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تسجيل مستخدم جديدMeasurements of $q^2$ Moments of Inclusive $B rightarrow X_c ell^+ u_{ell}$ Decays with Hadronic Tagging
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We present the measurement of the first to fourth order moments of the four-momentum transfer squared, $q^2$, of inclusive $B rightarrow X_c ell^+ u_{ell}$ decays using the full Belle data set of 711 $mathrm{fb}^{-1}$ of integrated luminosity at the $Upsilon(4S)$ resonance where $ell = e, mu$. The determination of these moments and their systematic uncertainties open new pathways to determine the absolute value of the CKM matrix element $V_{cb}$ using a reduced set of matrix elements of the heavy quark expansion. In order to identify and reconstruct the $X_c$ system, we reconstruct one of the two $B$-mesons using machine learning techniques in fully hadronic decay modes. The moments are measured with progressively increasing threshold selections on $q^2$ starting with a lower value of 3.0 $mathrm{GeV}^2$ in steps of 0.5 $mathrm{GeV}^2$ up to a value of 10.0 $mathrm{GeV}^2$. The measured moments are further unfolded, correcting for reconstruction and selection effects as well as QED final state radiation. We report the moments separately for electron and muon final states and observe no lepton flavor universality violating effects.
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We present measurements of partial branching fractions of inclusive semileptonic $B to X_u , ell^+, u_{ell}$ decays using the full Belle data set of 711 fb$^{-1}$ of integrated luminosity at the $Upsilon(4S)$ resonance and for $ell = e, mu$. Inclusi
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We present measurements of the first six hadronic mass moments in semileptonic $B rightarrow X_c ell u $ decays. The hadronic mass moments, together with other observables of inclusive $B$ decays, can be used to determine the CKM matrix element $|{V
_{cb}}|$ and mass of the $b$-quark $m_b$ in the context of Heavy Quark Expansions of QCD. The Belle~II data recorded at the $Upsilon (4S)$ resonance in 2019 and 2020 (March-July), corresponding to an integrated luminosity of $34.6;mathrm{fb}^{-1}$, is used for this measurement. The decay $Upsilon (4S) rightarrow B overline{B}$ is reconstructed by applying the hadronic tagging algorithm provided by the Full Event Interpretation to fully reconstruct one $B$ meson. The second $B$ meson is reconstructed inclusively by selecting a high-momentum lepton. The $X_c$ system is identified by the remaining reconstructed tracks and clusters in the electromagnetic calorimeter. We report preliminary results for the hadronic mass moments $langle M_X^n rangle $ with $n=1,dots,6$, measured as a function of a lower cut on the lepton momentum in the signal $B$ rest frame.
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The first measurements of differential branching fractions of inclusive semileptonic ${B to X_u , ell^+, u_{ell}}$ decays are performed using the full Belle data set of 711 fb$^{-1}$ of integrated luminosity at the $Upsilon(4S)$ resonance and for $e
ll = e, mu$. Differential branching fractions are reported as a function of the lepton momentum, the four-momentum-transfer squared, light-cone momenta, the hadronic mass, and the hadronic mass squared. They are obtained by subtracting the backgrounds from semileptonic ${B to X_c , ell^+, u_{ell}}$ decays and other processes, and corrected for resolution and acceptance effects. The measured distributions are compared to predictions from inclusive and hybrid ${B to X_u , ell^+, u_{ell}}$ calculations.
The branching fractions of the decays $B^{+} to eta ell^{+} u_{ell}$ and $B^{+} to eta^{prime} ell^{+} u_{ell}$ are measured, where $ell$ is either an electron or a muon, using a data sample of $711,{rm fb}^{-1}$ containing $772 times 10^6 Bbar{B}$
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