K. Nakamura

activity

20102026

most citedMeasurement of long-range angular correlation and quadrupole anisotropy of pions and (anti)protons in central

d

+

Au collisions at

s_{_{N N}}

=200 GeV

175 citations · 948 across the 67 of their papers we have counts for

collaborators

74 papers

hep-ex2026

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}…

hep-ex2026

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…

hep-ex2026

Search for the $B^{0} \to K_{S}^{0} τ^{+} τ^{-}$ decay

Belle, Belle II Collaborations, : +432

We present the first search for $B^{0} \to K_{S}^{0} τ^{+} τ^{-}$ decays. We look for signal decays in $B^{0} B ˉ^{0}$ events produced in asymmetric-energy electron-positron collisions. T…

hep-ex2026

Search for axion-like particles decaying to two photons at Belle II

Belle II Collaboration, M. Abumusabh, I. Adachi +450

Axion-like particles (ALPs) are predicted in many extensions of the Standard Model and provide a well-motivated portal between visible and hidden sectors through their coupling to…

physics.ins-det2026

Development for the Belle II vertex detector upgrade with depleted monolithic active pixel sensors

Y. Onuki, M. Babeluk, T. Bergauer +85

The vertex detector upgrade project for the Belle II experiment, based on CMOS depleted monolithic active pixel sensor technology, is planned to be carried out in conjunction with…

hep-ex2026

Charged-lepton identification at Belle~II

Belle II Collaboration, M. Abumusabh, I. Adachi +409

Effective particle identification capabilities are a strategic priority for the physics program of the Belle~II experiment. We describe the algorithms used at Belle~II for identify…

hep-ex2026

First evidence of $X (3872) \to π^{0} χ_{c 0} (1 P)$ and search for $X (3915) \to π^{0} χ_{c 1} (1 P)$

Belle, Belle II Collaborations, : +412

We search for the pionic transitions $X (3872) \to π^{0} χ_{c J} (1 P)$ $(J = 0, 1, 2)$ and $X (3915) \to π^{0} χ_{c 1}$ in $B^{+} \to π^{0} χ_{c J} K^{+}$ decays using the Belle and Belle~II data samples c…

hep-ex2026

Measurement of mixing-induced CP violation in the decay $B^{0} \to π^{0} π^{0}$

Belle II Collaboration, M. Abumusabh, I. Adachi +437

Measurements of charge-parity (CP) violation in quark transitions provide stringent tests of the current theory and sensitive probes of particles or interactions beyond it. We repo…

physics.ins-det2026

Application of exhaustive simulation flow for advanced performance prediction of monolithic active pixel sensors

E. Sacchetti, M. Babeluk, T. Bergauer +86

Monolithic active pixel sensor (MAPS) developments have pushed the detection performance in various directions, especially relative to timing where nanosecond-level precision is no…

physics.ins-det2026

Upgrade of the Belle II Vertex Detector with Depleted Monolithic CMOS Active Pixel Sensors

Belle II VTX Collaboration

The Belle II experiment, operating at the asymmetric SuperKEKB $e^{+} e^{-}$ collider, is preparing an upgrade of its vertex detector to cope with an increased luminosity of $6 \times 1…

physics.ins-det2025

Radiation damage study of Belle II silicon strip sensors with 90 MeV electron irradiation

K. Adamczyk, H. Aihara, K. Amos +58

The silicon strip sensors of the Belle II silicon vertex detector were irradiated with 90 MeV electron beams up to an equivalent 1-MeV-neutron fluence of $3.0\times 10^{13}~{\rm n}…

physics.ins-det2025

Operational experience and performance of the Silicon Vertex Detector after the first long shutdown of Belle II

K. Ravindran, K. Adamczyk, H. Aihara +62

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 desc…

hep-ex2025★ 5 cited

Test of lepton flavor universality with measurements of $R (D^{+})$ and $R (D^{*+})$ using semileptonic $B$ 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 \to…

hep-ex2024

Search for lepton flavor-violating decay modes $B^{0} \to K_{S}^{0} τ^{\pm} ℓ^{\mp} (ℓ = μ, e)$ with hadronic $B$ -tagging at Belle and Belle II

Belle, Belle II Collaborations, : +425

We present the first search for the lepton flavor-violating decay modes $B^{0} \to K_{S}^{0} τ^{\pm} ℓ^{\mp} (ℓ = μ, e)$ using the 711 fb $^{- 1}$ and 365 fb $^{- 1}$ data samples re…

hep-ex2024

Measurement of branching fractions, CP asymmetry, and isospin asymmetry for $B \to ργ$ decays using Belle and Belle II data

