K. Tanida

Test of lepton flavor universality with $B ˉ \to D^{()} τ^{-} ν ˉ_{τ}$ and $B ˉ \to D^{()} ℓ^{-} ν ˉ_{ℓ}$ decays at Belle II

Belle II Collaboration, M. Abumusabh, I. Adachi +494

We test lepton flavor universality with a measurement of the branching-fraction ratios $R(D^{(*)}) \equiv \mathcal{B}(\bar{B} \rightarrow D^{(*)} τ^{-} \barν_τ)/\mathcal{B}(\bar{B}…

Search for the lepton-flavor-violating decay $τ^{\pm} \to μ^{\pm} γ$ at Belle II

Belle II Collaboration, M. Abumusabh, I. Adachi +466

We present a search for the lepton-flavor-violating decay $τ^{\pm} \to μ^{\pm} γ$ using a data sample that corresponds to an integrated luminosity of 428 fb $^{- 1}$ recorded by the Bel…

First measurement of the masses of the $Υ_{1} (1 D)$ and $Υ_{3} (1 D)$ states and the energy dependence of the cross sections for $e^{+} e^{-} \to Υ_{J} (1 D) η$ and $e^{+} e^{-} \to Υ_{J} (1 D) π^{+} π^{-}$

Belle, Belle II Collaborations, : +398

We study the processes $e^{+} e^{-} \to Υ_{J} (1 D) η$ and $e^{+} e^{-} \to Υ_{J} (1 D) π^{+} π^{-}$ at center-of-mass energies $s$ =(10.73 -- 11.02) GeV using a $142.5 fb^{- 1}$ data sample, in…

Observation of the decays $B^{+} \to Σ_{c} (2455)^{++} Ξ ˉ_{c}^{' -}$ and $B^{0} \to Σ_{c} (2455)^{0} Ξ ˉ_{c}^{'0}$

Belle, Belle II Collaborations, : +403

We report the first observation of the decays $B^{+} \to Σ_{c} (2455)^{++} Ξ ˉ_{c}^{' -}$ and $B^{0} \to Σ_{c} (2455)^{0} Ξ ˉ_{c}^{'0}$ , with significances of $6.4 σ$ a…

Study of $e^{+} e^{-} \to h^{+} h^{-} J / ψ (h = π, K, p)$ via initial-state radiation at Belle~II

Belle II Collaboration, M. Abumusabh, I. Adachi +417

Using a data sample of 427.9 fb $^{- 1}$ collected by the Belle~II detector at or near the $Υ (4 S)$ and $Υ (10753)$ resonances, the cross sections for $e^{+} e^{-} \to h^{+} h^{-} J / ψ$ $(h = π / K / p)$ …

Measurement of inclusive $B \to X_{u} ℓ ν$ partial branching fractions and $∣ V_{u b} ∣$ at Belle II

Belle II Collaboration, M. Abumusabh, I. Adachi +419

A sample of 365 fb $^{- 1}$ of $e^{+} e^{-} \to Υ (4 S) \to B B ˉ$ data collected by the Belle II experiment is used to measure the partial branching fractions of charmless semileptonic…

Measurements of the mass difference $m (B^{0}) - m (B^{+})$ and the energy dependence of the cross-section ratio $σ (e^{+} e^{-} \to B^{0} B ˉ^{0}) / σ (e^{+} e^{-} \to B^{+} B^{-})$ at Belle and Belle II

Belle, Belle II Collaborations, : +396

Using data samples collected by the Belle and Belle II experiments at the $Υ (4 S)$ resonance with integrated luminosities of 571 fb $^{- 1}$ and 365 fb $^{- 1}$ , respectively, we measur…

First search for $B \to X_{s} ν ν ˉ$ decays

Belle II Collaboration, M. Abumusabh, I. Adachi +440

We report the first search for the flavor-changing neutral-current decays $B \to X_{s} ν ν ˉ$ , where $X_{s}$ is a hadronic system with strangeness equal to 1, in data coll…

hep-ex2025★ 2 cited

First measurements of the branching fractions for the decay modes $Ξ_{c}^{0} \to Λ η$ and $Ξ_{c}^{0} \to Λ η^{'}$ and search for the decay $Ξ_{c}^{0} \to Λ π^{0}$ using Belle and Belle II data

Belle, Belle II Collaborations, : +321

Using data samples of 988.4 fb $^{- 1}$ and 427.9 fb $^{- 1}$ collected with the Belle and Belle II detectors, we present a study of the singly Cabibbo-suppressed decays $Ξ_c^{0} \to Λ…

Search for $C P$ violation in $Ξ_{c}^{+} \to Σ^{+} h^{+} h^{-}$ and $Λ_{c}^{+} \to p h^{+} h^{-}$ at Belle II

Belle II Collaboration, M. Abumusabh, I. Adachi +344

We report decay-rate $C P$ asymmetries of the singly-Cabibbo-suppressed decays $Ξ_{c}^{+} \to Σ^{+} h^{+} h^{-}$ and $Λ_{c}^{+} \to p h^{+} h^{-}$ , with $h = K, π$ , measured using 428 fb $^{- 1}$ of $e^{+} e^{-}$ col…

nucl-ex2025★ 3 cited

Measurement of $^{3, 4}$ He( $K^{-}, π^{0}$ ) $_{Λ}^{3, 4}$ H reaction cross section and evaluation of hypertriton $Λ$ binding energy

