NUK - logo
E-viri
Celotno besedilo
Odprti dostop
  • Measurement of branching fractions and direct $CP$ asymmetries for $B \to K\pi$ and $B\to\pi\pi$ decays at Belle II
    Adachi, I; Aloisio, A; Asner, D. M; Aushev, V; Bahinipati, S; Becker, J; Behera, P. K; Bertemes, M; Bilka, T; Bobrov, A; Bondar, A; Bračko, M; Branchini, P; Bussino, S; Campajola, M; Chang, M. -C; Cho, S. -J; Choi, S. -K; Choudhury, S; Cremaldi, L. M; Das, S; De Pietro, G; Dhamija, R; Di Capua, F; Dingfelder, J; Dossett, D; Dubey, S; Ecker, P; Epifanov, D; Ferlewicz, D; Finck, C; Finocchiaro, G; Frey, A; Fulsom, B. G; Gaur, V; Giordano, R; Grammatico, T; Gudkova, K; Iijima, T; Inami, K; Ishikawa, A; Itoh, R; Iwasaki, M; Jang, E. -J; Ji, Q. P; Junkerkalefeld, H; Kim, D. Y; Koga, T; Kunigo, T; Kwon, Y. -J; Lai, Y. -T; Lewis, P. M; Libby, J; Maiti, R; Marcantonio, D; Martellini, C; Matsuoka, K; Metzner, F; Moneta, S; Mussa, R; Natkaniec, Z; Natochii, A; Nayak, M; Nazaryan, G; Ogawa, S; Pakhlova, G; Panta, A; Park, S. -H; Paschen, B; Patra, S; Prim, M. T; Roney, J. M; Russo, G; Savinov, V; Shtol, D; Simon, F; Singh, J. B; Soffer, A; Stavroulakis, P; Stroili, R; Tamponi, U; Tittel, O; Trabelsi, K; Unger, K; Unno, Y; Uno, K; Vahsen, S. E; van Tonder, R; Wakai, M; Wakeling, H. M; Watanabe, M; Welsch, M; Won, E; Yan, W; Yelton, J; Yoshihara, K; Yuan, C. Z; Zani, L; Zhou, J. S; Zhukova, V. I

    10/2023
    Journal Article

    Phys. Rev. D 109, 012001 (2024) We report measurements of the branching fractions and direct $\it{CP}$ asymmetries of the decays $B^0 \to K^+ \pi^-$, $B^+ \to K^+ \pi^0$, $B^+ \to K^0 \pi^+$, and $B^0 \to K^0 \pi^0$, and use these for testing the standard model through an isospin-based sum rule. In addition, we measure the branching fraction and direct $\it{CP}$ asymmetry of the decay $B^+ \to \pi^+\pi^0$ and the branching fraction of the decay $B^0 \to \pi^+\pi^-$. The data are collected with the Belle II detector from $e^+e^-$ collisions at the $\Upsilon(4S)$ resonance produced by the SuperKEKB asymmetric-energy collider and contain $387\times 10^6$ bottom-antibottom meson pairs. Signal yields are determined in two-dimensional fits to background-discriminating variables, and range from 500 to 3900 decays, depending on the channel. We obtain $-0.03 \pm 0.13 \pm 0.04$ for the sum rule, in agreement with the standard model expectation of zero and with a precision comparable to the best existing determinations.

Vnos na polico