Related papers: Belle II Experiment Network and Computing
This contribution illustrates a new search for the flavor-changing neutral-current decay ${B^+ \to K^+ \nu \bar \nu}$ performed by the Belle II experiment at the SuperKEKB asymmetric-energy electron-positron collider. In this study, a…
The Belle II detector is currently under construction at the SuperKEKB electron-positron high-luminosity collider, that will provide an instantaneous luminosity 40 times higher than that of KEKB. There- fore the Belle-II VerteX Detector…
With a design luminosity of 50 ab$^{-1}$ and detectors with tracking capabilities extending beyond 1 m, the Belle II experiment is the perfect laboratory for the search of particles that couple weakly to the Standard Model and have a…
In 2024, the Belle II experiment resumed data taking after the Long Shutdown 1, which was required to install a two-layer pixel detector and upgrade accelerator components. We describe the challenges of this shutdown and the operational…
The Time-Of-Propagation (TOP) counter is a ring-imaging Cherenkov detector designed to identify the charged hadrons in the barrel region of the Belle II detector. The Belle II experiment collected data delivered by the SuperKEKB accelerator…
We present preliminary results on the reconstruction of the $B^0\to J\mskip 1mu / \psi\mskip 2mu K^0_{\scriptscriptstyle L}$ decay, where $J\mskip 1mu / \psi\mskip 2mu\to\mu^+\mu^-$ or $e^+e^-$. Using a dataset corresponding to a luminosity…
SuperKEKB is the e-/e+ collider which targets the world highest luminosity. In recent operation, SuperKEKB achieved a new world record of $4.71\times 10^{34} cm^{-2}s^{-1}$ for luminosity with the beam current of 1.4 A. In the future, the…
For the Belle II experiment at KEK (Tsukuba, Japan) the KEKB accelerator was upgraded to deliver a 40 times larger instantaneous luminosity than before, which requires an increased radiation hardness of the detector components. As the…
We report the recent results of a search for the decay B- --> tau- anti-nu_tau, observations of new resonances X, Y and Z, and the first results from Upsilon(5S) data collected with the Belle detector at KEKB e+e- collider.
A search for the flavor-changing neutral-current decay $B^{+}\to K^{+}\nu\bar{\nu}$ is performed at the Belle II experiment at the SuperKEKB asymmetric energy electron-positron collider. The results are based on a data sample corresponding…
We report a search for lepton-flavor-violating decays $\tau^- \to \ell^- \phi$ ($\ell^- =e^-,\mu^-$) at the Belle II experiment, using a sample of electron-positron data produced at the SuperKEKB collider in 2019-2021 and corresponding to…
The Belle II detector at the SuperKEKB accelerator observed the first collisions in April this year. Until mid-summer, the first commissioning run uses a reduced version of the full vertex detector. Nevertheless, this phase is an excellent…
Results on two inclusive Vub measurements at Belle are presented. We also present a new measurement of the branching fraction for Ds->phi pi. A data sample of 78.1fb^-1 accumulated using the Belle detector at the KEKB asymmetric e^+e^-…
Decays of $B$ mesons involving the transition of a $b$ quark into an $s$ quark are good probes of physics beyond the standard model. Such decays are studied at the Belle II experiment, a detector located along the SuperKEKB…
We report the recent results related to $\pi-K$ interactions based on the data collected by the Belle experiment at the KEKB collider. This includes the branching fraction and $CP$ asymmetry measurements of $B^+\to K^+K^-\pi^+$ decay,…
The Belle-II VerteX Detector (VXD) is a 6 layers silicon tracker device that will cope with an unprecedented luminosity of 8 x 10^35 cm-2 s-1 achievable by the new SuperKEKB e+e- collider, now under commissioning at the KEK laboratory…
The BELLE detector has already accumulated e^+ e^- collision data at the KEKB-collider corresponding to 600 fb^-1. BaBar has accumulated data of approximately 390 fb^-1 at PEP-II. Both are running on asymmetric energy e^+ e^- colliders at…
The CKM angle $\phi_3$ is less precisely known than the angle $\phi_1$ and the only one that is accessible with tree-level decays in a theoretically clean way. The key method to measure $\phi_3$ is through the interference between $B^+\to…
Results on a number of rare hadronic B decays are presented. A data sample of $29.1 {\rm fb}^{-1}$ accumulated using the Belle detector at the KEKB asymmetric $e^+e^-$ collider operating at the $\Upsilon(4S)$ resonance is used.
The Belle II detector operating at the future upgrade to the KEKB accelerator will perform high-statistics precision investigations into the flavor sector of the Standard Model. As charged hadron identification is a vital element of the…