D. Kumar

activity

20232026

most citedTest of lepton flavor universality with measurements of

R (D^{+})

and

R (D^{*+})

using semileptonic

B

tagging at the Belle II experiment

5 citations · 32 across the 21 of their papers we have counts for

collaborators

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25 papers · 1 filter

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

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…

hep-ex2025★ 1 cited

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…

hep-ex2025

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…

hep-ex2025

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^-~(…

hep-ex2025

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…

hep-ex2025★ 1 cited

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★ 1 cited

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…

hep-ex2025★ 1 cited

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★ 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…

hep-ex2025

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

Belle, Belle II Collaborations, : +375

We present the results of a search for the charged-lepton-flavor violating decays $B^{0} \to K^{* 0} τ^{\pm} ℓ^{\mp}$ , where $ℓ^{\mp}$ is either an electron or a muon. The…

hep-ex2025★ 1 cited

Search for lepton-flavor-violating $τ^{-} \to ℓ^{-} K_{s}^{0}$ decays at Belle and Belle II

Belle, Belle II Collaborations, : +419

We present the results of a search for charged-lepton-flavor violating decays $τ^{-} \to ℓ^{-} K_{S}^{0}$ , where $ℓ^{-}$ is either an electron or a muon. We combine $e…

hep-ex2025★ 3 cited

Search for $B^{0} \to K^{* 0} τ^{+} τ^{-}$ decays at the Belle II experiment

Belle II Collaboration, I. Adachi, K. Adamczyk +446

We present a search for the rare flavor-changing neutral-current decay $B^{0} \to K^{* 0} τ^{+} τ^{-}$ with data collected by the Belle II experiment at the SuperKEKB electron-positro…

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-ex2025

Measurement of the Branching Fraction of $Λ_{c}^{+} \to p K_{S}^{0} π^{0}$ at Belle

The Belle, Belle II Collaborations, : +426

We report a precise measurement of the ratio of branching fractions $B (Λ_{c}^{+} \to p K_{S}^{0} π^{0}) / B (Λ_{c}^{+} \to p K^{-} π^{+})$ using 980 fb $^{- 1}$ of $e^{+} e^{-}$ data from th…

hep-ex2025★ 4 cited

Measurement of $B^{+} \to τ^{+} ν_{τ}$ branching fraction with a hadronic tagging method at Belle II

Belle II Collaboration, I. Adachi, K. Adamczyk +341

We present a measurement of the branching fraction of $B^{+} \to τ^{+} ν_{τ}$ decays using $(387 \pm 6) \times 1 0^{6}$ $Υ (4 S)$ collected between 2019 and 2022 with the Belle II detector at the S…

hep-ex2025

Search for Pcs(4459) and Pcs(4338) in Upsilon(1S,2S) inclusive decays at Belle

I. Adachi, L. Aggarwal, H. Ahmed +402

Using data samples of 102 million Upsilon(1S) events and 158 million Upsilon(2S) events collected by the Belle detector at the KEKB asymmetric-energy $e^{+} e^{-}$ collider, we search f…

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 the inclusive branching fractions for $B_{s}^{0}$ decays into $D$ mesons via hadronic tagging

Belle, Belle II Collaborations, : +452

We report measurements of the absolute branching fractions $B (B_{s}^{0} \to D_{s}^{\pm} X)$ , $B (B_{s}^{0} \to D^{0} / D ˉ^{0} X)$ , and $B (B_{s}^{0} \to D^{\pm} X)$ , w…

hep-ex2024★ 4 cited

Production cross sections of light and charmed mesons in $e^{+} e^{-}$ annihilation near 10.58 GeV

Belle Collaboration, R. Seidl, I. Adachi +131

We report measurements of production cross sections for $ρ^{+}$ , $ρ^{0}$ , $ω$ , $K^{*+}$ , $K^{* 0}$ , $ϕ$ , $η$ , $K_{S}^{0}$ , $f_{0} (980)$ , $D^{+}$ , $D^{0}$ , $D_{s}^{+}$ , $D^{*+}$ , $D^{* 0}$ , and $D^{*+}…

hep-ex2024★ 1 cited

Measurement of $B \to K^{*} (892) γ$ decays at Belle II

Belle II Collaboration, I. Adachi, L. Aggarwal +451

We present measurements of $B \to K^{*} (892) γ$ decays using $365 fb^{- 1}$ of data collected from 2019 to 2022 by the Belle~II experiment at the SuperKEKB asymmetric-energy…

hep-ex2024★ 2 cited

Observation of time-dependent $C P$ violation and measurement of the branching fraction of $B^{0} \to J / ψ π^{0}$ decays

