Yu. G. Sobolev
A5021176789- Nuclear physics research studies
- Quantum Chromodynamics and Particle Interactions
- Nuclear Physics and Applications
- High-Energy Particle Collisions Research
- Particle physics theoretical and experimental studies
- Astronomical and nuclear sciences
- Nuclear reactor physics and engineering
- Atomic and Molecular Physics
- Radiation Detection and Scintillator Technologies
- Particle Detector Development and Performance
- Superconducting Materials and Applications
- Advanced Chemical Physics Studies
- Advanced NMR Techniques and Applications
- Quantum, superfluid, helium dynamics
- X-ray Spectroscopy and Fluorescence Analysis
- Neutrino Physics Research
- Astro and Planetary Science
- Radioactive Decay and Measurement Techniques
- Particle accelerators and beam dynamics
- Dark Matter and Cosmic Phenomena
- Mass Spectrometry Techniques and Applications
- Medical Imaging Techniques and Applications
- Radiopharmaceutical Chemistry and Applications
- Inorganic Fluorides and Related Compounds
- Rare-earth and actinide compounds
Joint Institute for Nuclear Research
2016-2025
Czech Academy of Sciences, Nuclear Physics Institute
2013-2023
Dubna State University
1995-2022
Moscow Engineering Physics Institute
2021
Laboratoire de Physique des 2 Infinis Irène Joliot-Curie
2021
Institut National de Physique Nucléaire et de Physique des Particules
2021
Université Paris-Saclay
2021
Centre National de la Recherche Scientifique
2021
University of Warsaw
2021
Frederick University
2021
In-beam γ-ray spectroscopy using fragmentation reactions of both stable and radioactive beams has been performed in order to study the structure excited states neutron-rich oxygen isotopes with masses ranging from A=20 24. For produced fragments, energies, intensities, γ−γ coincidences have measured. Based on this information new level schemes are proposed for O21,22 up neutron separation energy. The nonobservation any γ-decay branch O23 O24 suggests that their lie above decay thresholds....
We present phase space distributions and multiplicities of K+, K−, ϕ mesons produced in Ar+KCl reactions at a kinetic beam energy 1.756 GeV/nucleon measured with the HADES spectrometer. The inverse slope parameters yields kaons supplement systematics previous measurements. percentage K− coming from decay is found to be 18±7%.6 MoreReceived 9 March 2009DOI:https://doi.org/10.1103/PhysRevC.80.025209©2009 American Physical Society
We present transverse momentum spectra, rapidity distribution and multiplicity of $ \Lambda$ -hyperons measured with the HADES spectrometer in reaction Ar(1.76AGeV) + KCl . The yield \Xi^{{-}}_{}$ is calculated from our previously reported /( \Sigma^{{0}}_{}$ ) ratio compared to other strange particle multiplicities. Employing a strangeness balance equation multiplicities yet unmeasured \Sigma^{{\pm}}_{}$ can be estimated. Finally statistical hadronization model used fit yields \pi^{-}_{}$ ,...
We report first results on a deep subthreshold production of the doubly strange hyperon Xi;{-} in heavy-ion reaction. At beam energy 1.76A GeV reaction Ar + KCl was studied with High Acceptance Di-Electron Spectrometer at SIS18/GSI. A high-statistics and high-purity Lambda sample collected, allowing for investigation decay channel --> Lambdapi;{-}. The deduced Xi;{-}/(Lambda Sigma;{0}) ratio (5.6 +/- 1.2_{-1.7};{+1.8}) x 10;{-3} is significantly larger than available model predictions.
We present a search for the e+e− decay of hypothetical dark photon, also named U vector boson, in inclusive dielectron spectra measured by HADES p(3.5 GeV) + p, Nb reactions, as well Ar (1.756 GeV/u) KCl reaction. An upper limit on kinetic mixing parameter squared ϵ2 at 90% CL has been obtained mass range MU=0.02–0.55 GeV/c2 and is compared with world data set. For masses 0.03–0.1 GeV/c2, lowered respect to previous results, allowing now exclude large part region favored muon g−2 anomaly....
Employing the Bonn–Gatchina partial wave analysis framework (PWA), we have analyzed HADES data of reaction p(3.5GeV)+p→pK+Λ. This might contain information about kaonic cluster "ppK−" (with quantum numbers JP=0− and total isospin I=1/2) via its decay into pΛ. Due to interference effects in our coherent description data, a hypothetical K‾NN (or, specifically "ppK−") signal need not necessarily show up as pronounced feature (e.g. peak) an invariant mass spectrum like Our PWA includes variety...
We present the transverse momentum spectra and rapidity distributions of ${\ensuremath{\pi}}^{\ensuremath{-}}$ ${\mathrm{K}}_{S}^{0}$ in Ar $+$ KCl reactions at a beam kinetic energy $1.756$ $A$ GeV measured with High Acceptance Di-Electron Spectrometer (HADES). The reconstructed sample is characterized by good event statistics for wide range rapidity. compare experimental to predictions Isospin Quantum Molecular Dynamics (IQMD) model. model calculations show that low momenta constitute...
