We have searched for a heavy neutral gauge boson, Z ′, using the decay channel Z ′ → ee . The data were collected with the DØ detector at the Fermilab Tevatron during the 1992–1993 p p collider run at s =1.8 TeV from an integrated luminosity of 15±1 pb −1 . Limits are set on the cross section times brancing ratio for the process p p → Z′ → ee as a function of the Z ′ mass. We exclude the existence of a Z ′ of mass less than 490 GeV/c 2 , assuming a Z ′ with the same coupling strengths to quarks and leptons as the standard model Z boson.
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This report describes the first search for top squark pair production in the channel stop_1 stopbar_1 -> b bbar chargino_1 chargino_1 -> ee+jets+MEt using 74.9 +- 8.9 pb~-1 of data collected using the D0 detector. A 95% confidence level upper limit on sigma*B is presented. The limit is above the theoretical expectation for sigma*B for this process, but does show the sensitivity of the current D0 data set to a particular topology for new physics.
Data are extracted from the figure. Sigma*Br.
We present a measurement of the cross sections for the associated production of a $W$ boson with at least one heavy quark jet, $b$ or $c$, in proton-antiproton collisions. Data corresponding to an integrated luminosity of 8.7 fb$^{-1}$ recorded with the D0 detector at the Fermilab Tevatron \ppbar Collider at $\sqrt{s}=1.96$ TeV are used to measure the cross sections differentially as a function of the jet transverse momenta in the range 20 to 150 GeV. These results are compared to calculations of perturbative QCD theory as well as predictions from Monte Carlo generators.
The $W + b$-jet production cross sections times $W \to \mu\nu$ branching fraction, ${\rm d}\sigma/{\rm d}p_T^{\rm jet}$.
The $W + c$-jet production cross sections times $W \to \mu\nu$ branching fraction, ${\rm d}\sigma/{\rm d}p_T^{\rm jet}$.
The $\sigma(W+c)/\sigma(W+b)$ cross section ratio in bins of $c(b)$-jet $p_T$.
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