Related papers: A possible resolution of the e+e- --> Nbar N puzzl…
The BaBar collaboration has an extensive program of studying hadronic cross sections in low-energy e+e- collisions, accessible via initial-state radiation. Our measurements allow significant improvements in the precision of the predicted…
The processes $e^{+}e^{-} \to \Delta^{++}\bar{\Delta}^{--}$ and $e^{+}e^{-}\to \Delta^{++} \bar{p} \pi^{-} + c.c.$ are studied for the first time with $179~{\rm pb}^{-1}$ of $e^{+}e^{-}$ annihilation data collected with the BESIII detector…
The nonresonant mechanism in the reactions $e^+\,e^-\to \pi^-\,p\,\bar{n}$ and $e^+\,e^-\to \pi^+\,n\,\bar{p}$ is investigated in frame of the one-photon exchange approximation. The description of the hadronic phase space and the invariant…
The study of the charmed baryons is crucial for investigating the strong and weak interactions in the Standard Model and for gaining insights into the internal structure of baryons. In an $e^+e^-$ experiment the lightest charmed baryon,…
Recently, several surprising experimental observations in the production of heavy quarkonium have been reported. In $e^+e^-$ annihilation at $\sqrt{s}=10.6$ GeV, Belle Collaboration finds that $J/\psi$ mesons are predominantly produced in…
The excitation curve of e+e- annihilation into four charged pions in the rho(770) region is calculated using three existing models with rho mesons and pions in intermediate states supplemented by Feynman diagrams with the a_1(1260)pi…
The aim of this work is to give a pedagogical derivation of polarization observables for the annihilation reaction $e^+ + e^- \to N+ \bar N$. The reaction mechanism is one photon + two photon exchange, the last is described by axial…
We examine the dynamics of a baryon number zero lump in the Skyrme picture, as a model for annihilation in the $\bar{N}N$ system. We find that radiation propagates at the causal limit as a localized pulse and that the linearized theory…
We argue that the observed antiproton production in heavy-ion collisions at CERN-SpS energies can be understood if (contrary to most sequential scattering approaches) the backward direction in the process $p\bar p \leftrightarrow…
The thermal multihadron production observed in different high energy collisions poses two basic problems: (1) why do even elementary collisions with comparatively few secondaries (e+e- annihilation) show thermal behaviour, and 2) why is…
The ratio of the B+ B- and B0 B0bar production rates in e+ e- annihilation is computed as a function of the B meson velocity and BB* pi coupling constant, using a non-relativistic effective field theory.
We study the spin-entangled mixed state of a spin-1/2 baryon-antibaryon pair produced in the process e+e- to J/psi, psi(2S) to BBbar. We demonstrate that the spin entanglement of the system can increase following the decays B to b + M and…
We investigate threshold pion photoproduction in the framework of heavy baryon chiral perturbation theory. We give the expansion of the electric dipole amplitude $E_{0+}$ to three orders in $\mu$, the ratio of the pion to nucleon mass, and…
Contrary to the reaction pbar + p --> e+ e- with a high momentum incident antiproton on a free target proton at rest, in which the invariant mass M of the (e+ e-) pair is necessarily much larger than the (pbar p) mass, in the reaction pbar…
We consider the virtual effects of a general type of Anomalous (triple) Gauge Couplings on various experimental observables in the process of electron-positron annihilation into a final fermion-antifermion state. We show that the use of a…
In the framework of quark-hadron duality, the cross section values of charmonium and doubly charmed baryon production in $e^+e^-$-annihilations have been estimated at interaction energy $\sqrt{s}=10.6$ GeV. It has been shown that the…
The s-channel annihilation of proton and antiproton into a neutral pion and a real or virtual photon followed by lepton pair emission is studied. Such mechanism is expected to play a role at moderate values of the total energy $\sqrt{s}$,…
We study the measurement of the quark fragmentation functions for spin-1/2 baryon production ($\Lambda$ and $\bar \Lambda$, in particular) in unpolarized $e^+e^-$ annihilation. The spin-dependent fragmentation functions $\hat g_1(z)$ and…
We show that the behavior of the excitation curves of some $e^+e^-$ annihilation processes close to the nucleon-antinucleon threshold can be explained either by the $\rho(1900)$ resonance itself or by its interference with other resonances.…
The baryon-antibaryon asymmetry (excess of matter over antimatter in our Universe), indicated by observational data from the Cosmic Microwave Background anisotropies, predictions of primordial Nucleosynthesis, and the absence of intense…