Evidence for Bs Production at the Υ(5s) from Cleo and Properties of the Υ(4s) from Babar
نویسنده
چکیده
The Υ(4S) is the lowest bb̄ resonance above BB̄ threshold. Its mass and total width had been measured in scans of the total ee cross-section at center of mass energy around 10.58 GeV. 1,2,3,4 The Υ(4S) decays into BB andBB̄ modes allowing these particles to be carefully studied. Many B branching fractions had been measured from Υ(4S) data. Most of them, however, based on the assumption of equal production rates of the charged and neutralBB̄ pairs. Previous measurements are consistent with this assumption. 5,6,7,8 More precise measurement may result in renormalization of B decay branching fractions. The Υ(5S) was discovered by measuring the total hadronic cross-section above Υ(4S) as a function of energy at CESR. 1,2 It is massive enough to produce B (∗) s B̄ (∗) s pairs. With limited data samples, experiments failed to clearly show the level of Bs production at the Υ(5S). In this paper I summarize recent studies from BaBar and CLEO on these issues. The results on B(Υ(4S) → BB̄) from BaBar and Bs from CLEO are preliminary.
منابع مشابه
STUDIES OF Bs PRODUCTION AND SEMILEPTONIC DECAY, AND OF ANTIDEUTERON PRODUCTION IN Υ DECAY AND QUARK FRAGMENTATION AT BABAR
Title of dissertation: STUDIES OF Bs PRODUCTION AND SEMILEPTONIC DECAY, AND OF ANTIDEUTERON PRODUCTION IN Υ DECAY AND QUARK FRAGMENTATION AT BABAR Brian Hamilton, Doctor of Philosophy, 2012 Dissertation directed by: Professor Abolhassan Jawahery Department of Physics I present a measurement of the inclusive semileptonic branching fraction of the Bs meson and Bs production rates relative to all ...
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