Related papers: Hard Photon Pair Production at LEP
The main possibilities of investigation of leptons and bosons birth 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…
The $O(\alpha)$ corrections to $\gamma\gamma --> f \bar f$ in the Standard Model are calculated for arbitrary, light fermions $f$. The relevant analytical results are listed in a form that is appropriate for practical applications, and…
In this paper we consider the production of proton-antiproton pairs in two-photon interactions in electron-positron and heavy-ion collisions. We try to understand the dependence of the total cross section on the photon-photon c.m. energy as…
The feasibility of observing true tauonium, the bound state of two tau leptons, $\mathcal{T}_0\equiv(\tau^+\tau^-)_0$, via photon-photon collisions at $e^+e^-$ colliders and at the LHC, is studied. The production cross sections of the…
Charm production is studied in deep-inelastic electron-photon scattering using OPAL data at e+e- centre-of-mass energies from 183 to 209 GeV. Charm quarks are identified by exclusive reconstruction of D* mesons. The cross-section of D*…
In this present paper, we investigate the muon pairs production in the interaction between two quasireal photons in $e^+e^-$ collision. The total and differential cross section of the process $\gamma \gamma \to \mu^+\mu^-$ at a beam energy…
We investigate the $J/\psi$ + c + $\bar{c}$ photoproduction in $e^+ e^-$ collision at the LEP II energy. The physical motivations for this study are: 1) such next-to-leading order(NLO) process was not considered in previous investigations…
The production rate and kinematics of photons produced in association with Z bosons are studied using 2/fb of p\bar{p} collision data collected at the Collider Detector at Fermilab. The cross section for p\bar{p} -> l^+ l^- gamma + X (where…
Cross section of the processes of neutral pion production as well as pairs of charged fermions and bosons in peripherical interaction of leptons, photons are calculated in main logarithmical approximation. We investigate the phase volumes…
Heavy quark production in multijet events at $e^+e^-$ colliders is studied at tree level. Total production rates are given and compared with the corresponding results for massless quarks. A new method of computing helicity amplitudes is…
In this preprint we analyzed the exclusive photoproduction of $\eta_{c}\gamma$ pairs in the collinear factorization framework and evaluated its cross-section in leading order in the strong coupling $\alpha_{s}$. We found that this process…
We consider the reaction $\gamma p \to M p$, with M being either a $\Phi$ or a $J/\Psi$ meson, within perturbative QCD treating the proton as a quark-diquark system. The phenomenological couplings of gauge bosons to (spatially extended)…
We discuss production of $J/\psi$ and $e^+ e^-$ pairs in semicentral and peripheral collisions of heavy ions at high energies. We focus on photoproduction mechanism. We present explanation of results of the ALICE collaboration for low…
The heavy ion total cross section for continuum e+ e- pair production has been calculated to all orders in Z alpha. The formula resulting from an exact solution of the semiclassical Dirac equation in the ultrarelativistic limit is evaluated…
The charged Higgs pair production via photon-photon collisions is investigated in the framework of two Higgs doublet model (2HDM), taking into account a full set of one-loop-level scattering amplitudes, i.e., including electroweak (EW)…
Fermion pair production at $e^-e^+$ linear collider experiments with polarized $e^-$ and $e^+$ beams is examined in the GUT inspired $SO(5)\times U(1)\times SU(3)$ gauge-Higgs unification. There arises large parity violation in the…
Photoproduction is an important mode for the production of jets and electro-weak particles at lepton--lepton and lepton--hadron colliders and allows for interesting studies of exclusive production at hadron--hadron colliders. In this talk,…
Open heavy flavour production at $e^+e^-$ colliders in deeply inelastic $e\gamma$ scattering has an interesting feature: the structure function $F_2(x,Q^2)$ for this process is calculable for $x>0.01$, and is essentially proportional to the…
The production of hard di-jet events in photoproduction at HERA is dominated by resolved photon processes in which a parton in the photon with momentum fraction x_gamma is scattered from a parton in the proton. These processes are sensitive…
The first observation of $\tau$ lepton pair production in ultraperipheral nucleus-nucleus collisions, a pure quantum electrodynamics (QED) process, is presented. The measurement is based on a data sample collected by the CMS experiment at a…