相关论文: Effects of isospin violation in the $e^+e^- \right…
The effects of isotopic invariance violation in the processes $e^{+}e^{-}\to B\bar{B}$, $e^{+}e^{-}\to B^{*}\bar{B}$, and $e^{+}e^{-}\to B^{*}\bar{B}^{*}$ are considered in the energy range between the thresholds of $B^{+}B^{-}$ and…
The subject of the charged-to-neutral yield ratio for B{\bar B} and D{\bar D}pairs near their respective thresholds in e^+e^- annihilation is revisited. As previously argued for the B mesons, this ratio should exhibit a substantial…
It is shown that the ratio of the production rates of the pairs (B+ B-) and (B0 anti-B0) should experience a substantial and rapid variation with energy within the width of the Upsilon(4S) resonance, crossing the value of one near the…
We report the first evidence for isospin violation in $B \to K^* \gamma$ and the first measurement of difference of $CP$ asymmetries between $B^+ \to K^{*+} \gamma$ and $B^0 \to K^{*0} \gamma$. This analysis is based on the data sample…
We revisit the problem of interplay between the strong and the Coulomb interaction in the charged-to-neutral yield ratio for $B {\bar B}$ and $D {\bar D}$ pairs near their respective thresholds in $e^+e^-$ annihilation. We consider here a…
We consider production of overall neutral pairs consisting of heavy $D^{(*)}$ or $B^{(*)}$ meson and antimeson in the processes, where the pair can be created in an $S$-wave, such as $e^+e^- \to \pi^0 \, D^* \bar D^{(*)}$ and $e^+e^- \to…
The cross section of high-energy $e^+e^-$ pair production by a heavy charged particle in the atomic field is investigated in detail. We take into account the interaction with the atomic field of $e^+e^-$ pair and a heavy particle as well.…
We study the effect of isospin degree of freedom on balance energy throughout the mass range between 50 and 350 for two sets of isobaric systems with N/A = 0.5 and 0.58. Our fndings indicate that different values of balance energy for two…
The energy dependence of the cross sections of $p\bar p$, $n\bar n$, and meson production in $e^+e^-$ annihilation in the vicinity of the $p\bar p$ and $n\bar n$ thresholds is studied. The proton-neutron mass difference and the $p\bar p$…
Based on the ultrarelativistic quantum molecular dynamics (UrQMD) model, the effects of the density-dependent symmetry potential for baryons and of the Coulomb potential for produced mesons are investigated for neutron-rich heavy ion…
We present results on the pseudoscalar meson masses from a fully dynamical simulation of QCD+QED. We concentrate particularly on violations of isospin symmetry. We calculate the $\pi^+$-$\pi^0$ splitting and also look at other isospin…
Production cross sections of K$^+$ and K$^-$ mesons have been measured in C+C collisions at beam energies per nucleon below and near the nucleon-nucleon threshold. At a given beam energy, the spectral slopes of the K$^-$ mesons are…
We study the effect of isospin degree of freedom on the balance energy (E$_{bal}$) as well as its mass dependence throughout the mass range 48-270 for two sets of isobaric systems with N/Z = 1 and 1.4 at different colliding geometries…
The integrated cross sections of high-energy $e^+e^-$ electroproduction by an electron in an atomic field is studied. Importance of various contributions to these cross sections is discussed. It is shown that the Coulomb corrections are…
A simple exactly solvable model is proposed for describing the decays $\Upsilon (4S) \rightarrow B^0\bar B^0$ and $\Upsilon (4S) \rightarrow B^+B^-$. Our predictions agree with available experimental data. Using this model, we analyze the…
Strong interactions preserve an approximate isospin symmetry between up ($u$) and down ($d$) quarks, part of the more general flavor symmetry. In the case of $K$ meson production, if this isospin symmetry were exact, it would result in…
We study the effect of isospin degree of freedom on the balance energy (E$_{bal}$) as well as its mass dependence throughout the mass range for two different sets of isobaric systems with N/Z = 1 and 1.4 at different colliding geometries…
We study the effect of isospin degree of freedom on balance energy throughout the mass range between 50 and 350 for two sets of isotopic systems with N/Z = 1.16 and 1.33 as well as isobaric systems with N/Z = 1.0 and 1.4. Our findings…
H.~Yamamoto has proposed employing $B$ mesons produced in conjunction with a single charged pion at an $\Upsilon$ resonance for studies of CP violation in the neutral $B$ meson system at a symmetric $e^+$-$e^-$ collider. The sign of the…
Using the Cottingham formula, we give an estimate of the electromagnetic mass splitting of pseudoscalar heavy mesons in the beauty and charm sector. We include in the dispersion relation the Born term, the $1^-$ resonance and the positive…