Belle II Collaboration, I. Adachi, L. Aggarwal +391

We present a measurement of the branching fraction and time-dependent charge-parity ( $C P$ ) decay-rate asymmetries in $B^{0} \to J / ψ π^{0}$ decays. The data sample was collected with the…

hep-ex2024★ 4 cited

Search for a heavy neutral lepton that mixes predominantly with the tau neutrino

Belle Collaboration, M. Nayak, S. Dey +165

We report a search for a heavy neutral lepton (HNL) that mixes predominantly with $ν_{τ}$ . The search utilizes data collected with the Belle detector at the KEKB asymmetric energy $e…

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

First measurement of the masses of the Υ1​(1D) and Υ3​(1D) states and the energy dependence of the cross sections for e+e−→ΥJ​(1D)η and e+e−→ΥJ​(1D)π+π−

Measurement of inclusive B→Xu​ℓν partial branching fractions and ∣Vub​∣ at Belle II

Measurements of the mass difference m(B0)−m(B+) and the energy dependence of the cross-section ratio σ(e+e−→B0Bˉ0)/σ(e+e−→B+B−) at Belle and Belle II

Observation of e+e−→ηΥ(2S) and search for e+e−→ηΥ(1S), γXb​ at s​ near 10.75 GeV

Search for e+e−→γχbJ​ (J = 0, 1, 2) near s​=10.746 GeV at Belle II

Search for the lepton-flavor-violating τ−→e∓ℓ±ℓ∓ decays at Belle II

Measurement of the D0→K−π+e+e− branching fraction and search for D0→π+π−e+e− and D0→K+K−e+e− decays at Belle

Search for an Axion-Like Particle in B→K(∗)a(→γγ) Decays at Belle

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

Search for lepton flavor-violating decay modes B0→K∗0τ±ℓ∓ (ℓ=e,μ) with hadronic B-tagging at Belle and Belle II

Search for lepton-flavor-violating τ−→ℓ−Ks0​ decays at Belle and Belle II

Search for B0→K∗0τ+τ− decays at the Belle II experiment

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

Measurement of the Branching Fraction of Λc+​→pKS0​π0 at Belle

Measurement of B+→τ+ντ​ branching fraction with a hadronic tagging method at Belle II

Search for Pcs(4459) and Pcs(4338) in Upsilon(1S,2S) inclusive decays at Belle

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 the inclusive branching fractions for Bs0​ decays into D mesons via hadronic tagging

Production cross sections of light and charmed mesons in e+e− annihilation near 10.58 GeV

Measurement of B→K∗(892)γ decays at Belle II

Observation of time-dependent CP violation and measurement of the branching fraction of B0→J/ψπ0 decays

Search for a heavy neutral lepton that mixes predominantly with the tau neutrino

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

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 $e^{+} e^{-} \to Υ_{J} (1 D) π^{+} π^{-}$

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

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

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

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

Search for the lepton-flavor-violating $τ^{-} \to e^{\mp} ℓ^{\pm} ℓ^{\mp}$ decays at Belle II

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

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

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

Search for lepton-flavor-violating $τ^{-} \to ℓ^{-} K_{s}^{0}$ decays at Belle and Belle II

Search for $B^{0} \to K^{* 0} τ^{+} τ^{-}$ decays at the Belle II experiment

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

Measurement of the Branching Fraction of $Λ_{c}^{+} \to p K_{S}^{0} π^{0}$ at Belle

Measurement of $B^{+} \to τ^{+} ν_{τ}$ branching fraction with a hadronic tagging method at Belle II

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 the inclusive branching fractions for $B_{s}^{0}$ decays into $D$ mesons via hadronic tagging

Production cross sections of light and charmed mesons in $e^{+} e^{-}$ annihilation near 10.58 GeV

Measurement of $B \to K^{*} (892) γ$ decays at Belle II

Observation of time-dependent $C P$ violation and measurement of the branching fraction of $B^{0} \to J / ψ π^{0}$ decays