consider the production of gravitons via two photon and electron-photon fusion in Kaluza-Klein theories which allow TeV scale gravitational interactions. We show that at electron-positron colliders, the processes l+l- -> l+ l- graviton,…
A fully massive Monte Carlo program to compute all four-fermion processes in electron positron collisions, including Higgs boson production, is presented. Leading higher order effects are discussed and included.
The cross-section for the process $\gamma + A \to \mu^+ + \mu^- + X$ is studied where the photon energy is of the order of several hundreds of GeV and where one of the leptons is scattered to large angles. This is of practical importance…