Belle II Collaboration, I. Adachi, K. Adamczyk +407

We present measurements of $B^{+} \to ρ^{+} γ$ and $B^{0} \to ρ^{0} γ$ decays using a combined data sample of $772 \times 1 0^{6}$ $B B$ pairs collected by the Bel…

nucl-ex2024★ 7 cited

Centrality dependence of Lévy-stable two-pion Bose-Einstein correlations in $s_{_{N N}} = 200$ GeV Au $+$ Au collisions

PHENIX Collaboration, N. J. Abdulameer, U. Acharya +394

The PHENIX experiment measured the centrality dependence of two-pion Bose-Einstein correlation functions in $s_{_{N N}} = 200$ ~GeV Au $+$ Au collisions at the Relativistic Heavy…

hep-ex2024★ 2 cited

Test of light-lepton universality in $τ$ decays with the Belle II experiment

Belle II Collaboration, I. Adachi, K. Adamczyk +428

We present a measurement of the ratio $R_{μ} = B (τ^{-} \to μ^{-} ν ˉ_{μ} ν_{τ}) / B (τ^{-} \to e^{-} ν ˉ_{e} ν_{τ})$ of branching fractions $B$ of the $τ$ lepton decaying t…

hep-ex2024★ 8 cited

Search for lepton-flavor-violating $τ^{-} \to μ^{-} μ^{+} μ^{-}$ decays at Belle II

Belle II Collaboration, I. Adachi, L. Aggarwal +429

We present the result of a search for the charged-lepton-flavor violating decay $τ^{-} \to μ^{-} μ^{+} μ^{-}$ using a $424 f b^{- 1}$ sample of data recorded by the Belle II experiment at the S…

hep-ex2024

Determination of the CKM angle $ϕ_{3}$ from a combination of Belle and Belle II results

Belle, Belle II Collaborations, : +399

We report a determination of the CKM angle $ϕ_{3}$ , also known as $γ$ , from a combination of measurements using samples of up to 711~fb $^{- 1}$ from the Belle experiment and up to 3…

hep-ex2024★ 7 cited

Search for Rare $b \to d ℓ^{+} ℓ^{-}$ Transitions at Belle

Belle, Belle II Collaborations, : +393

We present the results of a search for the $b \to d ℓ^{+} ℓ^{-}$ flavor-changing neutral-current rare decays $B^{+, 0} \to (η, ω, π^{+, 0}, ρ^{+, 0}) e^{+} e^{-}$ and $B^{+, 0} \to (η, ω…

hep-ex2024

Measurement of $C P$ asymmetries in $B^{0} \to K_{S}^{0} K_{S}^{0} K_{S}^{0}$ decays at Belle II

Belle II Collaboration, I. Adachi, L. Aggarwal +450

We report a measurement of decay-time dependent charge-parity ( $C P$ ) asymmetries in $B^{0} \to K_{S}^{0} K_{S}^{0} K_{S}^{0}$ decays. We use $387 \times 1 0^{6} B B ˉ$ pairs collected at…

hep-ex2024★ 13 cited

New graph-neural-network flavor tagger for Belle II and measurement of $sin 2 ϕ_{1}$ in $B^{0} \to J / ψ K_{S}^{0}$ decays

Belle II Collaboration, I. Adachi, L. Aggarwal +413

We present GFlaT, a new algorithm that uses a graph-neural-network to determine the flavor of neutral $B$ mesons produced in $Υ (4 S)$ decays. It improves previous algorithms by usin…

hep-ex2024★ 4 cited

Silicon Vertex Detector of the Belle II Experiment

S. Mondal, K. Adamczyk, L. Aggarwal +72

The silicon vertex detector (SVD) is installed at the heart of the Belle II experiment, taking data at the high-luminosity $B$ -Factory SuperKEKB since 2019. The detector has shown…

nucl-ex2023★ 8 cited

Identified charged-hadron production in $p$ $+$ Al, $^{3}$ He $+$ Au, and Cu $+$ Au collisions at $s_{_{N N}} = 200$ GeV and in U $+$ U collisions at $s_{_{N N}} = 193$ GeV

