Measurement of the production and muonic decay rate ofWandZbosons inpp¯collisions at √s=1.8 TeV

An analysis of proton-antiproton collisions at √s =1.8 TeV recorded with the Collider Detector at Fermilab (CDF) yields σ(pp¯→WX)B(W→μν)=2.21±0.22 nb and σ(pp¯→ZX)B(Z →${\mathrm{\mu }}^{+}$ ${\mathrm{\mu }}^{\mathrm{-})}$=0.226±0.032 nb. The ratio is ${\mathit{R}}_{\mathrm{\mu }}$=${\mathrm{\sigma }}_{\mathit{W}}$B(W→μν)/${\mathrm{\sigma }}_{\mathit{Z}}$B(Z→${\mathrm{\mu }}^{+}$ ${\mathrm{\mu }}^{\mathrm{-}}$)=9.8±1.2. Combining with previous CDF electron results gives ${\mathrm{\sigma }}_{\mathit{W}}$B(W→lν)=2.20±0.20 nb, ${\mathrm{\sigma }}_{\mathit{Z}}$B(Z→${\mathit{l}}^{+}$ ${\mathit{l}}^{\mathrm{-}}$)=0.214±0.023 nb, and ${\mathit{R}}_{\mathit{l}}$=10.0±0.8. We extract the ratios of the coupling constants ${\mathit{g}}_{\mathrm{\mu }}$/${\mathit{g}}_{\mathit{e}}$ and ${\mathit{g}}_{\mathrm{\tau }}$/${\mathit{g}}_{\mathrm{\mu }}$. Using standard model assumptions we deduce the inverse branching ratio ${\mathit{B}}^{\mathrm{-}1}$(W→lν), the width Γ(W), and a decay-mode-independent lower bound on the top quark mass of 45 GeV/${\mathit{c}}^2$ (95% C.L.).