A search for rare charmlessdecays of Bd0 and Bs0 mesons has been performed in the exclusive channels Bd(s)0 →ηη, Bd(s)0 →ηπ0 and Bd(s)0 →π0π0. The data sample consisted of three million hadronic Z decays collected by the L3 experiment at LEP from 1991 through 1994. No candidate event has been observed and the following upper limits at 90% confidence level on the branching ratios have been set: Br(B()d→ηη) <4.1 x 10−4, Br(B()s→ηη) < 1.5 x 10−3, Br(B()d→ηφ()) < 2.5 x 10−4, Br(B()s→ηphi;()) < 1.0 x 10−3, Br(B()d→phi;()phi;()) < 6.0 x 10−5, Br(B()s→phi;()phi;()) < 2.1 x 10−4. These are the first experimental limits on Bd0→ηη and on the Bs0neutralcharmless modes.
Search for Neutral Charmless B Decays at LEP
CAVALLO, Nicola;
1995-01-01
Abstract
A search for rare charmlessdecays of Bd0 and Bs0 mesons has been performed in the exclusive channels Bd(s)0 →ηη, Bd(s)0 →ηπ0 and Bd(s)0 →π0π0. The data sample consisted of three million hadronic Z decays collected by the L3 experiment at LEP from 1991 through 1994. No candidate event has been observed and the following upper limits at 90% confidence level on the branching ratios have been set: Br(B()d→ηη) <4.1 x 10−4, Br(B()s→ηη) < 1.5 x 10−3, Br(B()d→ηφ()) < 2.5 x 10−4, Br(B()s→ηphi;()) < 1.0 x 10−3, Br(B()d→phi;()phi;()) < 6.0 x 10−5, Br(B()s→phi;()phi;()) < 2.1 x 10−4. These are the first experimental limits on Bd0→ηη and on the Bs0neutralcharmless modes.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
