Searches for Λ0 b and Ξ0 b decays to K0 spπ- and K 0 spK- final states with first observation of the Λ0 b → k0 sp7π - decay

Title:	Searches for Λ0 b and Ξ0 b decays to K0 spπ- and K 0 spK- final states with first observation of the Λ0 b → k0 sp7π - decay
Authors:	R, Aaij, B, Adeva M., Adinolfi A, Affolder Z, Ajaltouni ...
Keywords:	B physics;;Branching fraction;Flavor physics;Hadron-hadron scattering
Issue Date:	2014
Publisher:	Journal of High Energy Physics
Citation:	Scopus

URI:	http://link.springer.com/article/10.1007%2FJHEP04%282014%29087 http://repository.vnu.edu.vn/handle/VNU_123/34206

A search for previously unobserved decays of beauty baryons to the final states K0 spπ- and K0 spK- is reported. The analysis is based on a data sample corresponding to an integrated luminosity of 1.0 fb- of pp collisions. The Λ0 b → ̄K pπ- decay is observed with a significance of 8.6σ, with branching fraction (Equation Presented), where the uncertainties are statistical, systematic, from the ratio of fragmentation fractions f Λ 0 b/fd, and from the branching fraction of the B0 → K0π+π - normalisation channel, respectively. A first measurement is made of the CP asymmetry, giving (Equation Presented). No significant signals are seen for Λ0 b → K0 spK - decays, Ξ0 b decays to both the K 0 spπ- and K0 spK - final states, and the Λ0 b → D- s(→ K0 sK-)p decay, and upper limits on their branching fractions are reported.