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arXiv · 1204.5675

Measurement of the CP-violating phase ϕs in Bs->J/ψπ+π- decays

LHCb collaboration·R. Aaij·C. Abellan Beteta·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·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·N. Chiapolini·K. Ciba·X. Cid Vidal
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Abstract

Measurement of the mixing-induced CP-violating phase phi_s in Bs decays is of prime importance in probing new physics. Here 7421 +/- 105 signal events from the dominantly CP-odd final state J/ψpi+ pi- are selected in 1/fb of pp collision data collected at sqrt{s} = 7 TeV with the LHCb detector. A time-dependent fit to the data yields a value of phi_s=-0.019^{+0.173+0.004}_{-0.174-0.003} rad, consistent with the Standard Model expectation. No evidence of direct CP violation is found.

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LHCb collaboration, R. Aaij, C. Abellan Beteta, 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, 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, N. Chiapolini, K. Ciba, X. Cid Vidal. 2012-05-23. Measurement of the CP-violating phase ϕs in Bs->J/ψπ+π- decays. https://doi.org/10.1016/j.physletb.2012.06.032

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