A5101421302- Particle physics theoretical and experimental studies
- Quantum Chromodynamics and Particle Interactions
- High-Energy Particle Collisions Research
- Neutrino Physics Research
- Dark Matter and Cosmic Phenomena
- Particle Detector Development and Performance
- Particle Accelerators and Free-Electron Lasers
- Computational Physics and Python Applications
- Medical Imaging Techniques and Applications
- Atomic and Subatomic Physics Research
- Black Holes and Theoretical Physics
- Cosmology and Gravitation Theories
- Superconducting Materials and Applications
- Radiation Detection and Scintillator Technologies
- Nuclear physics research studies
- Advanced Data Storage Technologies
- Scientific Computing and Data Management
- Distributed and Parallel Computing Systems
- Stochastic processes and statistical mechanics
- Astrophysics and Cosmic Phenomena
- Gamma-ray bursts and supernovae
- Theoretical and Computational Physics
- International Science and Diplomacy
- Calibration and Measurement Techniques
- Atmospheric Ozone and Climate
Deutsches Elektronen-Synchrotron DESY
2021-2023
Imperial College London
2023
University of Utah
2023
University of British Columbia
2019-2022
Campbell Collaboration
2013-2022
University of Mississippi
2016-2020
Novosibirsk State Technical University
2014-2020
Institute of Particle Physics
2020
Universitat de Barcelona
2018-2020
Centre National de la Recherche Scientifique
2015-2018
The experimental results on the ratios of branching fractions R(D)=B(B[over ¯]→Dτ^{-}ν[over ¯]_{τ})/B(B[over ¯]→Dℓ^{-}ν[over ¯]_{ℓ}) and R(D^{*})=B(B[over ¯]→D^{*}τ^{-}ν[over ¯]→D^{*}ℓ^{-}ν[over ¯]_{ℓ}), where ℓ denotes an electron or a muon, show long-standing discrepancy with standard model predictions, might hint at violation lepton flavor universality. We report new simultaneous measurement R(D) R(D^{*}), based data sample containing 772×10^{6} BB[over ¯] events recorded ϒ(4S) resonance...
We search for the rare decay <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:msup><a:mi>B</a:mi><a:mo>+</a:mo></a:msup><a:mo stretchy="false">→</a:mo><a:msup><a:mi>K</a:mi><a:mo>+</a:mo></a:msup><a:mi>ν</a:mi><a:mover accent="true"><a:mi>ν</a:mi><a:mo stretchy="false">¯</a:mo></a:mover></a:math> in a <f:math xmlns:f="http://www.w3.org/1998/Math/MathML" display="inline"><f:mn>362</f:mn><f:mtext> </f:mtext><f:mtext>...
We present a search for the direct production of light pseudoscalar decaying into two photons with Belle II detector at SuperKEKB collider. process e^{+}e^{-}→γa, a→γγ in mass range 0.2<m_{a}<9.7 GeV/c^{2} using data corresponding to an integrated luminosity (445±3) pb^{-1}. Light pseudoscalars interacting predominantly standard model gauge bosons (so-called axionlike particles or ALPs) are frequently postulated extensions model. find no evidence ALPs and set 95% confidence level upper...
The full event interpretation is presented: a new exclusive tagging algorithm used by the high-energy physics experiment Belle II. experimental setup of II allows precise measurement otherwise inaccessible B meson decay modes. Full Event Interpretation enables many these measurements. relies on machine learning to automatically identify plausible chains based data recorded detector. Compared similar algorithms employed previous experiments, provides greater efficiency, yielding larger...
A search for the flavor-changing neutral-current decay B^{+}→K^{+}νν[over ¯] is performed at Belle II experiment SuperKEKB asymmetric energy electron-positron collider. The data sample corresponds to an integrated luminosity of 63 fb^{-1} collected ϒ(4S) resonance and a 9 60 MeV below resonance. Because measurable signature involves only single charged kaon, novel measurement approach used that exploits not properties decay, but also inclusive other B meson in ϒ(4S)→BB[over event, suppress...
Abstract A series of data samples was collected with the Belle II detector at SuperKEKB collider from March 2019 to June 2022. We determine integrated luminosities these using three distinct methodologies involving Bhabha ( ), digamma and dimuon ) events. The total luminosity obtained Bhabha, digamma, events is (426.88 ± 0.03 2.61) fb −1 , (429.28 2.62) (423.99 0.04 3.83) where first uncertainties are statistical second systematic. resulting combination methods (427.87 2.01) .
