Z. Liptak

activity

20112026

most citedThe Belle II Physics Book

570 citations · 3.3k across the 117 of their papers we have counts for

collaborators

128 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…

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…

hep-ex2026

Two-stage Convolutional Neural Network for pseudo six-dimensional phase space reconstruction

Sayantan Mukherjee, Masao Kuriki, Zachary John Liptak +5

In particle accelerators, broad characterization of the six-dimensional (6D) beam phase space is crucial but difficult to obtain with conventional beam diagnostics. We develop a tw…

hep-ex2026

Search for the decay $B^{+} \to K^{+} τ^{+} τ^{-}$ using data from the Belle and Belle II experiments

Belle, Belle II Collaborations, : +435

We report a search for the rare decay $B^{+} \to K^{+} τ^{+} τ^{-}$ using $1.2 \times 1 0^{9}$ $Υ (4 S)$ mesons produced near threshold in electron-positron collisions and colle…

hep-ex2026

Study of $e^{+} e^{-} \to π^{+} π^{-} Υ (1 D)$ at Belle II

Belle II Collaboration, M. Abumusabh, I. Adachi +404

The bottomonium spectrum, consisting of bound states of a $b$ quark and an anti- $b$ quark, provides an excellent laboratory for probing quantum chromodynamics in the non-pertur…

hep-ex2026

A search for feebly-interacting particles in $B$ decays with missing energy at Belle

Belle, Belle II Collaborations, : +406

We present a search for an invisible hidden-sector particle $X_{inv}$ , produced in $B^{0} \to D ˉ^{0} X_{inv}$ and $B^{\pm} \to h X_{inv}$ decays, where $h = π^{\pm}$ , $…

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

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★ 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

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

Determination of $∣ V_{u b} ∣$ from simultaneous measurements of untagged $B^{0} \to π^{-} ℓ^{+} ν_{ℓ}$ and $B^{+} \to ρ^{0} ℓ^{+} ν_{ℓ}$ decays

Belle II Collaboration, I. Adachi, L. Aggarwal +417

We present a measurement of $∣ V_{u b} ∣$ from a simultaneous study of the charmless semileptonic decays $B^{0} \to π^{-} ℓ^{+} ν_{ℓ}$ and $B^{+} \to ρ^{0} ℓ^{+} ν_{ℓ}$ , where $\ell = e, μ…

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-ex2023

Search for lepton-flavor-violating $τ^{-} \to ℓ^{-} ϕ$ decays in 2019-2021 Belle II data

Belle II Collaboration, F. Abudinén, I. Adachi +575

We report a search for lepton-flavor-violating decays $τ^{-} \to ℓ^{-} ϕ$ ( $ℓ^{-} = e^{-}, μ^{-}$ ) at the Belle II experiment, using a sample of electron-positron data produced at the Su…

hep-ex2023★ 2 cited

Observation of $B \to D^{(*)} K^{-} K_{S}^{0}$ decays using the 2019-2022 Belle II data sample

Belle II Collaboration, F. Abudinén, I. Adachi +575

We present a measurement of the branching fractions of four $B^{0, -} \to D^{(*) +, 0} K^{-} K_{S}^{0}$ decay modes. The measurement is based on data from SuperKEKB electron-positron colli…

hep-ex2023★ 24 cited

Measured and projected beam backgrounds in the Belle II experiment at the SuperKEKB collider

A. Natochii, T. E. Browder, L. Cao +43

The Belle II experiment at the SuperKEKB electron-positron collider aims to collect an unprecedented data set of $50 ab^{- 1}$ to study $C P$ -violation in the $B$ -meson system…

hep-ex2023★ 3 cited

Measurement of the $B^{0} \to D^{*-} ℓ^{+} ν_{ℓ}$ branching ratio and $∣ V_{c b} ∣$ with a fully reconstructed accompanying $B$ meson in 2019-2021 Belle II data

F. Abudinén, I. Adachi, K. Adamczyk +581

We present a measurement of the $B^{0} \to D^{*-} ℓ^{+} ν_{ℓ}$ ( $ℓ = e, μ$ ) branching ratio and of the CKM parameter $∣ V_{c b} ∣$ using signal decays accompanied by a f…

hep-ex2023★ 19 cited

A test of light-lepton universality in the rates of inclusive semileptonic $B$ -meson decays at Belle II

