@article{10902/28406, year = {2011}, month = {3}, url = {https://hdl.handle.net/10902/28406}, abstract = {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 section, measured from a data sample collected by CMS and corresponding to an integrated luminosity of 3.1 pb−1, shows that a sizable fraction of the BB¯¯¯¯ pairs are produced with small opening angles. These studies provide a test of QCD and further insight into the dynamics of bb¯¯¯ production.}, organization = {We wish to congratulate our colleagues in the CERN accelerator departments for the excellent performance of the LHC machine. We thank the technical and administrative staff at CERN and other CMS institutes, and acknowledge support from: FMSR (Austria); FNRS and FWO (Belgium); CNPq, CAPES, FAPERJ, and FAPESP (Brazil); MES (Bulgaria); CERN; CAS, MoST, and NSFC (China); COLCIENCIAS (Colombia); MSES (Croatia); RPF (Cyprus); Academy of Sciences and NICPB (Estonia); Academy of Finland,ME, andHIP (Finland); CEAand CNRS/IN2P3 (France); BMBF, DFG, and HGF (Germany); GSRT (Greece); OTKA and NKTH (Hungary); DAE and DST (India); IPM (Iran); SFI (Ireland); INFN (Italy); NRF and WCU (Korea); LAS (Lithuania); CINVESTAV, CONACYT, SEP, and UASLP-FAI (Mexico); PAEC (Pakistan); SCSR (Poland); FCT (Portugal); JINR (Armenia, Belarus, Georgia, Ukraine, Uzbekistan); MST and MAE (Russia); MSTD (Serbia); MICINN and CPAN (Spain); Swiss Funding Agencies (Switzerland); NSC (Taipei); TUBITAK and TAEK (Turkey); STFC (United Kingdom); DOE and NSF (USA).}, publisher = {Springer Verlag}, publisher = {Journal of High Energy Physics, 2011, 2011(3), 136}, title = {Measurement of BB¯¯¯¯ angular correlations based on secondary vertex reconstruction at s√=7TeV}, author = {Khachatryan, V. and Brochero Cifuentes, Javier Andrés and Cabrillo Bartolomé, José Iban and Calderón Tazón, Alicia and Chamizo Llatas, María and Chuang, S. H. and Duarte Campderros, Jorge and Felcini, Marta and Fernández García, Marcos and Gómez Gramuglio, Gervasio and González Sánchez, Francisco Javier and Jordá Lope, Clara and Lobelle Pardo, Patricia and López Virto, María Amparo and Marco de Lucas, Jesús and Marco de Lucas, Rafael José and Martínez Rivero, Celso and Matorras Weinig, Francisco and Muñoz Sánchez, Francisca Javiela and Piedra Gómez, Jonatan and Rodrigo Anoro, Teresa and Ruiz Jimeno, Alberto and Scodellaro, Luca and Sobrón Sañudo, Mar and Vila Álvarez, Iván and Vilar Cortabitarte, Rocío}, }