C. Niebuhr

activity

19952025

most citedThe Belle II Physics Book

570 citations · 8.2k across the 203 of their papers we have counts for

collaborators

225 papers

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-ex2024★ 4 cited

Machine Learning-Assisted Measurement of Lepton-Jet Azimuthal Angular Asymmetries in Deep-Inelastic Scattering at HERA

The H1 collaboration, V. Andreev, M. Arratia +141

In deep-inelastic positron-proton scattering, the lepton-jet azimuthal angular asymmetry is measured using data collected with the H1 detector at HERA. When the average transverse…

hep-ex2024

Measurement of the branching fraction and $CP$ -violating asymmetry of the decay $B^{0} \to π^{0} π^{0}$ using $387$ million bottom-antibottom meson pairs in Belle II data

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

We measure the branching fraction and $CP$ -violating flavor-dependent rate asymmetry of $B^{0} \to π^{0} π^{0}$ decays reconstructed using the Belle II detector in an electron-…

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★ 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

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…

hep-ex2024

Search for the baryon number and lepton number violating decays $τ^{-} \to Λ π^{-}$ and $τ^{-} \to Λ ˉ π^{-}$ at Belle II

Belle II Collaboration, I. Adachi, L. Aggarwal +371

We present a search for the baryon number $B$ and lepton number $L$ violating decays $τ^{-} \to Λ π^{-}$ and $τ^{-} \to Λ ˉ π^{-}$ produced from the $e^{+} e^{-} \to τ^{+} τ^{-}$ pro…

hep-ex2024★ 8 cited

The Belle II Detector Upgrades Framework Conceptual Design Report

H. Aihara, A. Aloisio, D. P. Auguste +207

We describe the planned near-term and potential longer-term upgrades of the Belle II detector at the SuperKEKB electron-positron collider operating at the KEK laboratory in Tsukuba…

hep-ex2024

Measurement of the energy dependence of the $e^{+} e^{-} \to B B ˉ$ , $B B ˉ^{}$ , and $B^{} B ˉ^{*}$ cross sections at Belle~II

Belle II Collaboration, I. Adachi, L. Aggarwal +466

We report measurements of the $e^{+} e^{-} \to B B ˉ$ , $B B ˉ^{*}$ , and $B^{*} B ˉ^{*}$ cross sections at four energies, 10653, 10701, 10746 and 10805 MeV, using data collected b…

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

Measurement of the 1-jettiness event shape observable in deep-inelastic electron-proton scattering at HERA

The H1 collaboration, V. Andreev, M. Arratia +146

The H1 Collaboration reports the first measurement of the 1-jettiness event shape observable $τ_{1}^{b}$ in neutral-current deep-inelastic electron-proton scattering (DIS). The observa…

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★ 6 cited

Measurement of groomed event shape observables in deep-inelastic electron-proton scattering at HERA

The H1 collaboration, V. Andreev, M. Arratia +145

The H1 Collaboration at HERA reports the first measurement of groomed event shape observables in deep inelastic electron-proton scattering (DIS) at $s = 319$ GeV, using data r…

hep-ex2024★ 5 cited

Observation and differential cross section measurement of neutral current DIS events with an empty hemisphere in the Breit frame

The H1 collaboration, V. Andreev, M. Arratia +146

The Breit frame provides a natural frame to analyze lepton-proton scattering events. In this reference frame, the parton model hard interactions between a quark and an exchanged bo…

hep-ex2024★ 10 cited

Search for a $μ^{+} μ^{-}$ resonance in four-muon final states at Belle II

Belle II Collaboration, I. Adachi, K. Adamczyk +401

We report on a search for a resonance $X$ decaying to a pair of muons in $e^{+} e^{-} \to μ^{+} μ^{-} X$ events in the 0.212-9.000 GeV/ $c^{2}$ mass range, using 178 fb $^{- 1}$ of…

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

A test of lepton flavor universality with a measurement of $R (D^{*})$ using hadronic $B$ tagging at the Belle II experiment

Belle II Collaboration, I. Adachi, K. Adamczyk +434

The ratio of branching fractions $R (D^{*}) = B (B \to D^{*} τ^{-} ν_{τ})$ /$\mathcal{B} (\overline{B} \rightarrow D^{*} \ell^{-} \overlineν_{\ell}…

hep-ex2024

Study of $Υ (10753)$ decays to $π^{+} π^{-} Υ (n S)$ final states at Belle II

Belle II Collaboration, I. Adachi, L. Aggarwal +393

We present an analysis of the process $e^{+} e^{-} \to π^{+} π^{-} Υ (n S)$ (where $n$ = 1, 2, or 3) reconstructed in $19.6$ $f b^{- 1}$ of Belle II data during a special run of the…

hep-ex2023

Search for the $e^{+} e^{-} \to η_{b} (1 S) ω$ and $e^{+} e^{-} \to χ_{b 0} (1 P) ω$ processes at $s = 10.745 GeV$

