Related papers: $\Delta$ contribution in $e^+ + e^- \to p + \bar{p…
Two-photon exchange contributions to elastic electron-proton scattering cross sections are evaluated in a simple hadronic model including the finite size of the proton. The corrections are found to be small in magnitude, but with a strong…
The complete calculation of the 2-loop electroweak corrections to the renormalization of the electric charge in the Standard Model allows to discuss in detail the value of the MSbar effective coupling $\hat e(m_Z)$. We discuss the…
We provide complete analytic expressions for the isolated prompt photon production cross section in $e^+e^-$ annihilation reactions through one-loop order in quantum chromodynamics (QCD) perturbation theory. Functional dependences on the…
The emission of the hard photon by the initial state is considered. The nucleon polarization and the differential cross sections for some experimental conditions have been calculated. The case of the emission of the collinear (with respect…
For $\pi^0\eta$-photoproduction on the nucleon formal expressions are developed for the five-fold differential cross section and the recoil polarization including beam and target polarizations. The polarization observables are described by…
We reevaluate the dispersion integrals of the leading order hadronic contributions to the running of the QED fine structure constant alpha(s) at s=M_Z^2, and to the anomalous magnetic moments of the muon and the electron. Finite-energy QCD…
The polarization of the $\Lambda$ and $\overline\Lambda$ hyperons along the beam ($z$) direction, $P_{\rm z}$, has been measured in Pb-Pb collisions at $\sqrt{s_{\rm NN}}$ = 5.02TeV recorded with ALICE at the Large Hadron Collider (LHC).…
Correlations of non-photonic electrons with charged hadrons are studied using the PYTHIA Monte Carlo event generator in p+p collisions at $\sqrt{s_{NN}} = 200$ GeV. We propose experimental methods to estimate the relative contributions to…
We present a thorough phenomenological analysis of the experimental data from Belle Collaboration for the transverse $\Lambda$ and $\bar\Lambda$ polarisation, measured in $e^+e^-$ annihilation processes, for the case of inclusive (plus a…
We present an analytical description of top-antitop pair production near the threshold in $e^+e^-$ annihilation and $\g\g$ collisions. A set of basic observables considered includes the total cross sections, forward-backward asymmetry and…
Radiative corrections to the annihilation of proton--antiproton into electron--positron are revisited, including virtual and real (soft and hard) photon emission. This issue is relevant for the time-like form factors measurements planned at…
We begin with short review of the analytic approach (AA) to QCD recently developed and applied to the process of $e^+e^-$ annihilation into hadrons at low energies. Besides summary of the theoretical description of smeared experimental data…
Data on the polarization observables T, P, and H for the reaction $\gamma p\to p\pi^0$ are reported. Compared to earlier data from other experiments, our data are more precise and extend the covered range in energy and angle substantially.…
In two earlier papers it was demonstrated that Lorentzian and Galilean symmetries could both be useful in the analysis of the annihilation reaction $e^+ e^- \to \gamma \Lambda(\rightarrow p\pi^-) \bar{\Lambda}(\rightarrow \bar{p}\pi^+)$. It…
We calculate the longitudinal contribution to the alignment polarization $\Pl$ of quarks produced in $e^+e^-$ annihilation. In the Standard Model, the longitudinal alignment polarization vanishes at the Born term level and thus receives its…
In this work, the two-photon-exchange (TPE) effects in $e^+e^- \rightarrow \pi^+ \pi^-$ at small $\sqrt{s}$ are discussed within a hadronic model. In the limit $m_e\rightarrow 0$, the TPE contribution to the amplitude can be described by…
In pp collisions at 1.25 GeV kinetic energy, the HADES collaboration aimed at investigating the di-electron production related to $\Delta$ (1232) Dalitz decay ($\Delta^+ \to pe^+e^-$). In order to constrain the models predicting the cross…
The pd <--> pi+ t process has been calculated in the energy region around the Delta-resonance with elementary production/absorption mechanisms involving one and two nucleons. The isobar degrees of freedom have been explicitly included in…
It is shown that simple extension of the modified negative binomial distribution describes negatively charged particle multiplicity distributions in e+e- annihilation, measured in the whole phase space, as well as the modified negative…
Nonleptonic decays of charmed mesons into two pseudoscalar mesons or one pseudoscalar meson and one vector meson are studied on the basis of a generalized factorization method considering the resonance effects in the pole model for the…