Effects of isospin violation in the $e^{+}{e}^{-}\to B^{(\ast )}{\bar{B}}^{(\ast )}$ cross sections

Abstract

Model estimates are obtained for the influence of Coulomb effects on the ratio of the cross sections for the production of charged and neutral $B\bar{B}$ and $B^{\ast }{\bar{B}}^{\ast }$ pairs in $e^{+}{e}^{-}$ annihilation. It is shown that the difference between the masses of charged and neutral mesons obtained under the assumption that this ratio is constant on a scale of the order of the beam energy spread can differ from the true one by $δM \sim 0.03\,\mbox{MeV}$ at the energy of ${\rm Y}(5S)$ and by $δM \sim 0.4\,\mbox{MeV}$ at the energy of ${\rm Y}(4S)$. Thus, the errors given in the PDG for the difference between the masses of charged and neutral $B$ mesons, based on the results obtained at the energy of ${\rm Y}(4S)$, are strongly underestimated. Similar measurements at the energy of ${\rm Y}(5S)$ will have an order of magnitude smaller systematic shift for the mass difference. This circumstance should be taken into account when planning future experiments at the $B$ factory in KEK.

arXiv comment6 pages, 2 figures

References in corpus (8)

• ON THE COVARIANTIZATION OF THE CHIRAL CONSTRAINT
• Variation of the relative yield of charged and neutral B mesons across the Upsilon(4S) resonance
• Hadronic cross section of $e^{+}{e}^{-}$ annihilation at bottomonium energy region
• Isospin violation in e+ e- --> B Bbar
• Real and virtual $N\bar{N}$ pair production near the threshold
• Isoscalar amplitude dominance in $e^{+}e-$ annihilation to $N\bar{N}$ pair close to the threshold
• Relative yield of charged and neutral heavy meson pairs in e^+ e^- annihilation near threshold
• Coulomb effects in the decays ${\rm Y}(4S)\to B\bar{B}$

Cited by in corpus (2)

• Coupled channels and production of near-threshold $B^{(\ast )}{\bar{B}}^{(\ast )}$ resonances in $e^{+}{e}^{-}$ annihilation
• Charge asymmetry in $e^{+}{e}^{-}\to B^{(\ast )}{\bar{B}}^{(\ast )}$ processes in the vicinity of ${\rm Y}(4S)$