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arXiv · 1207.5993

Measurement of the effective $B_s^0 \rightarrow K^+ K^-$ lifetime

LHCb collaboration·R. Aaij·C. Abellan Beteta·A. Adametz·B. Adeva·M. Adinolfi·C. Adrover·A. Affolder·Z. Ajaltouni·J. Albrecht·F. Alessio·M. Alexander·S. Ali·G. Alkhazov·P. Alvarez Cartelle·A. A. Alves Jr·S. Amato·Y. Amhis·J. Anderson·R. B. Appleby·O. Aquines Gutierrez·F. Archilli·A. Artamonov·M. Artuso·E. Aslanides·G. Auriemma·S. Bachmann·J. J. Back·V. Balagura·W. Baldini·R. J. Barlow·C. Barschel·S. Barsuk·W. Barter·A. Bates·C. Bauer·Th. Bauer·A. Bay·J. Beddow·I. Bediaga·S. Belogurov·K. Belous·I. Belyaev·E. Ben-Haim·M. Benayoun·G. Bencivenni·S. Benson·J. Benton·R. Bernet·M. -O. Bettler·M. van Beuzekom·A. Bien·S. Bifani·T. Bird·A. Bizzeti·P. M. Bjørnstad·T. Blake·F. Blanc·C. Blanks·J. Blouw·S. Blusk·A. Bobrov·V. Bocci·A. Bondar·N. Bondar·W. Bonivento·S. Borghi·A. Borgia·T. J. V. Bowcock·C. Bozzi·T. Brambach·J. van den Brand·J. Bressieux·D. Brett·M. Britsch·T. Britton·N. H. Brook·H. Brown·A. Büchler-Germann·I. Burducea·A. Bursche·J. Buytaert·S. Cadeddu·O. Callot·M. Calvi·M. Calvo Gomez·A. Camboni·P. Campana·A. Carbone·G. Carboni·R. Cardinale·A. Cardini·L. Carson·K. Carvalho Akiba·G. Casse·M. Cattaneo·Ch. Cauet·M. Charles·Ph. Charpentier·P. Chen
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Abstract

A precise determination of the effective $B_s^0 \rightarrow K^+ K^-$ lifetime can be used to constrain contributions from physics beyond the Standard Model in the $B_s^0$ meson system. Conventional approaches select $B$ meson decay products that are significantly displaced from the $B$ meson production vertex. As a consequence, $B$ mesons with low decay times are suppressed, introducing a bias to the decay time spectrum which must be corrected. This analysis uses a technique that explicitly avoids a lifetime bias by using a neural network based trigger and event selection. Using 1.0 fb$^{-1}$ of data recorded by the LHCb experiment, the effective $B_s^0 \rightarrow K^+ K^-$ lifetime is measured as $1.455 \pm 0.046 \; \mathrm{(stat.)} \pm 0.006 \; \mathrm{(syst.)} \, \mathrm{ps}.$

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LHCb collaboration, R. Aaij, C. Abellan Beteta, A. Adametz, B. Adeva, M. Adinolfi, C. Adrover, A. Affolder, Z. Ajaltouni, J. Albrecht, F. Alessio, M. Alexander, S. Ali, G. Alkhazov, P. Alvarez Cartelle, A. A. Alves Jr, S. Amato, Y. Amhis, J. Anderson, R. B. Appleby, O. Aquines Gutierrez, F. Archilli, A. Artamonov, M. Artuso, E. Aslanides, G. Auriemma, S. Bachmann, J. J. Back, V. Balagura, W. Baldini, R. J. Barlow, C. Barschel, S. Barsuk, W. Barter, A. Bates, C. Bauer, Th. Bauer, A. Bay, J. Beddow, I. Bediaga, S. Belogurov, K. Belous, I. Belyaev, E. Ben-Haim, M. Benayoun, G. Bencivenni, S. Benson, J. Benton, R. Bernet, M. -O. Bettler, M. van Beuzekom, A. Bien, S. Bifani, T. Bird, A. Bizzeti, P. M. Bjørnstad, T. Blake, F. Blanc, C. Blanks, J. Blouw, S. Blusk, A. Bobrov, V. Bocci, A. Bondar, N. Bondar, W. Bonivento, S. Borghi, A. Borgia, T. J. V. Bowcock, C. Bozzi, T. Brambach, J. van den Brand, J. Bressieux, D. Brett, M. Britsch, T. Britton, N. H. Brook, H. Brown, A. Büchler-Germann, I. Burducea, A. Bursche, J. Buytaert, S. Cadeddu, O. Callot, M. Calvi, M. Calvo Gomez, A. Camboni, P. Campana, A. Carbone, G. Carboni, R. Cardinale, A. Cardini, L. Carson, K. Carvalho Akiba, G. Casse, M. Cattaneo, Ch. Cauet, M. Charles, Ph. Charpentier, P. Chen. 2012-09-19. Measurement of the effective $B_s^0 \rightarrow K^+ K^-$ lifetime. https://doi.org/10.1016/j.physletb.2012.08.033

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