Angular distributions in J/ψ→ppˉπ0(η)J/\psi\to p\bar{p}\pi^{0}(\eta) decays

The differential decay rates of the processes $J/\psi\to p\bar{p}\pi^{0}$ and $J/\psi\to p\bar{p}\eta$ close to the $p\bar{p}$ threshold are calculated with the help of the $N\bar{N}$ optical potential. The same calculations are made for the decays of $\psi(2S)$. We use the potential which has been suggested to fit the cross sections of $N\bar{N}$ scattering together with $N\bar{N}$ and six pion production in $e^{+}e^{-}$ annihilation close to the $p\bar{p}$ threshold. The $p\bar{p}$ invariant mass spectra is in agreement with the available experimental data. The anisotropy of the angular distributions, which appears due to the tensor forces in the $N\bar{N}$ interaction, is predicted close to the $p\bar{p}$ threshold. This anisotropy is large enough to be investigated experimentally. Such measurements would allow one to check the accuracy of the model of $N\bar{N}$ interaction.Comment: 10 pages, 8 figure

Non-catalytic bromination of benzene: a combined computational and experimental study

The non-catalytic bromination of benzene is shown experimentally to require high 5-14M concentrations of bromine in order to proceed at ambient temperatures to form predominantly bromobenzene, along with detectable (The non-catalytic bromination of benzene is shown experimentally to require high 5-14M concentrations of bromine in order to proceed at ambient temperatures to form predominantly bromobenzene, along with detectable (The non-catalytic bromination of benzene is shown experimentally to require high 5-14M concentrations of bromine in order to proceed at ambient temperatures to form predominantly bromobenzene, along with detectable

Natural explanation of recent results on e+e−→ΛΛˉe^{+}e^{-}\to\Lambda\bar{\Lambda}

We show that the recent experimental data on the cross section of the process $e^{+}e^{-}\to\Lambda\bar{\Lambda}$ near the threshold can be perfectly explained by the final-state interaction of $\Lambda$ and $\bar{\Lambda}$. The enhancement of the cross section is related to the existence of low-energy real or virtual state in the corresponding potential. We present a simple analytical formula that fits the experimental data very well.Comment: 2 pages, 1 figur

Near-threshold resonance in e+e−→ΛcΛˉce^{+}e^{-}\rightarrow\Lambda_{c}\bar{\Lambda}_{c} process

We discuss the influence of various contributions of the $\Lambda_{c}\bar{\Lambda}_{c}$ potential on the energy dependence of the cross section $e^{+}e^{-}\rightarrow\Lambda_{c}\bar{\Lambda}_{c}$ near the threshold. New BESIII experimental data on the cross section and electromagnetic form factors $G_{E}$ and $G_{M}$ are taken into account. Our predictions are in good agreement with experimental data. We predict a bound state of $\Lambda_{c}\bar{\Lambda}_{c}$ at energy $\sim 38~\textrm{MeV}$ below the threshold that may manifest itself in anomalous behavior of light meson production cross sections in a given energy region.Comment: 5 pages, 1 figur

Bremsstrahlung on noble gases at low energies

A detailed analysis of the bremsstrahlung spectrum at nonrelativistic electron scattering on argon and xenon is carried out. It is shown that the approximate formulas widely used for the description of bremsstrahlung spectra lead to predictions that significantly differ from the exact results. In the limit when the photon frequency tends to zero, a rigorous proof of the relationship between the spectrum of the bremsstrahlung with a transport cross section of electron scattering on an atom is given. This proof does not require any assumptions about the dependence of the scattering phases on energy. For electron energies lower than the luminescence threshold, it is shown that the predictions for a number of radiated photons obtained by the exact formula are in good agreement with the available experimental data.Comment: 15 pages, 5 figures, new section on the angular distributions is adde