activity
20242026
collaborators

11 papers

hep-ex2026

Observation of the decays and

Belle, Belle II Collaborations, : +403

We report the first observation of the decays and , with significances of $6.4\,…

hep-ex2026

Search for the lepton-flavor-violating decays at Belle II

Belle II Collaboration, I. Adachi, L. Aggarwal +447

We present the result of a search for the charged-lepton-flavor violating decays , where is a muon or an electron, using a data sampl…

hep-ex2026

Test of lepton flavor universality with measurements of and using semileptonic tagging at the Belle II experiment

Belle II Collaboration, I. Adachi, K. Adamczyk +450

We report measurements of the ratios of branching fractions ${\cal R}(D^{(*)+}) = \frac{{\cal B}(\overline{B}{}^0 \to D^{(*)+} \,τ^- \, \overlineν_τ)}{{\cal B}(\overline{B}{}^0…

hep-ex2025

Search for a Dark Higgs Boson Produced in Association with Inelastic Dark Matter at the Belle II Experiment

Belle II Collaboration, I. Adachi, L. Aggarwal +437

Inelastic dark matter models that have two dark matter particles and a massive dark photon can reproduce the observed relic dark matter density without violating cosmological limit…

hep-ex2025

Observation of and search for at near 10.75 GeV

Belle II Collaboration, I. Adachi, L. Aggarwal +435

We present an analysis of the processes , , and with reconstructed from $γγπ^+π^…

hep-ex2025

Measurements of the mass difference and the energy dependence of the cross-section ratio at Belle and Belle II

Belle, Belle II Collaborations, : +396

Using data samples collected by the Belle and Belle II experiments at the resonance with integrated luminosities of 571 fb and 365 fb, respectively, we measu…