We measure the forward-backward asymmetry in the production of ?0b and ?¯0b baryons as a function of rapidity in pp¯ collisions at √s = 1.96 TeV using 10.4 fb-1 of data collected with the D0 detector at the Fermilab Tevatron collider. The asymmetry is determined by the preference of ?0b or ?¯0b particles to be produced in the direction of the beam protons or antiprotons, respectively. As a result, the measured asymmetry integrated over rapidity y in the range 0.1

We present a search for the heavy-flavor baryons $\Xi_{b}$ (bsd) and $\Omega^{-}_{b}$ in decays $\Xi^{-}_{b}$→ J/[psi]$\Xi^{-}_{b}$ → J/[psi][Lambda][pi]-, J/[psi] → [mu]+ [mu]- and $\Omega^{-}_{b}$ → J/[psi]$\Omega^{-}_{b}$ J/[psi][Lambda] $K^{-}_{b}$, J/[psi] → [mu]+ [mu]- respectively.

Early measurements of a large forward-background asymmetry at the CDF and D0 experiments at Fermilab have generated much recent interest, but were hampered by large uncertainties. We present here a new measurement of the parton level forward-backward asymmetry of pair-produced top quarks, using a high-statistics sample with much improved precision. We study the rapidity, y{sub top}, of the top quark production angle with respect to the incoming parton momentum in both the lab and t{bar t} rest frames. We find the parton-level forward-backward asymmetries to be A{sub fb}{sup p{bar p}} = 0.150 ± 0.050{sup stat} ± 0.024{sup syst} A{sub fb}{sup t{bar t}} = 0.158 ± 0.072{sup stat} ± 0.024{sup syst}. These results should be compared with the small p{bar p} frame charge asymmetry expected in QCD at NLO, A{sub fb} = 0.050 ± 0.015. Additionally, we introduce a measurement of the A{sub fb} rapidity dependence dA{sub fb}/d([Delta]y). We find this to be A{sub fb}{sup t{bar t}}).

Current understanding of particle physics postulates that there are 17 fundamental particles that interact via four fundamental forces - gravity, the strong force, the weak force, and the electromagnetic force. These fundamental particles can be classified by their spins into bosons, which are the force-carrying particles with integer spins, and fermions, which have half-integer spins. Fermions can be further divided into quarks and leptons. The particles and three of the four forces - all but gravity - are described by the Standard Model, a local SU(3) x SU(2) x U(1) gauge theory. Electromagnetic and weak interactions as described by Electroweak Theory or Quantum Electrodynamics, SU(2) x U(1). Strong interactions are described by Quantum Chromodynamics or QCD, SU(3). Fermions are grouped into three generations as shown in Table 1.1. Each generation consists of a leptonic doublet containing a charged and a neutral lepton and a weak isospin doublet containing two quarks. The first generation, containing the electron, the electron neutrino, the up quark, and the down quark, is the lightest generation and is thus the most frequently found in nature. The second generation contains the muon, the muon neutrino, the strange quark, and the charm quark. The third generation contains the tau, the tau neutrino, the bottom quark, and the top quark.