Search for Associated Production of ${\rm Y}$ and Vector Boson in $p\overline{p}$ Collisions at $\sqrt{s}=1.8\mathrm{T}\mathrm{e}\mathrm{V}$

We present a search for associated production of the ${\rm Y}(1S)$ and a vector boson in $83{\mathrm{p}\mathrm{b}}^{-1}$ of $p\overline{p}$ collisions at $\sqrt{s}=1.8\mathrm{T}\mathrm{e}\mathrm{V}$ collected by the CDF experiment in 1994–1995. We find no evidence of the searched signal in the data, and set upper limits to the production cross sections.

Figure 1

Invariant mass of the two opposite-charge muons before (inset) and after (full-scale histogram) the selection of good muon pairs described in the text.

Figure 2

Transverse momentum of background-subtracted ${\rm Y}(1S)$ candidates in the data (full circles) compared to ${\rm Y}(1S)$ mesons from the SM simulation of ${\rm Y}(1S)W^{\pm }$ and ${\rm Y}(1S)Z^0$ production (empty triangles and squares), with arbitrary normalization.

Figure 3

Invariant mass of the two muons for events selected in the four search channels; the region within vertical lines defines ${\rm Y}(1S)W^{\pm }/{\rm Y}(1S)Z^0$ candidates. The distribution of all dimuon candidates before the vector boson selection is overlaid.