We measure the time-integrated <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mi>C</a:mi><a:mi>P</a:mi></a:math> asymmetry in <c:math xmlns:c="http://www.w3.org/1998/Math/MathML" display="inline"><c:msup><c:mi>D</c:mi><c:mn>0</c:mn></c:msup><c:mo stretchy="false">→</c:mo><c:msubsup><c:mi>K</c:mi><c:mi>S</c:mi><c:mn>0</c:mn></c:msubsup><c:msubsup><c:mi>K</c:mi><c:mi>S</c:mi><c:mn>0</c:mn></c:msubsup></c:math> decays reconstructed <f:math...
We measure the branching fraction of decay <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mrow><a:msup><a:mrow><a:mi>B</a:mi></a:mrow><a:mrow><a:mn>0</a:mn></a:mrow></a:msup><a:mo stretchy="false">→</a:mo><a:mi>J</a:mi><a:mo>/</a:mo><a:mi>ψ</a:mi><a:mi>ω</a:mi></a:mrow></a:math> using data collected with Belle II detector at SuperKEKB collider. The contain <d:math xmlns:d="http://www.w3.org/1998/Math/MathML" display="inline"><d:mrow><d:mo...
A bstract Using data samples of 983.0 fb − 1 and 427.9 accumulated with the Belle II detectors operating at KEKB SuperKEKB asymmetric-energy e + colliders, singly Cabibbo-suppressed decays $$ {\Xi}_c^{+}\to p{K}_S^0 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msubsup> <mml:mi>Ξ</mml:mi> <mml:mi>c</mml:mi> <mml:mo>+</mml:mo> </mml:msubsup> <mml:mo>→</mml:mo> <mml:mi>p</mml:mi> <mml:mi>K</mml:mi> <mml:mi>S</mml:mi> <mml:mn>0</mml:mn> </mml:math> , \Lambda {\pi}^{+}...
We report the first measurement of $D^{\ast -}$ meson polarization in decay $B^0 \to D^{*-} \tau^+\nu_{\tau}$ using full data sample 772$\times 10^6$ $B\bar{B}$ pairs recorded with Belle detector at KEKB electron-positron collider. Our result, $F_L^{D^\ast} = 0.60 \pm 0.08 ({\rm stat}) 0.04 sys})$, where $F_L^{D^\ast}$ denotes $D^{\ast-}$ longitudinal fraction, agrees within about $1.7$ standard deviations model prediction.
Theories beyond the standard model often predict existence of an additional neutral boson, $Z^{\prime}$. Using data collected by Belle II experiment during 2018 at SuperKEKB collider, we perform first searches for invisible decay a $Z^{\prime}$ in process $e^+ e^- \to \mu^+ \mu^- Z^{\prime}$ and lepton-flavor-violating e^{\pm} \mu^{\mp} Z^{\prime}$. We do not find any excess events set 90\% credibility level upper limits on cross sections these processes. translate former, framework...
Abstract We report on new flavor tagging algorithms developed to determine the quark-flavor content of bottom ( "Image missing"<!-- image only, no MathML or LaTex -->) mesons at Belle II. The provide essential inputs for measurements mixing and charge-parity violation. validate evaluate performance using hadronic --> decays with flavor-specific final states reconstructed in a data set corresponding an integrated luminosity 62.8 fb $$^{-1}$$ <mml:math...
Belle II is an experiment operating at the intensity frontier. Over next decades, it will record decay of billions bottom mesons, charm hadrons, and tau leptons produced in 10 GeV electron-positron collisions SuperKEKB high-luminosity collider KEK. These data, collected low-background kinematically known conditions, allow us to measure hundreds parameters that test standard model (SM) probe for existence new particles, mass scales orders magnitudes higher than those studied energy We project...
We present the first measurement of ratio branching fractions inclusive semileptonic B-meson decays, R(X_{e/μ})=B(B→Xeν)/B(B→Xμν), a precision test electron-muon universality, using data corresponding to 189 fb^{-1} from electron-positron collisions collected with Belle II detector. In events where partner B meson is fully reconstructed, we use fits lepton momentum spectra above 1.3 GeV/c obtain R(X_{e/μ})=1.007±0.009(stat)±0.019(syst), which most precise lepton-universality its kind and...
We search for lepton-flavor-violating τ^{-}→e^{-}α and τ^{-}→μ^{-}α decays, where α is an invisible spin-0 boson. The uses electron-positron collisions at 10.58 GeV center-of-mass energy with integrated luminosity of 62.8 fb^{-1}, produced by the SuperKEKB collider collected Belle II detector. excess in lepton-energy spectrum known τ^{-}→e^{-}ν[over ¯]_{e}ν_{τ} τ^{-}→μ^{-}ν[over ¯]_{μ}ν_{τ} decays. report 95% confidence-level upper limits on branching-fraction ratio...
