K. Yu. Todyshev
A5087518170- 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
- Medical Imaging Techniques and Applications
- Atomic and Subatomic Physics Research
- Superconducting Materials and Applications
- Black Holes and Theoretical Physics
- Radiation Detection and Scintillator Technologies
- Computational Physics and Python Applications
- Nuclear physics research studies
- Cosmology and Gravitation Theories
- Advanced Data Storage Technologies
- Astrophysics and Cosmic Phenomena
- Atomic and Molecular Physics
- Nuclear Physics and Applications
- Distributed and Parallel Computing Systems
- Radiation Therapy and Dosimetry
- Particle accelerators and beam dynamics
- Stochastic processes and statistical mechanics
- Lanthanide and Transition Metal Complexes
- Nuclear reactor physics and engineering
Budker Institute of Nuclear Physics
2015-2024
Novosibirsk State University
2015-2024
Siberian Branch of the Russian Academy of Sciences
2013-2022
Campbell Collaboration
2009-2022
University of Sassari
2020
Istituto Nazionale di Fisica Nucleare, Sezione di Bologna
2020
University of Bologna
2020
University of California, Irvine
2020
Boreskov Institute of Catalysis
2019
Novosibirsk State Technical University
2014
Based on the full BABAR data sample, we report improved measurements of ratios R(D(*))=B(B[over ¯]→D(*)τ(-)ν[over ¯](τ))/B(B[over ¯]→D(*)ℓ(ℓ)(-)ν[over ¯](ℓ)), where ℓ is either e or μ. These are sensitive to new physics contributions in form a charged Higgs boson. We measure R(D)=0.440±0.058±0.042 and R(D(*))=0.332±0.024±0.018, which exceed standard model expectations by 2.0σ 2.7σ, respectively. Taken together, our results disagree with these at 3.4σ level. This excess cannot be explained...
Based on the full BaBar data sample, we report improved measurements of ratios R(D(*)) = B(B -> D(*) Tau Nu)/B(B l Nu), where is either e or mu. These are sensitive to new physics contributions in form a charged Higgs boson. We measure R(D) 0.440 +- 0.058 0.042 and R(D*) 0.332 0.024 0.018, which exceed Standard Model expectations by 2.0 sigma 2.7 sigma, respectively. Taken together, our results disagree with these at 3.4 level. This excess cannot be explained boson type II two-Higgs-doublet...
Searches for lepton-flavor-violating decays of a tau lepton to lighter mass and photon have been performed with the entire data set (963+/-7)x10{6} collected by BABAR detector near Upsilon(4S), Upsilon(3S) Upsilon(2S) resonances. The searches yield no evidence signals we upper limits on branching fractions B(tau{+/-}-->e{+/-}gamma)<3.3x10{-8} B(tau{+/-}-->mu{+/-}gamma)<4.4x10{-8} at 90% confidence level.
Dark sectors charged under a new Abelian interaction have recently received much attention in the context of dark matter models. These models introduce light mediator, so-called photon (A′), connecting sector to standard model. We present search for reaction e+e−→γA′, A′→e+e−, μ+μ− using 514 fb−1 data collected with BABAR detector. observe no statistically significant deviations from model predictions, and we set 90% confidence level upper limits on mixing strength between at 10−4−10−3...
We study the reaction e+e−→e+e−π0 in single tag mode and measure differential cross section dσ/dQ2 γγ∗→π0 transition form factor momentum transfer range from 4 to 40 GeV2. At Q2>10 GeV2 measured exceeds asymptotic limit predicted by perturbative QCD. The analysis is based on 442 fb−1 of integrated luminosity collected at PEP-II with BABAR detector e+e− center-of-mass energies near 10.6 GeV.16 MoreReceived 29 May 2009DOI:https://doi.org/10.1103/PhysRevD.80.052002©2009 American Physical Society
We search for single-photon events in 53 fb−1 of e+e− collision data collected with the BABAR detector at PEP-II B-Factory. look a single high-energy photon and large missing momentum energy, consistent production spin-1 particle A′ through process e+e−→γA′; A′→invisible. Such particles, referred to as "dark photons," are motivated by theories applying U(1) gauge symmetry dark matter. find no evidence such processes set 90% confidence level upper limits on coupling strength mass range mA′≤8...
A precise measurement of the cross section process e+ e- to pi+ pi- (gamma) from threshold an energy 3 GeV is obtained with initial state radiation (ISR) method using 232 fb^-1 data collected BABAR detector at center-of-mass energies near 10.6 GeV. The ISR luminosity determined a study leptonic mu+ mu- gamma (gamma). leading-order hadronic contribution muon magnetic anomaly calculated pi measured 1.8 (514.1 +-2.2(stat} +-3.1(syst}) x 10^{-10}.
Many models of physics beyond the Standard Model predict existence new Abelian forces with gauge bosons mediating interactions between "dark sectors" and Model. We report a search for dark boson Z' coupling only to second third generations leptons in reaction e+e- -> mu+mu- Z', using 514 fb-1 data collected by BABAR experiment. No significant signal is observed masses range 0.212 - 10 GeV. Limits on parameter g' as low 7x10^-4 are derived, leading improvements bounds compared those...