Belle II Collaboration, I. Adachi, L. Aggarwal +419

We search for the $e^{+} e^{-} \to η_{b} (1 S) ω$ and $e^{+} e^{-} \to χ_{b 0} (1 P) ω$ processes at a center-of-mass energy of 10.745 GeV, which is close to the peak of the $Υ (10753)$ state. We use data…

hep-ex2023★ 90 cited

Evidence for $B^{+} \to K^{+} ν ν ˉ$ decays

Belle II Collaboration, I. Adachi, K. Adamczyk +452

We search for the rare decay $B^{+} \to K^{+} ν ν ˉ$ in a $362 fb^{- 1}$ sample of electron-positron collisions at the $Υ (4 S)$ resonance collected with the Belle II det…

hep-ex2023★ 10 cited

Search for a $τ^{+} τ^{-}$ resonance in $e^{+} e^{-} \to μ^{+} μ^{-} τ^{+} τ^{-}$ events with the Belle II experiment

Belle II Collaboration, I. Adachi, K. Adamczyk +464

We report the first search for a non-standard-model resonance decaying into $τ$ pairs in $e^{+} e^{-} \to μ^{+} μ^{-} τ^{+} τ^{-}$ events in the 3.6-10 GeV/ $c^{2}$ mass range. We u…

hep-ex2023★ 16 cited

Search for a long-lived spin-0 mediator in $b \to s$ transitions at the Belle II experiment

Belle II Collaboration, I. Adachi, K. Adamczyk +411

Additional spin-0 particles appear in many extensions of the standard model. We search for long-lived spin-0 particles $S$ in $B$ -meson decays mediated by a $b \to s$ quark transiti…

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

Machine Learning-Assisted Measurement of Lepton-Jet Azimuthal Angular Asymmetries in Deep-Inelastic Scattering at HERA

Measurement of the branching fraction and CP-violating asymmetry of the decay B0→π0π0 using 387 million bottom-antibottom meson pairs in Belle II data

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

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

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

Search for the baryon number and lepton number violating decays τ−→Λπ− and τ−→Λˉπ− at Belle II

The Belle II Detector Upgrades Framework Conceptual Design Report

Measurement of the energy dependence of the e+e−→BBˉ, BBˉ∗, and B∗Bˉ∗ cross sections at Belle~II

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

Measurement of the 1-jettiness event shape observable in deep-inelastic electron-proton scattering at HERA

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

Measurement of groomed event shape observables in deep-inelastic electron-proton scattering at HERA

Observation and differential cross section measurement of neutral current DIS events with an empty hemisphere in the Breit frame

Search for a μ+μ− resonance in four-muon final states at Belle II

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

A test of lepton flavor universality with a measurement of R(D∗) using hadronic B tagging at the Belle II experiment

Study of Υ(10753) decays to π+π−Υ(nS) final states at Belle II

Search for the e+e−→ηb​(1S)ω and e+e−→χb0​(1P)ω processes at s​=10.745GeV

Evidence for B+→K+ννˉ decays

Search for a τ+τ− resonance in e+e−→μ+μ−τ+τ− events with the Belle II experiment

Search for a long-lived spin-0 mediator in b→s transitions at the Belle II experiment

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

Measurement of the branching fraction and $CP$ -violating asymmetry of the decay $B^{0} \to π^{0} π^{0}$ using $387$ million bottom-antibottom meson pairs in Belle II data

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

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

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

Search for the baryon number and lepton number violating decays $τ^{-} \to Λ π^{-}$ and $τ^{-} \to Λ ˉ π^{-}$ at Belle II

Measurement of the energy dependence of the $e^{+} e^{-} \to B B ˉ$ , $B B ˉ^{}$ , and $B^{} B ˉ^{*}$ cross sections at Belle~II

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

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

Search for a $μ^{+} μ^{-}$ resonance in four-muon final states 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

A test of lepton flavor universality with a measurement of $R (D^{*})$ using hadronic $B$ tagging at the Belle II experiment

Study of $Υ (10753)$ decays to $π^{+} π^{-} Υ (n S)$ final states at Belle II

Search for the $e^{+} e^{-} \to η_{b} (1 S) ω$ and $e^{+} e^{-} \to χ_{b 0} (1 P) ω$ processes at $s = 10.745 GeV$

Evidence for $B^{+} \to K^{+} ν ν ˉ$ decays

Search for a $τ^{+} τ^{-}$ resonance in $e^{+} e^{-} \to μ^{+} μ^{-} τ^{+} τ^{-}$ events with the Belle II experiment

Search for a long-lived spin-0 mediator in $b \to s$ transitions at the Belle II experiment