We report the observation of the bottom, doubly-strange
Omega-_b through the decay chain Omega-_b --> J/psi Omega-, where
J/psi --> mu+ mu-, Omega- --> Lambda K-, and Lambda --> p pi++,
using 4.2 fb-1 of data from p anti-p collisions at s**(1/2) ñ.96 TeV,
and recorded with the Collider Detector at Fermilab. A signal is
observed whose probability of arising from a background fluctuation is
4.0 x 10-8, or 5.5 Gaussian standard deviations. The Omega-_b mass is
measured to be 6054.4 +/- 6.8(stat.) +/- 0.9(syst.) MeV/c2. The lifetime
of the Omega-_b baryon is measured to be 1.13+0.53_-0.40(stat.) +/-
0.02(syst.) ps. In addition, for the Xi-_b baryon we measure a mass
of 5790.9 +/- 2.6(stat.) +/- 0.8(syst.) MeV/c2 and a lifetime of
1.56+0.27_-0.25(stat.) +/- 0.02(syst.) ps. Under the assumption
that the Xi-_b and Omega-_b are produced with similar kinematic
distributions t the Lambda0(b) baryon, we find sigma(Xi-_b) B(Xi-_b
--> J/psi Xi-)/sigma (Lambda0(b) B(Lambda0(b) --> J/psi Lambda)
0.167{+0.037}_{-0.025}(stat.) and sigma(Omega-_b) B(Omega-_b -->
J/psi Omega-/Sigma(Lambda0(b)) B(Lambda0(b) --> J/psi Lambda)
0.045{+0.017}_{-0.012}(stat.) +/- 0.004(syst.) for baryons produced with
transverse momentum in the range of 6-20 GeV/c.
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Updated: Monday, 2009 October 26 14:01:34 CDT automatically from input from carol picciolo