We report measurements of electron pair production in elementary p+p and d+p reactions at 1.25 GeV/u with the HADES spectrometer. For first time, pairs were reconstructed for n+p by detecting proton spectator from deuteron breakup. find that yield invariant mass Me+e- > 0.15 GeV/c2 is about an order magnitude larger as compared to p+p. A comparison model calculations demonstrates mechanism not sufficiently described yet. The spectra measured C+C are compatible a superposition collisions,...
We present results on dielectron production in ${}^{40}\mathrm{Ar}+\mathrm{KCl}$ collisions at 1.76$A$ GeV. For the first time $\ensuremath{\omega}$ mesons could be reconstructed a heavy-ion reaction bombarding energy which is well below threshold free nucleon-nucleon collisions. The multiplicity has been extracted and compared to yields of other particles, particular $\ensuremath{\varphi}$ meson. At intermediate ${e}^{+}{e}^{\ensuremath{-}}$ invariant masses, we find strong enhancement pair...
We present an analysis of the Lambda(1405) resonance produced in reaction p+p->Sigma^{pm}+pi^{mp}+K+p at 3.5 GeV kinetic beam energy measured with HADES GSI. The two charged decay channels -> Sigma^{\pm}+pi^{\mp} have been reconstructed for first time p+p collisions. efficiency and acceptance-corrected spectral shapes show a peak position clearly below 1400 MeV/c^2. find total production cross section sigma_{Lambda(1405)}=9.2 +- 0.9 0.7 +3.3-1.0 mub. its polar angle distribution suggests...
We present the inclusive invariant-mass, transverse momentum and rapidity distributions of dielectrons (e$^{+}$e$^{-}$ pairs) in p+p interactions at 3.5 GeV beam kinetic energy. In vector-meson mass region, a distinct peak corresponding to direct $\omega$ decays is reconstructed with 2% resolution. The data compared predictions from three model calculations. Due large acceptance HADES apparatus for $e^{+}e^{-}$ invariant masses above 0.2 GeV/$c^{2}$ pair momenta p$_{t}$ $ <$ 1 GeV/$c$,...
Abstract High-precision measurements of flow coefficients $$v_{n}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mi>v</mml:mi> <mml:mi>n</mml:mi> </mml:msub> </mml:math> ( $$n = 1 - 4$$ <mml:mrow> <mml:mo>=</mml:mo> <mml:mn>1</mml:mn> <mml:mo>-</mml:mo> <mml:mn>4</mml:mn> </mml:mrow> ) for protons, deuterons and tritons relative to the first-order spectator plane have been performed in Au+Au collisions at $$\sqrt{s_{_{{\text {NN}}}}}= 2.4$$ <mml:msqrt>...
We present results of an exclusive measurement the first-excited state $\ensuremath{\Sigma}$ hyperon, $\ensuremath{\Sigma}{(1385)}^{+}$, produced in $p+p\ensuremath{\rightarrow}{\ensuremath{\Sigma}}^{+}+{K}^{+}+n$ at $3.5\phantom{\rule{0.28em}{0ex}}\mathrm{GeV}$ beam energy. The extracted data allow detailed study invariant mass distribution $\ensuremath{\Sigma}{(1385)}^{+}$. is well described by a relativistic Breit-Wigner function with maximum...
We present data on charged kaons (K+-) and {\phi} mesons in Au(1.23A GeV)+Au collisions. It is the first simultaneous measurement of K central heavy-ion collisions below a kinetic beam energy 10A GeV. The {\phi}/K- multiplicity ratio found to be surprisingly high with value 0.52 +- 0.16 shows no dependence centrality collision. Consequently, different slopes K+ K- transverse-mass spectra can explained solely by feed- down, which substantially softens mesons. Hence, contrast commonly adapted...
We present data on dielectron emission in proton induced reactions a Nb target at 3.5 GeV kinetic beam energy measured with HADES installed GSI. The represent the first high statistics measurement of proton-induced radiation from cold nuclear matter kinematic regime, where strong medium effects are expected. Combined good mass resolution 2%, it is sensitive to changes spectral functions vector mesons, as predicted by models for hadrons rest or small relative momenta. Comparing e+e invariant...
We report on baryon resonance production and decay in proton-proton collisions at a kinetic energy of 3.5 GeV based data measured with HADES. The exclusive channels $ pp \rightarrow np\pi^{+}$ pp\rightarrow pp\pi^{0}$ as well ppe^{+}e^{-}$ are studied simultaneously for the first time. invariant masses angular distributions pion-nucleon systems were compared to simulations model ansatz assuming saturation pion by an incoherent sum baryonic resonances (R < 2 GeV/c2. A very good description...
We present first data on sub-threshold production of K0 s mesons and Λ hyperons in Au+Au collisions at $\sqrt{s_{NN}}$ = 2.4 GeV. observe an universal scaling hadrons containing strangeness, independent their corresponding thresholds. Comparing the yields, scaling, shapes rapidity pt spectra to state-of-the-art transport model (UrQMD, HSD, IQMD) predictions, we find that none latter can simultaneously describe all observables with reasonable \c{hi}2 values.