The $L_{\mu}-L_{\tau}$ extension of the standard model predicts existence a lepton-flavor-universality-violating $Z^{\prime}$ boson that couples only to heavier lepton families. We search for such $Z^\prime$ through its invisible decay in process $e^+ e^- \to \mu^+ \mu^- Z^{\prime}$. use sample electron-positron collisions at center-of-mass energy 10.58GeV collected by Belle II experiment 2019-2020, corresponding an integrated luminosity 79.7fb$^{-1}$. find no excess over expected...
We present a measurement of the τ-lepton mass using sample about 175 million e+e−→τ+τ− events collected with Belle II detector at SuperKEKB e+e− collider center-of-mass energy 10.579 GeV. This corresponds to an integrated luminosity 190 fb−1. use kinematic edge τ pseudomass distribution in decay τ−→π−π+π−ντ and measure be 1777.09±0.08±0.11 MeV/c2, where first uncertainty is statistical second systematic. result most precise date.Received 31 May 2023Accepted 13 July...
We determine the Cabibbo-Kobayashi-Maskawa matrix-element magnitude |Vcb| using B¯0→D*+ℓ−ν¯ℓ decays reconstructed in 189 fb−1 of collision data collected by Belle II experiment, located at SuperKEKB e+e− collider. Partial decay rates are reported as functions recoil parameter w and three angles separately for electron muon final states. obtain Boyd-Grinstein-Lebed Caprini-Lellouch-Neubert parametrizations, find |Vcb|BGL=(40.57±0.31±0.95±0.58)×10−3 |Vcb|CLN=(40.13±0.27±0.93±0.58)×10−3 with...
We report measurements of time-dependent <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mrow><a:mi>C</a:mi><a:mi>P</a:mi></a:mrow></a:math> asymmetries in <c:math xmlns:c="http://www.w3.org/1998/Math/MathML" display="inline"><c:msup><c:mi>B</c:mi><c:mn>0</c:mn></c:msup><c:mo stretchy="false">→</c:mo><c:msubsup><c:mi>K</c:mi><c:mi>S</c:mi><c:mn>0</c:mn></c:msubsup><c:msup><c:mi>π</c:mi><c:mn>0</c:mn></c:msup><c:mi>γ</c:mi></c:math> decays based on a data sample...
We present a measurement of the branching fraction and time-dependent charge-parity (<a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mi>C</a:mi><a:mi>P</a:mi></a:math>) decay-rate asymmetries in <c:math xmlns:c="http://www.w3.org/1998/Math/MathML" display="inline"><c:msup><c:mi>B</c:mi><c:mn>0</c:mn></c:msup><c:mo stretchy="false">→</c:mo><c:mrow><c:mi>J</c:mi><c:mo>/</c:mo><c:mi>ψ</c:mi></c:mrow><c:msup><c:mi>π</c:mi><c:mn>0</c:mn></c:msup></c:math> decays. The data...
Abstract From April to July 2018, a data sample at the peak energy of resonance was collected with Belle II detector SuperKEKB electron-positron collider. This is first experiment. Using Bhabha and digamma events, we measure integrated luminosity be ( , where uncertainty statistical second systematic. work provides basis for future measurements II.
A study of the two-body decays B^{±}→X_{cc[over ¯]}K^{±}, where X_{cc[over ¯]} refers to one charmonium state, is reported by BABAR Collaboration using a data sample 424 fb^{-1}. The absolute determination branching fractions for these are significantly improved compared previous measurements. Evidence found decay B^{+}→X(3872)K^{+} at 3σ level. fraction B[B^{+}→X(3872)K^{+}]=[2.1±0.6(stat)±0.3(syst)]×10^{-4} measured first time. It follows that B[X(3872)→J/ψπ^{+}π^{-}]=(4.1±1.3)%,...
We study the processes $\gamma \gamma \to \eta_c \eta' K^+ K^-$, $\eta' \pi^+ \pi^-$, and $\eta \pi^-$ using a data sample of 519 $fb^{-1}$ recorded with BaBar detector operating at SLAC PEP-II asymmetric-energy $e^+e^-$ collider center-of-mass energies near $\Upsilon(nS)$ ($n = 2,3,4$) resonances. This is first observation decay $\eta_c K^-$ we measure branching fraction $\Gamma(\eta_c K^-)/(\Gamma(\eta_c \pi^-)=0.644\pm 0.039_{\rm stat}\pm 0.032_{\rm sys}$. Significant interference...
We present measurements of the first to fourth moments lepton mass squared q2 B→Xcℓ¯νℓ decays for ℓ=e, μ and with Xc a hadronic system containing charm quark. These results use sample electron-positron collisions at Υ(4S) resonance corresponding 62.8 fb−1 integrated luminosity collected by Belle II 2 experiment in 2019 2020. To identify reconstruct q2, one B mesons from an Υ(4S)→B¯B decay is fully reconstructed mode using multivariate tagging algorithm. report raw central q2>1.5 GeV2/c4 up...