A search for charmless dihadron decays of neutral b-hadrons

A search for charmless dihadron decays of neutral b-hadrons was performed using data obtained from 800 GeV/c proton-gold interactions. The following upper limits on the b-hadron branching ratios (including charge conjugates) were obtained at the 90% confidence limit: Br(Bs → K+K-) + rs x Br(Bd → π+π-) < 2.0 x 10-3; Br(Bd → K+K-) < 9.5 x 10-4; Br(Bs →π+π-) < 2.0 x 10-3; Br(Bd → K+π-) < 1.9 x 10-3; Br(Bs → K-π+) < 2.2 x 10-3; Br(Bd → p bar p) < 1.6 x 10-3; Br(Bs → p bar p) < 9.0 x 10-3; Br(Λd → K+p-) < 6.1 x 10-3; Br(Λb → π+p-) < 9.7 x 10-3; where rs was determined to be 2.9 ± 0.8. These limits assume that Bd/Bs/Λb hadrons are produced in proton on nucleon interactions in the ratio (38 ± 5.7) : (13 ± 3.2) : (9.6 ± 1.7) and that the branching ratio for the cascade decay b-hadron → J/ψ + X → μ+μ- + X is (6.97 ± .64) x 10-4