Measurement of BB angular correlations based on secondary vertex reconstruction at √s=7  TeV

Frédéric J. Ronga, Marie-Christine Sawley, Sergio Cittolin, Leonardo Sala, Carmelo Marchica, Andrea Rizzi, Alessandro Thea, Francesca Nessi-Tedaldi, Christoph Grab, Filip Moortgat, Benjamin Stieger, Alain Hervé, Jürg Eugster, Lukas Wehrli, Klaus Freudenreich, Michael Dittmar, Pablo Martinez Ruiz Del Arbol, Pascal Nef, Werner Lustermann, Günther Dissertori, Lea Caminada, Ann-Karin Sanchez, Marco Rossini, Konstantinos Theofilatos, Joanna Weng … & Matthias Weber
A measurement of the angular correlations between beauty and anti-beauty hadrons (BB¯¯¯¯) produced in pp collisions at a centre-of-mass energy of 7 TeV at the CERN LHC is presented, probing for the first time the region of small angular separation. The B hadrons are identified by the presence of displaced secondary vertices from their decays. The B hadron angular separation is reconstructed from the decay vertices and the primary-interaction vertex. The differential BB¯¯¯¯ production cross...