Belle II Collaboration, L. Aggarwal, H. Ahmed +349

We present the first measurement of the ratio of branching fractions of inclusive semileptonic $B$ -meson decays, $R(X_{e/μ}) = \mathcal{B}(B\to X \, e \, ν) / \mathcal{B}(B\to X \,…

hep-ex2022★ 21 cited

Search for an invisible $Z^{'}$ in a final state with two muons and missing energy at Belle II

Belle II Collaboration, I. Adachi, K. Adamczyk +385

The $L_{μ} - L_{τ}$ extension of the standard model predicts the existence of a lepton-flavor-universality-violating $Z^{'}$ boson that couples only to the heavier lepton families.…

hep-ex2022★ 3 cited

Determination of $∣ V_{u b} ∣$ from untagged $B^{0} \to π^{-} ℓ^{+} ν_{ℓ}$ decays using 2019-2021 Belle II data

Belle II Collaboration, K. Adamczyk, L. Aggarwal +588

We present an analysis of the charmless semileptonic decay $B^{0} \to π^{-} ℓ^{+} ν_{ℓ}$ , where $ℓ = e, μ$ , from 198.0 million pairs of $B B ˉ$ mesons recorded by the Belle II…

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

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

Two-stage Convolutional Neural Network for pseudo six-dimensional phase space reconstruction

Search for the decay B+→K+τ+τ− using data from the Belle and Belle II experiments

Study of e+e−→π+π−Υ(1D) at Belle II

A search for feebly-interacting particles in B decays with missing energy at Belle

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

First search for B→Xs​ννˉ decays

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

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

Determination of ∣Vub​∣ from simultaneous measurements of untagged B0→π−ℓ+νℓ​ and B+→ρ0ℓ+νℓ​ decays

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

Search for lepton-flavor-violating τ−→ℓ−ϕ decays in 2019-2021 Belle II data

Observation of B→D(∗)K−KS0​ decays using the 2019-2022 Belle II data sample

Measured and projected beam backgrounds in the Belle II experiment at the SuperKEKB collider

Measurement of the B0→D∗−ℓ+νℓ​ branching ratio and ∣Vcb​∣ with a fully reconstructed accompanying B meson in 2019-2021 Belle II data

A test of light-lepton universality in the rates of inclusive semileptonic B-meson decays at Belle II

Search for an invisible Z′ in a final state with two muons and missing energy at Belle II

Determination of ∣Vub​∣ from untagged B0→π−ℓ+νℓ​ decays using 2019-2021 Belle II data

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 $B^{0} \to π^{0} π^{0}$

Search for the decay $B^{+} \to K^{+} τ^{+} τ^{-}$ using data from the Belle and Belle II experiments

Study of $e^{+} e^{-} \to π^{+} π^{-} Υ (1 D)$ at Belle II

A search for feebly-interacting particles in $B$ decays with missing energy at Belle

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

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

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

Determination of $∣ V_{u b} ∣$ from simultaneous measurements of untagged $B^{0} \to π^{-} ℓ^{+} ν_{ℓ}$ and $B^{+} \to ρ^{0} ℓ^{+} ν_{ℓ}$ decays

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

Search for lepton-flavor-violating $τ^{-} \to ℓ^{-} ϕ$ decays in 2019-2021 Belle II data

Observation of $B \to D^{(*)} K^{-} K_{S}^{0}$ decays using the 2019-2022 Belle II data sample

Measurement of the $B^{0} \to D^{*-} ℓ^{+} ν_{ℓ}$ branching ratio and $∣ V_{c b} ∣$ with a fully reconstructed accompanying $B$ meson in 2019-2021 Belle II data

A test of light-lepton universality in the rates of inclusive semileptonic $B$ -meson decays at Belle II

Search for an invisible $Z^{'}$ in a final state with two muons and missing energy at Belle II

Determination of $∣ V_{u b} ∣$ from untagged $B^{0} \to π^{-} ℓ^{+} ν_{ℓ}$ decays using 2019-2021 Belle II data