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arXiv · 1903.05530

Measurement of the $CP$-violating phase $ϕ_s$ from $B_{s}^{0}\to J/ψπ^+π^-$ decays in 13 TeV $pp$ collisions

LHCb Collaboration·R. Aaij·C. Abellán Beteta·B. Adeva·M. Adinolfi·C. A. Aidala·Z. Ajaltouni·S. Akar·P. Albicocco·J. Albrecht·F. Alessio·M. Alexander·A. Alfonso Albero·G. Alkhazov·P. Alvarez Cartelle·A. A. Alves Jr·S. Amato·Y. Amhis·L. An·L. Anderlini·G. Andreassi·M. Andreotti·J. E. Andrews·F. Archilli·J. Arnau Romeu·A. Artamonov·M. Artuso·K. Arzymatov·E. Aslanides·M. Atzeni·B. Audurier·S. Bachmann·J. J. Back·S. Baker·V. Balagura·W. Baldini·A. Baranov·R. J. Barlow·G. C. Barrand·S. Barsuk·W. Barter·M. Bartolini·F. Baryshnikov·V. Batozskaya·B. Batsukh·A. Battig·V. Battista·A. Bay·F. Bedeschi·I. Bediaga·A. Beiter·L. J. Bel·S. Belin·N. Beliy·V. Bellee·N. Belloli·K. Belous·I. Belyaev·G. Bencivenni·E. Ben-Haim·S. Benson·S. Beranek·A. Berezhnoy·R. Bernet·D. Berninghoff·E. Bertholet·A. Bertolin·C. Betancourt·F. Betti·M. O. Bettler·Ia. Bezshyiko·S. Bhasin·J. Bhom·M. S. Bieker·S. Bifani·P. Billoir·A. Birnkraut·A. Bizzeti·M. Bjørn·M. P. Blago·T. Blake·F. Blanc·S. Blusk·D. Bobulska·V. Bocci·O. Boente Garcia·T. Boettcher·A. Bondar·N. Bondar·S. Borghi·M. Borisyak·M. Borsato·M. Boubdir·T. J. V. Bowcock·C. Bozzi·S. Braun·M. Brodski·J. Brodzicka·A. Brossa Gonzalo·D. Brundu
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Abstract

Decays of $B_{s}^{0}$ and $\overline{B}{}_{s}^{0}$ mesons into $J/ψπ^+π^-$ final states are studied in a data sample corresponding to 1.9 fb$^{-1}$ of integrated luminosity collected with the LHCb detector in 13 TeV $pp$ collisions. A time-dependent amplitude analysis is used to determine the final-state resonance contributions, the $CP$-violating phase $ϕ_s=-0.057\pm 0.060\pm 0.011$ rad, the decay-width difference between the heavier mass $B_{s}^{0}$ eigenstate and the $B^{0}$ meson of $-0.050\pm 0.004\pm 0.004$ ps$^{-1}$, and the $CP$-violating parameter $|λ|=1.01_{-0.06}^{+0.08}\pm0.03$, where the first uncertainty is statistical and the second systematic. These results are combined with previous LHCb measurements in the same decay channel using 7 TeV and 8 TeV $pp$ collisions obtaining $ϕ_s =0.002\pm0.044\pm0.012$ rad, and $|λ| =0.949\pm0.036\pm0.019$.

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LHCb Collaboration, R. Aaij, C. Abellán Beteta, B. Adeva, M. Adinolfi, C. A. Aidala, Z. Ajaltouni, S. Akar, P. Albicocco, J. Albrecht, F. Alessio, M. Alexander, A. Alfonso Albero, G. Alkhazov, P. Alvarez Cartelle, A. A. Alves Jr, S. Amato, Y. Amhis, L. An, L. Anderlini, G. Andreassi, M. Andreotti, J. E. Andrews, F. Archilli, J. Arnau Romeu, A. Artamonov, M. Artuso, K. Arzymatov, E. Aslanides, M. Atzeni, B. Audurier, S. Bachmann, J. J. Back, S. Baker, V. Balagura, W. Baldini, A. Baranov, R. J. Barlow, G. C. Barrand, S. Barsuk, W. Barter, M. Bartolini, F. Baryshnikov, V. Batozskaya, B. Batsukh, A. Battig, V. Battista, A. Bay, F. Bedeschi, I. Bediaga, A. Beiter, L. J. Bel, S. Belin, N. Beliy, V. Bellee, N. Belloli, K. Belous, I. Belyaev, G. Bencivenni, E. Ben-Haim, S. Benson, S. Beranek, A. Berezhnoy, R. Bernet, D. Berninghoff, E. Bertholet, A. Bertolin, C. Betancourt, F. Betti, M. O. Bettler, Ia. Bezshyiko, S. Bhasin, J. Bhom, M. S. Bieker, S. Bifani, P. Billoir, A. Birnkraut, A. Bizzeti, M. Bjørn, M. P. Blago, T. Blake, F. Blanc, S. Blusk, D. Bobulska, V. Bocci, O. Boente Garcia, T. Boettcher, A. Bondar, N. Bondar, S. Borghi, M. Borisyak, M. Borsato, M. Boubdir, T. J. V. Bowcock, C. Bozzi, S. Braun, M. Brodski, J. Brodzicka, A. Brossa Gonzalo, D. Brundu. 2019-08-06. Measurement of the $CP$-violating phase $ϕ_s$ from $B_{s}^{0}\to J/ψπ^+π^-$ decays in 13 TeV $pp$ collisions. https://doi.org/10.1016/j.physletb.2019.07.036

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