Measurement of the CKM angle γ and Bs0‐B¯s0 mixing frequency with Bs0→Ds∓h±π±π∓ decays

Autor: Aaij, R, Abellán Beteta, C, Ackernley, T, Adeva, B, Adinolfi, M, Afsharnia, H, Aidala, CA, Aiola, S, Ajaltouni, Z, Akar, S, Albrecht, J, Alessio, F, Alexander, M, Alfonso Albero, A, Aliouche, Z, Alkhazov, G, Alvarez Cartelle, P, Amato, S, Amhis, Y, An, L, Anderlini, L, Andreianov, A, Andreotti, M, Archilli, F, Artamonov, A, Artuso, M, Arzymatov, K, Aslanides, E, Atzeni, M, Audurier, B, Bachmann, S, Bachmayer, M, Back, JJ, Baker, S, Baladron Rodriguez, P, Balagura, V, Baldini, W, Baptista Leite, J, Barlow, RJ, Barsuk, S, Barter, W, Bartolini, M, Baryshnikov, F, Basels, JM, Bassi, G, Batsukh, B, Battig, A, Bay, A, Becker, M, Bedeschi, F, Bediaga, I, Beiter, A, Belavin, V, Belin, S, Bellee, V, Belous, K, Belov, I, Belyaev, I, Bencivenni, G, Ben-Haim, E, Berezhnoy, A, Bernet, R, Berninghoff, D, Bernstein, HC, Bertella, C, Bertholet, E, Bertolin, A, Betancourt, C, Betti, F, Bettler, MO, Bezshyiko, I, Bhasin, S, Bhom, J, Bian, L, Bieker, MS, Bifani, S, Billoir, P, Birch, M, Bishop, FCR, Bizzeti, A, Bjørn, M, Blago, MP, Blake, T, Blanc, F, Blusk, S, Bobulska, D, Boelhauve, JA, Boente Garcia, O, Boettcher, T, Boldyrev, A, Bondar, A, Bondar, N, Borghi, S, Borisyak, M, Borsato, M, Borsuk, JT, Bouchiba, SA, Bowcock, TJV, Boyer, A, Bozzi, C
Přispěvatelé: Alvarez Cartelle, Paula [0000-0003-1652-2834], Apollo - University of Cambridge Repository
Rok vydání: 2021
Předmět:
Popis: The CKM angle $\gamma$ is measured for the first time from mixing-induced $CP$ violation between $B^0_s \rightarrow D_s^\mp K^\pm \pi^\pm \pi^\mp$ and $\bar{B}^0_s \rightarrow D_s^\pm K^\mp \pi^\mp \pi^\pm$ decays reconstructed in proton-proton collision data corresponding to an integrated luminosity of 9 ${\rm fb}^{-1}$ 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 $B^0_s$-$\bar{B}^0_s$ mixing phase $\beta_{s}$ as an external input. The measurement yields $\gamma = (44 \pm 12)^\circ$ modulo $180^\circ$, where statistical and systematic uncertainties are combined. An alternative model-independent measurement, integrating over the five-dimensional phase space of the decay, yields $\gamma = (44^{\,+\,20}_{\,-\,13})^\circ$ modulo $180^\circ$. Moreover, the $B^0_s$-$\bar{B}^0_s$ oscillation frequency is measured from the flavour-specific control channel $B^0_s \rightarrow D_s^- \pi^+ \pi^+ \pi^-$ to be $\Delta m_s = (17.757 \pm 0.007 \,({\rm stat.}) \pm 0.008 \,({\rm syst.})) \text{ps}^{-1}$, consistent with and more precise than the current world-average value.
Databáze: OpenAIRE