We present a measurement of the cross section process e(+)e(-)-->pi(+)pi(-)psi(2S) from threshold up to 8 GeV center-of-mass energy using events containing initial-state radiation, produced at SLAC PEP-II e(+)e(-) storage rings. The study is based on 298 fb(-1) data recorded with BABAR detector. A structure observed in not far above threshold, near 4.32 GeV. also investigate compatibility this Y(4260) previously reported by experiment.
A precise measurement of the cross section process $e^+e^-\toπ^+π^-(γ)$ from threshold to an energy 3GeV is obtained with initial-state radiation (ISR) method using 232fb$^{-1}$ data collected BaBar detector at $e^+e^-$ center-of-mass energies near 10.6GeV. The ISR luminosity determined a study leptonic $e^+e^-\toμ^+μ^-(γ)γ_{\rm ISR}$, which found agree next-to-leading-order QED prediction within 1.1%. for systematic uncertainty 0.5% in dominant $ρ$ resonance region. leading-order hadronic...
In a sample of $471\ifmmode\times\else\texttimes\fi{}{10}^{6}$ $B\overline{B}$ events collected with the BABAR detector at PEP-II ${e}^{+}{e}^{\ensuremath{-}}$ collider we study rare decays $B\ensuremath{\rightarrow}{K}^{(*)}{\ensuremath{\ell}}^{+}{\ensuremath{\ell}}^{\ensuremath{-}}$, where ${\ensuremath{\ell}}^{+}{\ensuremath{\ell}}^{\ensuremath{-}}$ is either or ${\ensuremath{\mu}}^{+}{\ensuremath{\mu}}^{\ensuremath{-}}$. We report results on partial branching fractions and isospin...
This paper reports measurements of processes: e+e−→γKS0K±π∓, e+e−→γK+K−π0, e+e−→γϕη, and e+e−→γϕπ0. The initial-state radiated photon allows to cover the hadronic final state in energy range from thresholds up ≈4.6 GeV. overall size data sample analyzed is 232 fb−1, collected by BABAR detector running at PEP-II e+e− storage ring. From Dalitz plot analysis KS0K±π∓ state, moduli, relative phase isoscalar isovector components e+e−→KK*(892) cross section are determined. Parameters ϕ ρ...
We search for the flavor-changing neutral-current decays $B\ensuremath{\rightarrow}{K}^{(*)}\ensuremath{\nu}\overline{\ensuremath{\nu}}$, and invisible $J/\ensuremath{\psi}\ensuremath{\rightarrow}\ensuremath{\nu}\overline{\ensuremath{\nu}}$ $\ensuremath{\psi}(2S)\ensuremath{\rightarrow}\ensuremath{\nu}\overline{\ensuremath{\nu}}$ via $B\ensuremath{\rightarrow}{K}^{(*)}J/\ensuremath{\psi}$ $B\ensuremath{\rightarrow}{K}^{(*)}\ensuremath{\psi}(2S)$, respectively, using a data sample of...
We present measurements of the flavor-changing neutral current decays B --> Kl+l- and K*l+l-, where l+l- is either an e+e- or mu+mu- pair. The data sample comprises 229 x 10^6 Y(4s) -->to BBbar collected with BaBar detector at PEP-II storage ring. Flavor-changing are highly suppressed in Standard Model their predicted properties could be significantly modified by new physics electroweak scale. measure branching fractions B(B Kll) = (0.34 +- 0.07 0.02) 10^{-6}, K*ll) (0.78^{+0.19}_{-0.17}...
We present a study of the decays B^{0,+} --> J/psi pi^+ pi^- pi^0 K^{0,+}, using 467 10^6 BBbar pairs recorded with BABAR detector. evidence for decay mode X(3872) omega, product branching fractions B(B^+ X(3872)K^+) B(X(3872) omega) =[0.6\pm0.2\stat \pm 0.1\syst ] 10^{-5}, and B(B^0 X(3872)K^0) =[0.6\pm0.3\stat 10^{-5}. A detailed mass distribution from favors negative-parity assignment.
In a search for $B\ensuremath{\rightarrow}c\overline{c}\ensuremath{\gamma}K$ decays with the BABAR detector, where $c\overline{c}$ includes $J/\ensuremath{\psi}$ and $\ensuremath{\psi}(2S)$, $K$ ${K}^{\ifmmode\pm\else\textpm\fi{}}$, ${K}_{S}^{0}$, ${K}^{*}(892)$, we find evidence $X(3872)\ensuremath{\rightarrow}J/\ensuremath{\psi}\ensuremath{\gamma}$ $X(3872)\ensuremath{\rightarrow}\ensuremath{\psi}(2S)\ensuremath{\gamma}$ $3.6\ensuremath{\sigma}$ $3.5\ensuremath{\sigma}$ significance,...
