a Search for the Short-Lived B Meson in UPSILON(5S) Decays
Abstract
We have examined a data set consisting of 135 pb^{-1} of integrated luminosity taken on the Upsilon(5S) with the CLEO detector in search of evidence for B _{s} meson production. The search is conducted by comparing the products Upsilon (5S) decays with those of Upsilon (4S) which is known to decay mostly to B ^0B^0 and B ^-B^+. We attempt to exploit the expected differences between the B _{s} and B^0, namely mass and constituent quark content. The inclusive lepton spectrum from Upsilon(5S) decays is fit to determine if it is more consistent with having resulted from the decays of B_{s } mesons or with B^0 and B^+ mesons. At 90% C.L. we find a lower limit of 38 or 39% of Upsilon (5S)decays are to B_{s} meson pairs depending on the model of semileptonic decay used, assuming a B_{s} mass around 5.37 GeV, and assuming that the Upsilon (5S) decays to b-flavored meson pairs all the time. The inclusive yields of K^+, K ^0, phi, D ^0, and D_{s} mesons (and charge conjugates) on the Upsilon (5S) and Upsilon(4S) were compared. The differences between the two when interpreted as the result of B_{s} meson decays at the Upsilon(5S) yields a measurement of 0.40 +/- 0.39 as the fraction of Upsilon(5S) decays that produce B_{s} meson pairs. A search for exclusive hadronic B_ {s} decays was conducted and a few candidate events near a mass of 5.395 GeV were found.
- Publication:
-
Ph.D. Thesis
- Pub Date:
- 1991
- Bibcode:
- 1991PhDT........24N
- Keywords:
-
- UPSILON(5S) DECAYS;
- B(S) MESONS;
- Physics: Elementary Particles and High Energy