Related papers: Exclusive double $B_c$ meson production from $e^+e…
The production of mesons in ultra-peripheral collisions of relativistic heavy ions is re-analyzed using a projection technique to calculate the amplitudes for the appropriate Feynman diagrams. The virtuality of the exchanged photons is…
We study the exclusive production of scalar $S = 0^{++}$ and tensor $T = 2^{++}$ mesons through single-photon annihilation $e^+ e^- \to \gamma^* \to \gamma S(T)$. Using QCD compositeness of the involved hadrons considered as quark-antiquark…
In the framework of perturbative QCD and nonrelativistic bound state formalism, we calculate the production of $B_c$ and $B_c^*$ mesons at the conditions of the CDF and LHCb experiments. We derive first estimations for the $B_c$ wave…
The $B_c$ meson pair, including pairs of both pseudoscalar states and vector states, productions in high energy photon-photon interaction are investigated at the next-to-leading order (NLO) accuracy in the nonrelativistic quantum…
Recent measurements of the Belle Collaboration of the exclusive production of two charmonia in the $e^+e^-$ annihilation differ substantially from theoretical predictions. Recently it was suggested that a significant part of this…
We discuss pion pair production in two-photon collisions in two different kinematical regimes. When both photons are real and at moderately large center-of-mass energy s we elaborate on partonic transverse momentum and Sudakov corrections…
We present a theoretical estimation for the cross-section of exclusive two $\rho$-meson production in two photon collision when one of the initial photons is highly virtual. The compatibility of our analysis with recent experimental data…
With respect to the two theoretical approaches for estimating the hadronic productions of the mesons $B_c$ and $B_c^*$: the full $\alpha_s^4$ calculation and the fragmentation approximation, with a thorough comparative study a quite…
In this paper the production of excited vector and pseudoscalar charmonium mesons in $\epem$ annihilation is analyzed in the framework of light cone. In particular the cross sections $\epem \to \psi(2S)\eta_c(1S),…
We discuss nuclear cross sections for $AA \to AAV$ and $AA \to AAVV$ reactions with one or two vector mesons in the final state. Our analysis is done in the impact parameter space equivalent photon approximation. This approach allows to…
We present a reliable estimate on the production rate of $B_c$ mesons in $1S$ and $2S$ states in the large transverse momentum region at hadronic colliders using heavy quark fragmentation functions derived within the framework of…
Experiments that study the photoproduction of pseudoscalar mesons; pions, etas and kaons, have the potential to increase our knowledge of baryon and hyperon resonance properties. Recent experiments at JLab, Mainz, GRAAL, and Bonn are…
Starting from a bound-state model of weakly bound quarks for ($q \bar{q}$) mesons, we derive a formalism for computing the production or decay of such mesons, whatever the value of their internal orbital angular momentum L. That approach…
Within the framework of the perturbative QCD approach, we calculate the time-like $B_cB_c(B_c^*)$ form factors $F(Q^2)$ and $A_2(Q^2)$. We include relativistic corrections and QCD corrections, either of which can give about $20\%$…
We investigate selectron pair production and decay in e-e- scattering and e+e- annihilation with polarized beams taking into account neutralino mixing as well as ISR and beamstrahlung corrections. One of the main advantages of having both…
The STAR collaboration has observed an excess production of $e^+e^-$ pairs in relativistic heavy ion collisions, over the expectations from hadronic production models. The excess pairs have transverse momenta $p_T < 150\ {\rm MeV}/c$ and…
We present first measurable predictions for electromagnetic (two-photon) double scattering production of two positron-electron pairs in ultraperipheral heavy-ion collisions at LHC. Measureable cross sections are obtained with realistic cuts…
Calculations of the hadronic $B^{(*)}_c$-mesons production performed in the framework of the perturbative QCD taking into account $O(\alpha_s^4)$ Feynmann diagrams are presented. A comparison of the exact calculations with those based on…
A simple extension of the QCD inspired potential model which includes dynamical quarks first proposed by Eichten et al. is remarkably successful in accounting both for the observed narrow state heavy quarkonium spectroscopy and experimental…
In this work, we investigate a novel production mechanism of vector mesons, exemplified by the production of a neutral vector meson associated with a lepton pair in $e^+e^-$ annihilation, i.e., $e^+e^-\to V l^+l^-$ ($V=J/\psi, \rho^0,…