Related papers: First Physics Results From Belle
With 6.2 fb^-1 of data collected on the Upsilon(4S), Belle reports its first measurement of sin 2\phi_1 = 0.45^{+0.43}_{-0.44}(stat)^{+0.07}_{-0.09}(sys). The result was obtained by fitting the proper time distribution of flavor tagged and…
We report the first observation of $B^{\pm} \to \chi_{c1} \pi^{\pm}$, the Cabibbo- and color-suppressed decay in a data sample of $386\times 10^6$~$B\bar B$ events collected at the $\Upsilon(4S)$ resonance with the Belle detector at the…
The precise measurement of the CKM angle $\phi_3$ is important to further test the Standard Model description of $CP$ violation. The small values of the branching fractions of the decays involved in the measurement limits the precision,…
We report improved measurements of time-dependent CP violation parameters for $B^0(\bar{B}^0) \to J/\psi \pi^0$ decay. This analysis is based on 535 million $B\bar{B}$ pairs accumulated at the $\Upsilon(4S)$ resonance with the Belle…
We report on the first Belle II measurements of branching fractions and CP-violating charge asymmetries in charmless $B$ decays. We use 34.6 fb$^{-1}$ from electron-positron collisions collected in 2019 and 2020 at the $\Upsilon(4S)$…
We report the first observation of CP-violating asymmetries in B0 --> pi+pi- decays based on a 140 fb-1 data sample collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider. We reconstruct…
We determine the branching fractions ${\mathcal{B}}$ and $CP$ asymmetries ${\mathcal{A}_{{\it CP}}}$ of the decays $B^+ \rightarrow \pi^+ \pi^0$ and $B^+ \rightarrow K^+ \pi^0$. The results are based on a data set containing 198 million…
The Belle II collaboration operates a substantially upgraded Belle detector at the SuperKEKB energy-asymmetric e+ e- collider. Belle II will start recording collisions at the Upsilon(4S) energy in 2018, aiming to collect by 2025 50 ab^{-1}…
We present measurements of time-dependent CP asymmetries in $B^0 \to \omega K_S^0$, $f_0 (980) K_S^0$, $K_S^0 \pi^0$ and $K^+ K^- K_S^0$ based on a sample of 535 $\times 10^6$ $B\bar{B}$ pairs collected at the $\Upsilon(4S)$ resonance with…
We report an improved measurement of the decay $B^0 \to \pi^0 \pi^0$, using a data sample of 535 $\times 10^6 B\bar{B}$ pairs collected at the $\Upsilon(4S)$ resonance with the Belle detector at the KEKB asymmetric energy $e^+ e^-$…
We study B- meson decays to pbar Lambda D(*)0 final states using a sample of 657 * 10^6 B Bbar events collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+ e- collider. The observed branching…
The Belle II experiment operates at the SuperKEKB asymmetric-energy $e^+e^-$ collider. During the Run 1 data taking, we have collected an integrated luminosity of $424\text{ fb}^{-1}$ of collision data at the energy near the $\Upsilon (4S)$…
We report measurements of radiative B decays with K eta gamma final states, using a data sample of 140 /fb recorded at the Upsilon(4S) resonance with the Belle detector at the KEKB e+e- asymmetric energy collider. We observe B -> K eta…
We present a measurement of time-dependent rate asymmetries in $B^0\to \phi K^0_S$ decays to search for non-standard-model physics in $b\to q \overline{q}s$ transitions. The data sample is collected with the Belle II detector at the…
We report the recent measurements of $B^0\to J/\psi\pi^0$ and other CP violation modes based on the data collected by the Belle experiment at the KEKB collider. The CP asymmetry parameters for the decay $B^0\to J/\psi\pi^0$ have previously…
We present a measurement of the branching fraction and time-dependent CP violation parameters in B0 --> a_1^+-(1260) pi^-+ decays. The results are obtained from the final data sample containing 772x10^6 BBbar pairs collected at the…
We report a measurement of the $C\!P$-violating parameters $A$ and $S$ in $B^{0}\to K_{S}^{0} \pi^{0}$ decays at Belle II using a sample of $387\times 10^{6}$ $B\bar{B}$ events recorded in $e^{+}e^{-}$ collisions at a center-of-mass energy…
We measure the ratio of branching fractions for the $\Upsilon (4S)$ decays to $B^+B^-$ and $B^0\bar{B}{}^0$ using $B^+ \rightarrow J/\psi(\ell\ell) K^+$ and $B^0 \rightarrow J/\psi(\ell\ell) K^0$ samples, where $J/\psi(\ell\ell)$ stands for…
We report the first observation of radiative decay B^0 -> \phi K^0 \gamma using a data sample of 772x10^6 BBar pairs collected at the Y(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider. We observe a signal…
We report branching fractions and charge asymmetries for exclusive decays of charged and neutral B mesons to two-body final states containing a charmonium meson, J/psi or psi(2S). This result is based on a 29.4 fb^{-1} data sample collected…