Yu. Onishchuk
A5102874030- 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
- Radiation Detection and Scintillator Technologies
- Astrophysics and Cosmic Phenomena
- Nuclear Physics and Applications
- Superconducting Materials and Applications
- Computational Physics and Python Applications
- Particle Accelerators and Free-Electron Lasers
- Nuclear reactor physics and engineering
- Atomic and Subatomic Physics Research
- Advanced NMR Techniques and Applications
- Graphite, nuclear technology, radiation studies
- Black Holes and Theoretical Physics
- Noncommutative and Quantum Gravity Theories
- Radioactivity and Radon Measurements
- Nuclear physics research studies
- NMR spectroscopy and applications
- Laser-induced spectroscopy and plasma
- Radioactive contamination and transfer
- Scientific Computing and Data Management
- Medical Imaging Techniques and Applications
Taras Shevchenko National University of Kyiv
2015-2024
Istituto Nazionale di Fisica Nucleare, Sezione di Bologna
2014-2016
The Ohio State University
2011
Tel Aviv University
2010-2011
Institute for Nuclear Research
2010-2011
University of the Aegean
2010-2011
The University of Tokyo
2010
Tokyo Institute of Technology
2010
Tokyo Metropolitan University
2010
Istituto Nazionale di Fisica Nucleare, Sezione di Torino
2010
Two-particle azimuthal correlations have been measured in neutral current deep inelastic ep scattering with virtuality Q2> 5 GeV2 at a centre-of-mass energy $$ \sqrt{s} = 318 GeV recorded the ZEUS detector HERA. The of charged particles range laboratory pseudorapidity −1.5 < η 2.0 and transverse momentum 0.1 pT< 5.0 event multiplicities Nch up to six times larger than average 〈Nch〉 ≈ 5. two-particle terms angular observables cn{2} 〈〈cosnΔφ〉〉, where n is between 1 4 ∆φ relative angle two...
The high-precision HERA data allows searches up to TeV scales for beyond the Standard Model contributions electron–quark scattering. Combined measurements of inclusive deep inelastic cross sections in neutral and charged current ep scattering corresponding a luminosity around 1 fb−1 have been used this analysis. A new approach analysis is presented; simultaneous fits parton distribution functions together with "new physics" processes were performed. Results are presented considering finite...
The azimuthal correlation angle, $\Delta\phi$, between the scattered lepton and leading jet in deep inelastic $e^{\pm}p$ scattering at HERA has been studied using data collected with ZEUS detector a centre-of-mass energy of $\sqrt{s} = 318 \;\mathrm{GeV}$, corresponding to an integrated luminosity $326 \;\mathrm{pb}^{-1}$. A measurement cross sections laboratory frame was made fiducial region photon virtuality $10 \;\mathrm{GeV}^2 < Q^2 350 \;\mathrm{GeV}^2$, inelasticity $0.04 y 0.7$,...
Abstract A new measurement of inclusive-jet cross sections in the Breit frame neutral current deep inelastic scattering using ZEUS detector at HERA collider is presented. The data were taken years 2004–2007 a centre-of-mass energy $$318\,\,\textrm{GeV}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mn>318</mml:mn> <mml:mspace/> <mml:mtext>GeV</mml:mtext> </mml:mrow> </mml:math> and correspond to an integrated luminosity $$347\,\,\textrm{pb}^{-1}$$...
Production of exclusive dijets in diffractive deep inelastic $$e^\pm p$$ scattering has been measured with the ZEUS detector at HERA using an integrated luminosity 372 pb $$^{-1}$$ . The measurement was performed for $$\gamma ^{*}$$ –p centre-of-mass energies range $$90< W < {250}\,{\mathrm{GeV}}$$ and photon virtualities $$Q^2 > {25}\,{\mathrm{GeV}^{2}}$$ Energy flows around jet axis are presented. cross section is presented as a function $$\beta $$ $$\phi , where =x/x_\mathrm{I\!P}$$ x...