We search for evidence of a light scalar boson in the radiative decays Upsilon(2S) and Upsilon(3S) resonances: Upsilon(2S,3S)-->gammaA0, A0-->mu+mu-. Such particle appears extensions standard model, where CP-odd Higgs naturally couples strongly to b quarks. find no such processes mass range 0.212 < or = mA0 9.3 GeV samples 99 x 10(6) 122 collected by BABAR detector at SLAC PEP-II B factory set stringent upper limits on effective coupling quark A0. also limit dimuon branching fraction etab...
We study the processes e+e−→2(π+π−)π0γ, 2(π+π−)ηγ, K+K−π+π−π0γ and K+K−π+π−ηγ with hard photon radiated from initial state. About 20 000, 4300, 5500, 375 fully reconstructed events, respectively, are selected 232 fb−1 of BABAR data. The invariant mass hadronic final state defines effective e+e− center-of-mass energy, so that obtained cross sections threshold to about 5 GeV can be compared corresponding direct measurements, currently available only for ηπ+π− ωπ+π− submodes e+e−→2(π+π−)π0...
We search for the production of doubly charmed baryons in e+e− annihilations at or near a center-of-mass energy 10.58 GeV, data sample with an integrated luminosity 232 fb−1 recorded BABAR detector PEP-II storage ring Stanford Linear Accelerator Center. Ξ+cc final states Λ+cK−π+ and Ξ0cπ+, Ξ++cc Λ+cK−π+π+ Ξ0cπ+π+. find no evidence baryons.Received 18 May 2006DOI:https://doi.org/10.1103/PhysRevD.74.011103©2006 American Physical Society
We present a study of the decays B0,+→J/ψωK0,+ using 383×106 B¯¯¯B events obtained with BABAR detector at PEP-II. observe Y(3940)→J/ψω, mass 3914.6+3.8−3.4(stat)±2.0(syst) MeV/c2, and width 34+12−8(stat)±5(syst) MeV. The ratio B0 B+ decay to YK is 0.27+0.28−0.23(stat)+0.04−0.01(syst), relevant branching fractions are reported.Received 14 November 2007DOI:https://doi.org/10.1103/PhysRevLett.101.082001©2008 American Physical Society
We report the results of a search for bottomonium ground state eta_b(1S) in photon energy spectrum with sample (109 +/- 1) million Upsilon(3S) recorded at BABAR detector PEP-II B factory SLAC. observe peak E_gamma = 921.2 {+2.1} {-2.8} (stat) 2.4(syst) MeV significance 10 standard deviations. interpret observed as being due to monochromatic photons from radiative transition -> gamma eta_b(1S). This corresponds an mass $9388.9 {+3.1} {-2.3} 2.7(syst) MeV/c2. The hyperfine...
The process e+e- --> p anti-p gamma is studied using 469 fb-1 of integrated luminosity collected with the BABAR detector at PEP-II collider, an center-of-mass energy 10.6 GeV. From analysis invariant mass spectrum, dependence cross section for measured from threshold to 4.5 ratio electric and magnetic form factors, |G_E/G_M|, asymmetry in proton angular distribution are masses below 3 We also measure branching fractions decays J/psi psi(2S) anti p.
We report the results of a search for $Z(4430)^-$ decay to $J/\psi\pi^-$ or $\psi(2S)\pi^-$ in $B^{-,0}\to \jpsi\pi^- K^{0,+}$ and \psitwos \pi^- decays. The data were collected with BABAR detector at SLAC PEP-II asymmetric-energy $e^+e^-$ collider operating center mass energy 10.58 \gev, sample corresponds an integrated luminosity 413 fb$^{-1}$. Each $K\pi$ distribution exhibits clear $K^{\ast}(892)$ $K^{\ast}_2(1430)$ signals, efficiency-corrected spectrum is well-described by...
We present a study of resonances in exclusive decays $B$ mesons to ${\overline{D}}^{(*)}{D}^{(*)}K$. report the observation $B\ensuremath{\rightarrow}{\overline{D}}^{(*)}{D}_{s1}^{+}(2536)$ where ${D}_{s1}^{+}(2536)$ is reconstructed ${D}^{*0}{K}^{+}$ and ${D}^{*+}{K}_{S}^{0}$ decay channels. also $B\ensuremath{\rightarrow}\ensuremath{\psi}(3770)K$ $\ensuremath{\psi}(3770)$ ${\overline{D}}^{0}{D}^{0}$ ${D}^{\ensuremath{-}}{D}^{+}$. In addition, we an enhancement for...
Although CP violation in the B meson system has been well established by factories, there no direct observation of time-reversal violation. The decays entangled neutral mesons into definite flavor states (B(0) or B(0)), and J/ψK(L)(0) ccK(S)(0) final (referred to as B(+) B(-)), allow comparisons between probabilities four pairs T-conjugated transitions, for example, B(0) → B(-) B(0), a function time difference two decays. Using 468 × 10(6) BB produced Υ(4S) collected BABAR detector at SLAC,...