F. Abe et al., OBSERVATION OF LAMBDA(B)(0)-]J PSI-LAMBDA AT THE FERMILAB PROTON-ANTIPROTON COLLIDER/, Physical review. D. Particles and fields, 55(3), 1997, pp. 1142-1152
The decay Lambda(b)(0) --> J/psi Lambda is observed in 110 pb(-1) of p
(p) over bar collisions taken at root s = 1.8 TeV. These data are use
d to measure a Lambda(b)(0) mass of 5621+/-4(stat)+/-3(syst) MeV/c(2),
and a mass difference between the Lambda(b)(0) and the B-0 of 340+/-5
(stat)+/-1(syst) MeV/c(2). The production cross-section times branchin
g fraction for the decay Lambda(b)(0) --> J/psi Lambda relative to tha
t for the decay B-0 --> J/psi K-S(0) has been measured to be 0.27+/-0.
12(stat)+/-0.05(syst).