High-precision HERA data corresponding to a luminosity of around $1\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ have been used in the framework $eeqq$ contact interactions (CI) set limits on possible high-energy contributions beyond Standard Model electron-quark scattering. Measurements inclusive deep inelastic cross sections neutral and charged current $ep$ scattering were considered. The analysis has based simultaneous fits parton distribution functions including CI couplings Several...
A simultaneous fit of parton distribution functions (PDFs) and electroweak parameters to HERA data on deep inelastic scattering is presented. The input are the neutral current charged inclusive cross sections which were previously used in QCD analysis leading HERAPDF2.0 PDFs. In addition, polarization electron beam was taken into account for ZEUS recorded between 2004 2007. Results vector axial-vector couplings $Z$ boson $u$- $d$-type quarks, value mixing angle mass $W$ values obtained...
The exclusive deep inelastic electroproduction of ψ(2S) and J/ψ(1S) at an ep centre-of-mass energy 317 GeV has been studied with the ZEUS detector HERA in kinematic range 2<Q2<80 GeV2, 30<W<210 |t|<1 where Q2 is photon virtuality, W photon–proton t squared four-momentum transfer proton vertex. data for 2<Q2<5 GeV2 were taken I running period correspond to integrated luminosity 114 pb−1. 5<Q2<80 are from both II periods 468 decay modes analysed μ+μ− J/ψ(1S)π+π− J/ψ(1S). cross-section ratio...
At large values of $x$, the parton distribution functions (PDFs) proton are poorly constrained and there considerable variations between different global fits. Data at such high $x$ have already been published by ZEUS Collaboration, but not yet used in PDF extractions. A technique for comparing predictions based on sets to observed number events data is presented. It applied compare from most commonly PDFs Bjorken $x$. wide variation found ability predict results. scheme including high-$x$...
The exclusive photoproduction reactions $\gamma p \to J/\psi(1S) p$ and \psi(2S) have been measured at an $ep$ centre-of-mass energy of 318 GeV with the ZEUS detector HERA using integrated luminosity 373 pb$^{-1}$. measurement was made in kinematic range $30 < W 180$ GeV, $Q^2 1$ GeV$^2$ $|t| GeV$^2$, where $W$ is photon--proton energy, $Q^2$ photon virtuality $t$ squared four-momentum transfer proton vertex. decay channels used were $J/\psi(1S) \mu^+ \mu^-$, $\psi(2S) \mu^-$ \pi^+ \pi^-$...
Lorentz and $CPT$ symmetry in the quark sector of Standard Model are studied context an effective field theory using ZEUS ${e}^{\ifmmode\pm\else\textpm\fi{}}p$ data. Symmetry-violating effects can lead to time-dependent oscillations otherwise time-independent observables, including scattering cross sections. An analysis five years inclusive neutral-current deep inelastic events corresponding integrated HERA luminosity $372\text{ }\text{ }{\mathrm{pb}}^{\ensuremath{-}1}$ at...
A bstract Collective behaviour of final-state hadrons, and multiparton interactions are studied in high-multiplicity ep scattering at a centre-of-mass energy $$ \sqrt{s} <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msqrt> <mml:mi>s</mml:mi> </mml:msqrt> </mml:math> = 318 GeV with the ZEUS detector HERA. Two- four-particle azimuthal correlations, as well multiplicity, transverse momentum, pseudorapidity distributions for charged-particle multiplicities N ch ≥ 20 measured....
A bstract Charm production in charged current deep inelastic scattering has been measured for the first time e ± p collisions, using data collected with ZEUS detector at HERA, corresponding to an integrated luminosity of 358 pb −1 . Results are presented separately + and − a centre-of-mass energy $$ \sqrt{s} <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msqrt> <mml:mi>s</mml:mi> </mml:msqrt> </mml:math> = 318 GeV within kinematic phase-space region 200 2 < Q 60000 y 0.9,...
