Measurement of the production fraction times branching fraction f(b->Λ.sub. b./sub.) . B(Λ.sub. b./sub.->J/ψΛ)

0367879 - FZÚ 2013 RIV US eng J - Journal Article
Abazov, V. M. - Abbott, B. - Acharya, B.S. - Kupčo, Alexander - Lokajíček, Miloš … Total 421 authors
Measurement of the production fraction times branching fraction f(b->Λ _b) . B(Λ _b->J/ψΛ).
Physical Review D: Particles, Fields, Gravitation and Cosmology. Roč. 84, č. 3 (2011), "031102-1"-"031102-7". ISSN 1550-7998
R&D Projects: GA MŠMT LA08047
Institutional research plan: CEZ:AV0Z10100502
Keywords : D0 * Tevatron * Lambda/b⁰ * bottom * B⁰
Subject RIV: BF - Elementary Particles and High Energy Physics
Impact factor: 4.558, year: 2011

The Lambda(b)(udb) baryon is observed in the decay Lambda(b) -> J/psi Lambda using 6.1fb(-1) of p (p) over bar collisions collected with the D0 detector at root s = 1/96 TeV. The production fraction multiplied by the branching fraction for this decay relative to that for the decay B(0) -> J/psi K(s)(0) is measured to be 0.345 +/- 0.034(stat) +/- 0.033(syst) +/- 0.003(PDG). Using the world average value of f(b -> B(0)) . B(B(0) -> J/psi K(s)(0) = (1.74 +/- 0.08) x 10(-5), we obtain f(b -> Lambda(b)) . B(Lambda(b) -> J/psi Lambda) = (6.01 +/- 0.60(stat) +/- 0.58(syst) +/- 0.28(PDG)) x 10(-5). This measurement represents an improvement in precision by about a factor of 3 with respect to the current world average.
Permanent Link: http://hdl.handle.net/11104/0202400