We present measurements of the branching fractions of eight \overline B{}^0\to D^{(*)+} K^- K^{(*)0}_{(S)}, B^{-}\to D^{(*)0} K^- K^{(*)0}_{(S)} decay channels. The results are based on data from SuperKEKB electron-positron collisions at the \Upsilon(4S) resonance collected with the Belle II detector, corresponding to an integrated luminosity of 362~\text{fb}^{-1}. The event yields are extracted from fits to the distributions of the difference between expected and observed B meson energy, and are efficiency-corrected as a function of m(K^-K^{(*)0}_{(S)}) and m(D^{(*)}K^{(*)0}_{(S)}) in order to avoid dependence on the decay model. These results include the first observation of \overline B{}^0\to D^+K^-K_S^0, B^-\to D^{*0}K^-K_S^0, and \overline B{}^0\to D^{*+}K^-K_S^0 decays and a significant improvement in the precision of the other channels compared to previous measurements. The helicity-angle distributions and the invariant mass distributions of the K^- K^{(*)0}_{(S)} systems are compatible with quasi-two-body decays via a resonant transition with spin-parity J^P=1^- for the K^-K_S^0 systems and J^P= 1^+ for the K^-K^{*0} systems. We also present measurements of the branching fractions of four \overline B{}^0\to D^{(*)+} D_s^-, B^{-}\to D^{(*)0} D_s^- decay channels with a precision compatible to the current world averages.
Measurement of the branching fractions of $ \overline{B} $ \textrightarrow{} D$^{(*)}$K$^{} {K}_{(S)}^{\left(\ast \right)0} $ and $ \overline{B} $ \textrightarrow{} D$^{(*)} {D}_s^{-} $ decays at Belle II
F. Tenchini;
2024-01-01
Abstract
We present measurements of the branching fractions of eight \overline B{}^0\to D^{(*)+} K^- K^{(*)0}_{(S)}, B^{-}\to D^{(*)0} K^- K^{(*)0}_{(S)} decay channels. The results are based on data from SuperKEKB electron-positron collisions at the \Upsilon(4S) resonance collected with the Belle II detector, corresponding to an integrated luminosity of 362~\text{fb}^{-1}. The event yields are extracted from fits to the distributions of the difference between expected and observed B meson energy, and are efficiency-corrected as a function of m(K^-K^{(*)0}_{(S)}) and m(D^{(*)}K^{(*)0}_{(S)}) in order to avoid dependence on the decay model. These results include the first observation of \overline B{}^0\to D^+K^-K_S^0, B^-\to D^{*0}K^-K_S^0, and \overline B{}^0\to D^{*+}K^-K_S^0 decays and a significant improvement in the precision of the other channels compared to previous measurements. The helicity-angle distributions and the invariant mass distributions of the K^- K^{(*)0}_{(S)} systems are compatible with quasi-two-body decays via a resonant transition with spin-parity J^P=1^- for the K^-K_S^0 systems and J^P= 1^+ for the K^-K^{*0} systems. We also present measurements of the branching fractions of four \overline B{}^0\to D^{(*)+} D_s^-, B^{-}\to D^{(*)0} D_s^- decay channels with a precision compatible to the current world averages.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