PHENIX Collaboration, N. J. Abdulameer, U. Acharya +477

The PHENIX experiment has performed a systematic study of identified charged-hadron ( $π^{\pm}$ , $K^{\pm}$ , $p$ , $p ˉ$ ) production at midrapidity in $p$ $+$ Al, $^{3}$ He $+$ Au, Cu $+$ Au c…

Test of lepton flavor universality with Bˉ→D(∗)τ−νˉτ​ and Bˉ→D(∗)ℓ−νˉℓ​ decays at Belle II

Search for the lepton-flavor-violating decay τ±→μ±γ at Belle II

Search for the B0→KS0​τ+τ− decay

Search for axion-like particles decaying to two photons at Belle II

Development for the Belle II vertex detector upgrade with depleted monolithic active pixel sensors

Charged-lepton identification at Belle~II

First evidence of X(3872)→π0χc0​(1P) and search for X(3915)→π0χc1​(1P)

Measurement of mixing-induced CP violation in the decay B0→π0π0

Application of exhaustive simulation flow for advanced performance prediction of monolithic active pixel sensors

Upgrade of the Belle II Vertex Detector with Depleted Monolithic CMOS Active Pixel Sensors

Radiation damage study of Belle II silicon strip sensors with 90 MeV electron irradiation

Operational experience and performance of the Silicon Vertex Detector after the first long shutdown of Belle II

Test of lepton flavor universality with measurements of R(D+) and R(D∗+) using semileptonic B tagging at the Belle II experiment

Search for lepton flavor-violating decay modes B0→KS0​τ±ℓ∓ (ℓ=μ,e) with hadronic B-tagging at Belle and Belle II

Measurement of branching fractions, CP asymmetry, and isospin asymmetry for B→ργ decays using Belle and Belle II data

Centrality dependence of Lévy-stable two-pion Bose-Einstein correlations in sNN​​​=200 GeV Au+Au collisions

Test of light-lepton universality in τ decays with the Belle II experiment

Search for lepton-flavor-violating τ−→μ−μ+μ− decays at Belle II

Determination of the CKM angle ϕ3​ from a combination of Belle and Belle II results

Search for Rare b→dℓ+ℓ− Transitions at Belle

Measurement of CP asymmetries in B0→KS0​KS0​KS0​ decays at Belle II

New graph-neural-network flavor tagger for Belle II and measurement of sin2ϕ1​ in B0→J/ψKS0​ decays

Silicon Vertex Detector of the Belle II Experiment

Identified charged-hadron production in p+Al, 3He+Au, and Cu+Au collisions at sNN​​​=200 GeV and in U+U collisions at sNN​​​=193 GeV

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

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

Search for the $B^{0} \to K_{S}^{0} τ^{+} τ^{-}$ decay

First evidence of $X (3872) \to π^{0} χ_{c 0} (1 P)$ and search for $X (3915) \to π^{0} χ_{c 1} (1 P)$

Measurement of mixing-induced CP violation in the decay $B^{0} \to π^{0} π^{0}$

Test of lepton flavor universality with measurements of $R (D^{+})$ and $R (D^{*+})$ using semileptonic $B$ tagging at the Belle II experiment

Search for lepton flavor-violating decay modes $B^{0} \to K_{S}^{0} τ^{\pm} ℓ^{\mp} (ℓ = μ, e)$ with hadronic $B$ -tagging at Belle and Belle II

Measurement of branching fractions, CP asymmetry, and isospin asymmetry for $B \to ργ$ decays using Belle and Belle II data

Centrality dependence of Lévy-stable two-pion Bose-Einstein correlations in $s_{_{N N}} = 200$ GeV Au $+$ Au collisions

Test of light-lepton universality in $τ$ decays with the Belle II experiment

Search for lepton-flavor-violating $τ^{-} \to μ^{-} μ^{+} μ^{-}$ decays at Belle II

Determination of the CKM angle $ϕ_{3}$ from a combination of Belle and Belle II results

Search for Rare $b \to d ℓ^{+} ℓ^{-}$ Transitions at Belle

Measurement of $C P$ asymmetries in $B^{0} \to K_{S}^{0} K_{S}^{0} K_{S}^{0}$ decays at Belle II

New graph-neural-network flavor tagger for Belle II and measurement of $sin 2 ϕ_{1}$ in $B^{0} \to J / ψ K_{S}^{0}$ decays

Identified charged-hadron production in $p$ $+$ Al, $^{3}$ He $+$ Au, and Cu $+$ Au collisions at $s_{_{N N}} = 200$ GeV and in U $+$ U collisions at $s_{_{N N}} = 193$ GeV