Measurement of the CKM angle γ and Bs0-B<overbar></mml:mover>s0 mixing frequency with Bs0→Ds?h±π±π<mml:mo>? decays

作者：Aaij, R.; Beteta, C. Abellan; Adeva, B.; Adinolfi, M.; Aidala, C. A.; Ajaltouni, Z.; Akar, S.; Albicocco, P.; Albrecht, J.; Alessio, F.; Alexander, M.; Albero, A. Alfonso; Alkhazov, G.; Cartelle, P. Alvarez; Alves, A. A., Jr.; Amato, S.; Amerio, S.; Amhis, Y.; An, L.; Anderlini, L.; Andreassi, G.; Andreotti, M.; Andrews, J. E.; Archilli, F.; d'Argent, P.; Romeu, J. Arnau; Artamonov, A.; Artuso, M.; Arzymatov, K.; Aslanides, E.; Atzeni, M.; Audurier, B.; Bachmann, S.; Back, J. J.; Baker, S.

来源：JOURNAL OF HIGH ENERGY PHYSICS, 2021, (3): 137.

DOI：10.1007/JHEP03(2021)137

• B physics
• CKM angle gamma
• CP violation
• Hadron-Hadron scattering (experiments)
• Oscillation

The CKM angle gamma is measured for the first time from mixing-induced CP violation between Bs0 -> Ds -/+ K pi +/- pi -/+ and B<overbar></mml:mover>s0 -> Ds +/- K -/+ pi -/+ pi +/- decays reconstructed in proton-proton collision data corresponding to an integrated luminosity of 9 fb(-1) recorded with the LHCb detector. A time-dependent amplitude analysis is performed to extract the CP-violating weak phase gamma - 2 beta (s) and, subsequently, gamma by taking the Bs0-B<overbar></mml:mover>s0 mixing phase beta (s) as an external input. The measurement yields gamma = (44 +/- 12)degrees modulo 180 degrees, where statistical and systematic uncertainties are combined. An alternative model-independent measurement, integrating over the five-dimensional phase space of the decay, yields gamma=<mml:mfenced close=")" open="(">44-13+20</mml:mfenced>degrees modulo 180 degrees. Moreover, the Bs0-B<overbar></mml:mover>s0 oscillation frequency is measured from the flavour-specific control channel Bs0 -> Ds-pi <mml:mo>+pi <mml:mo>+pi <mml:mo>- to be m(s) = (17.757 +/- 0.007(stat) +/- 0.008(syst)) ps(-1), consistent with and more precise than the current world-average value.<fig id="Figa" position="anchor"><graphic position="anchor" specific-use="HTML" mime-subtype="JPEG" xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="MediaObjects/13130_2021_15094_Figa_HTML.jpg" id="MO1"></graphic