Evidence for simultaneous production of $J/\psi$ and ${\rm Y}$ mesons

D0 Collaboration

We report evidence for the simultaneous production of $J/\psi$ and ${\rm Y}$ mesons in 8.1 fb${}^{-1}$ of data collected at $\sqrt{s}=$1.96 TeV by the D0 experiment at the Fermilab $p\bar{p}$…