A simultaneous fit of parton distribution functions (PDFs) and electroweak parameters to HERA data on deep inelastic scattering is presented. The input are the neutral current charged inclusive cross sections which were previously used in QCD analysis leading HERAPDF2.0 PDFs. In addition, polarisation electron beam was taken into account for ZEUS recorded between 2004 2007. Results vector axial-vector couplings Z boson u- d-type quarks, value mixing angle mass W values obtained agreement...
The photoproduction of isolated photons has been measured in diffractive events recorded by the ZEUS detector at HERA. Cross sections are evaluated photon transverse-energy and pseudorapidity ranges $5<{E}_{T}^{\ensuremath{\gamma}}<15\text{ }\text{ }\mathrm{GeV}$ $\ensuremath{-}0.7<{\ensuremath{\eta}}^{\ensuremath{\gamma}}<0.9$, inclusively, also with a jet transverse energy $4<{E}_{T}^{\text{jet}}<35\text{ $\ensuremath{-}1.5<{\ensuremath{\eta}}^{\text{jet}}<1.8$, using total integrated...
A search for a narrow baryonic state in the $pK^0_S$ and $\bar{p}K^0_S$ system has been performed $ep$ collisions at HERA with ZEUS detector using an integrated luminosity of 358 pb$^{-1}$ taken 2003-2007. The was deep inelastic scattering events centre-of-mass energy 318 GeV exchanged photon virtuality, $Q^2$, between 20 100 $\rm{} GeV^{2}$. Contrary to evidence presented such around 1.52 previous analysis sample 121 1996-2000, no resonance peak found $p(\bar{p})K^0_S$ invariant-mass...
The exclusive deep inelastic electroproduction of $\psi(2S)$ and $J/\psi(1S)$ at an $ep$ centre-of-mass energy 317 GeV has been studied with the ZEUS detector HERA in kinematic range $2 < Q^2 80$ GeV$^2$, $30 W 210$ $|t| 1$ where $Q^2$ is photon virtuality, $W$ photon-proton $t$ squared four-momentum transfer proton vertex. data for 5$ GeV$^2$ were taken I running period correspond to integrated luminosity 114 pb$^{-1}$. $5 are from both II periods 468 decay modes analysed $\mu^+\mu^-$...
Production of exclusive dijets in diffractive deep inelastic $e^\pm p$ scattering has been measured with the ZEUS detector at HERA using an integrated luminosity 372 pb$^{-1}$. The measurement was performed for $γ^*-p$ centre-of-mass energies range $90 < W 250$ GeV and photon virtualities $Q^2 > 25$ GeV$^2$. Energy transverse-energy flows around jet axis are presented. cross section is presented as a function $β$ $ϕ$, where $β=x/x_{\rm I\!P}$, $x$ Bjorken variable $x_{\rm I\!P}$ proton...
Abstract The azimuthal correlation angle, $$\Delta \phi $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mi>Δ</mml:mi> <mml:mi>ϕ</mml:mi> </mml:mrow> </mml:math> , between the scattered lepton and leading jet in deep inelastic $$e^{\pm }p$$ <mml:msup> <mml:mi>e</mml:mi> <mml:mo>±</mml:mo> </mml:msup> <mml:mi>p</mml:mi> scattering at HERA has been studied using data collected with ZEUS detector a centre-of-mass energy of $$\sqrt{s} = 318 {\,\text...
Isolated photons with high transverse energy have been studied in deep inelastic ep scattering the ZEUS detector at HERA, using an integrated luminosity of 326 pb−1 range exchanged-photon virtuality 10-350 GeV2. Outgoing isolated 4 < E 15 GeV and pseudorapidity − 0.7 η γ 0.9 were measured accompanying jets having 2.5 jet 35 −1.5 ηjet 1.8, respectively. Differential cross sections are presented for following variables: fraction incoming photon momentum that is transferred to outgoing leading...