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We calculate the rate of production ofW+Υ and Z0+Υ at the Tevatron. We find the cross sections at a center-of-mass energy of 1.8 TeV to be roughly 450 pb for W+Υ and 150 pb for Z0+Υ. The dominant production mechanism involves the binding of a color-octet bb̄ pair into a P-wave bottomonium state which subsequently decays into Υ. The purely leptonic decay modes of Υ, W, and Z0 provide signatures w...
The proton-nucleon cross section ratio R = Br(Υ → l+l−) · dσ(Υ)/dy|y=0 /σ(J/ψ) has been measured with the HERA-B spectrometer in fixed-target proton-nucleus collisions at 920 GeV proton beam energy corresponding to a proton-nucleon cms energy of √ s = 41.6 GeV. The combined results for the decay channels Υ → e+e− and Υ → μ+μ− yield a ratio R = (9.0±2.1) ·10−6 . The corresponding Υ production cr...
The ratio R(τμ)(Υ(1S))=Γ(Υ(1S)→τ+ τ-)/Γ(Υ(1S)→μ+ μ-) is measured using a sample of (121.8±1.2)×10(6)Υ(3S) events recorded by the BABAR detector. This measurement is intended as a test of lepton universality and as a search for a possible light pseudoscalar Higgs boson. In the standard model (SM) this ratio is expected to be close to 1. Any significant deviations would violate lepton universalit...
We calculate the rate of production of W + Υ and Z0 + Υ in hadron colliders. We find the cross sections for W + Υ and Z0 + Υ to be roughly 0.45 pb and 0.15 pb at the Tevatron and roughly 4 pb and 2 pb at the LHC. The dominant production mechanism involves the binding of a color-octet bb̄ pair into a P-wave bottomonium state which subsequently decays into Υ. The purely leptonic decay modes of Υ, ...
The production of Υ (1S), Υ (2S) and Υ (3S) mesons in proton-proton collisions at the centre-of-mass energy of √ s = 7 TeV is studied with the LHCb detector. The analysis is based on a data sample of 25 pb −1 collected at the Large Hadron Collider. The Υ mesons are reconstructed in the decay mode Υ → μ + μ − and the signal yields are extracted from a fit to the μ + μ − invariant mass distributi...
Assuming the QCD multipole expansion is applicable to hadronic transitions of Υ(3S) into lower level bottomonia, we consider the possibility that Υ(3S) has a D−wave component. This assumption leads to a natural explanation of the ππ spectrum in Υ(3S) → Υ(1S) ππ. Consequences of this assumption on other hadronic and radiative transitions of Υ(3S) are also discussed in the same context. PACS numb...
The polarization of inclusive Υ(nS) at the Fermilab Tevatron is calculated within the nonrelativistic QCD factorization framework. We use a recent determination of the NRQCD matrix elements from fitting the CDF data on bottomonium production from Run IB of the Tevatron. The result for the polarization of Υ(1S) integrated over the transverse momentum bin 8 < pT < 20 GeV is consistent with a rece...
We report the results of a high-statistics search for H dibaryon production in inclusive Υ(1S) and Υ(2S) decays. No indication of an H dibaryon with a mass near the M(H)=2m(Λ) threshold is seen in either the H→Λpπ(-) or ΛΛ decay channels and 90% confidence level branching-fraction upper limits are set that are between one and two orders of magnitude below the measured branching fractions for in...
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