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arXiv · 1511.02428

Evidence for simultaneous production of $J/ψ$ and $Υ$ mesons

D0 Collaboration
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Abstract

We report evidence for the simultaneous production of $J/ψ$ and $Υ$ mesons in 8.1 fb$^{-1}$ of data collected at $\sqrt{s}=$1.96 TeV by the D0 experiment at the Fermilab $p \bar p$ Tevatron Collider. Events with these characteristics are expected to be produced predominantly by gluon-gluon interactions. In this analysis, we extract the effective cross section characterizing the initial parton spatial distribution, $σ_{eff}=2.2\pm 0.7\mbox{(stat)} \pm 0.9 \mbox{(syst)} ~\mbox{mb}$.

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D0 Collaboration. 2016-02-26. Evidence for simultaneous production of $J/ψ$ and $Υ$ mesons. https://doi.org/10.1103/physrevlett.116.082002

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