Related papers: Archiver System Management for Belle II Detector O…

The K-long and muon detector (KLM) constitutes the outer-most volume of the Belle II spectrometer at the interaction region of the SuperKEKB collider in Tsukuba, Japan. The KLM detector was partially upgraded since the Belle experiment by…

A key part of planning CO2 storage sites is to devise a monitoring strategy. The aim of this strategy is to fulfill the requirements of legislations and lower cost of the operation by avoiding operational problems. If CCS is going to be a…

The silicon vertex detector of the Belle experiment has been built to provide the vertex information of $B$ meson decays at the KEKB accelerator. Performance during the initial data taking period and a brief description of the upgrade plan…

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.

Semileptonic decays of $B$ mesons that proceed via $b\rightarrow u$ and $b\rightarrow c$ transitions, as well as rare leptonic $B$ decays, are fertile grounds for probing new physics beyond the Standard Model. The Belle II experiment…

We report on new flavor tagging algorithms developed to determine the quark-flavor content of bottom ($B$) mesons at Belle II. The algorithms provide essential inputs for measurements of quark-flavor mixing and charge-parity violation. We…

The Belle II experiment at KEK in Japan considers upgrading its vertex detector system to address the challenges posed by high background levels caused by the increased luminosity of the SuperKEKB collider. One proposal for upgrading the…

We report expected sensitivities for the measurement of the three angles of the Unitarity Triangle in B meson decays using 50 ab-1 of electron-positron collisions recorded by the Belle II detector at the SuperKEKB collider at KEK, Japan.

The offline processing of the data collected by the Belle detector has been recently upgraded to cope with the excellent performance of the KEKB accelerator. The 127/fb of data (120 TB on tape) collected between autumn 2003 and summer 2004…

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…

This note describes the rediscovery of $B\to\eta' K$ decays in Belle II data, both in the charged and neutral final state: $B_0\to\eta' K_S$ and $B^\pm\to\eta' K^\pm$. The $\eta'$ is searched for in two decay modes: $\eta'\to\eta\pi^+\pi^-$…

The high design luminosity of the SuperKEKB electron-positron collider is expected to result in challenging levels of beam-induced backgrounds in the interaction region. Properly simulating and mitigating these backgrounds is critical to…

We present the study of an end-to-end multi-track reconstruction algorithm for the central drift chamber of the Belle II experiment at the SuperKEKB collider using Graph Neural Networks for an unknown number of particles. The algorithm uses…

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 on the first calibration of the standard Belle II $B$-flavor tagger using the full data set collected at the $\Upsilon(4{\rm S})$ resonance in 2019 with the Belle II detector at the SuperKEKB collider, corresponding to 8.7…

The Belle and Belle II experiments have collected an 1.6 ab$^{-1}$ sample of $e^+e^-$ collision data at center-of-mass energies near the $\Upsilon(nS)$ resonances. In particular, the Belle II experiment collected a 19.2 fb$^{-1}$ sample of…

At colliders, neutral long-lived particles can be detected through displaced decay products or as missing energy. Which search strategy is better depends on the particle's decay length just as on the detector properties. We investigate the…

We report results of a search for tau lepton decays strongly suppressed in the Standard Model based on the world-largest data sample accumulated with the Belle detector at the KEKB asymmetric-energy e+e- collider. The decays include: lepton…

Many dark matter models generically predict invisible and displaced signatures at Belle II, but even striking events may be missed by the currently implemented search programme because of inefficient trigger algorithms. Of particular…

In the minimal $U(1)$ extension of the Standard Model (SM), a new gauge boson referred to as "dark photon" is predicted. The dark-photon mass can be generated from an additional Higgs mechanism associated with a dark scalar boson. At…