T. Akaishi, H. Asano, X. Chen +32

Light $s$ -shell hypernuclei ( $_{Λ}^{3, 4} H$ ) and their ground-state properties are crucial benchmarks in hypernuclear physics. In particular, comparing the production cross sec…

Observation of $e^{+} e^{-} \to η Υ (2 S)$ and search for $e^{+} e^{-} \to η Υ (1 S), γ X_{b}$ at $s$ near 10.75 GeV

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

We present an analysis of the processes $e^{+} e^{-} \to η Υ (1 S)$ , $η Υ (2 S)$ , and $γ X_{b}$ with $X_{b} \to π^{+} π^{-} χ_{b J}, χ_{b J} \to γ Υ (1 S)$ $(J = 1, 2)$ reconstructed from $γγπ^+π^-\ell^+\ell^-~(…

Search for $e^{+} e^{-} \to γ χ_{b J}$ ( $J$ = 0, 1, 2) near $s = 10.746$ GeV at Belle II

Belle II Collaboration, M. Abumusabh, I. Adachi +399

We search for the $e^{+} e^{-} \to γ χ_{b J}$ ( $J$ = 0, 1, 2) processes at center-of-mass energies $s$ = 10.653, 10.701, 10.746, and 10.804 GeV. These data were collected with the…

Cross sections of $η$ mesons in $p$ $+$ $p$ collisions at forward rapidity at $s = 500$ GeV and central rapidity at $s = 510$ GeV

PHENIX Collaboration, N. J. Abdulameer, U. Acharya +497

We present the first measurements of the forward and midrapidity $η$ -meson cross sections from $p$ $+$ $p$ collisions at $s = 500$ and $510$ ~GeV, respectively. We also report th…

nucl-ex2025

Low-mass vector-meson production at forward rapidity in $p$ $+$ $p$ and Au $+$ Au collisions at $s_{_{N N}} = 200$ ~GeV

PHENIX Collaboration, N. J. Abdulameer, U. Acharya +352

The PHENIX experiment at the Relativistic Heavy Ion Collider has measured low-mass vector-meson ( $ω + ρ$ and $ϕ$ ) production through the dimuon decay channel at forward rapidity $(1.…

Search for the lepton-flavor-violating $τ^{-} \to e^{\mp} ℓ^{\pm} ℓ^{\mp}$ 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 $τ^{-} \to e^{\mp} ℓ^{\pm} ℓ^{-}$ , where $ℓ$ is a muon or an electron, using a data sample…

hep-ex2025★ 3 cited

Observation of the decays $B^{+} \to Σ_{c} (2455)^{++} Ξ_{c}^{-}$ and $B^{0} \to Σ_{c} (2455)^{0} Ξ_{c}^{0}$

Belle, Belle II Collaborations, : +386

We report the first observation of the two-body baryonic decays $B^{+} \to Σ_{c} (2455)^{++} Ξ_{c}^{-}$ and $B^{0} \to Σ_{c} (2455)^{0} Ξ_{c}^{0}$ with significance…

Measurement of the $D^{0} \to K^{-} π^{+} e^{+} e^{-}$ branching fraction and search for $D^{0} \to π^{+} π^{-} e^{+} e^{-}$ and $D^{0} \to K^{+} K^{-} e^{+} e^{-}$ decays at Belle

Belle, Belle II Collaborations, : +481

We present a study of the rare charm meson decays $D^{0} \to K^{+} K^{-} e^{+} e^{-}$ , $π^{+} π^{-} e^{+} e^{-}$ , and $K^{-} π^{+} e^{+} e^{-}$ using a 942 fb $^{- 1}$ data set c…

Search for an Axion-Like Particle in $B \to K^{(*)} a (\to γ γ)$ Decays at Belle

Belle, Belle II Collaborations, : +422

We report a search for an axion-like particle $a$ in $B \to K^{(*)} a (\to γ γ)$ decays using data collected with the Belle detector at the KEKB asymmetric energy elec…

hep-ex2025★ 2 cited

Measurement of the CP asymmetry in $D^{+} \to π^{+} π^{0}$ decays at Belle II

Belle II Collaboration, I. Adachi, L. Aggarwal +402

We measure the CP asymmetry in $D^{+} \to π^{+} π^{0}$ decays reconstructed in $e^{+} e^{-}$ collisions at the Belle II experiment using a data set corresponding to an integrated luminosity…

Charged-hadron identification at Belle II

Belle II Collaboration, I. Adachi, H. Ahmed +408

The Belle II experiment's ability to identify particles critically affects the sensitivity of its measurements. We describe Belle II's algorithms for identifying charged particles…

nucl-ex2025

Measurement of $Λ$ Polarization in the $π^{-} p \to K^{0} Λ$ Reaction at $p_{π^{-}} = 1.33$ GeV/ $c$ toward a New $Λ p$ Scattering Experiment

PARC E40 Collaboration, T. Sakao, K. Miwa +69

This paper presents high-precision experimental data of the polarization of the $Λ$ hyperon in the $π^{-} p \to K^{0} Λ$ reaction, measured in the angular range $0.6<\cos θ^{CM}_{K0…

hep-ex2025★ 4 cited

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…