Production of associated $\hat{I}\yen$ and open charm hadrons in $pp$ collisions at $\sqrt{s}=7$ and $8$TeV via double parton scattering

Abstract

Associated production of bottomonia and open charm hadrons in $pp$ collisions at $\sqrt{s}=7$ and $8$TeV is observed using data corresponding to an integrated luminosity of 3$f{b}^{-1}$ accumulated with the LHCb detector. The observation of five combinations, $\hat{I}\yen (1S)D^0$, $\hat{I}\yen (2S)D^0$, $\hat{I}\yen (1S)D^{+}$, $\hat{I}\yen (2S)D^{+}$ and $\hat{I}\yen (1S)D_s^{+}$, is reported. Production cross-sections are measured for $\hat{I}\yen (1S)D^0$ and $\hat{I}\yen (1S)D^{+}$ pairs in the forward region. The measured cross-sections and the differential distributions indicate the dominance of double parton scattering as the main production mechanism. This allows a precise measurement of the effective cross-section for double parton scattering.

36 pages, 11 figures. All figures and tables, along with any supplementary material and additional information, are available at https://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2015-046.html