Y. Parpottas
A5039195977- High-Energy Particle Collisions Research
- Quantum Chromodynamics and Particle Interactions
- Particle physics theoretical and experimental studies
- Nuclear physics research studies
- Medical Imaging Techniques and Applications
- Advanced MRI Techniques and Applications
- Atomic and Molecular Physics
- Advanced X-ray and CT Imaging
- Particle Detector Development and Performance
- Cardiac Imaging and Diagnostics
- Hemoglobinopathies and Related Disorders
- Iron Metabolism and Disorders
- Nuclear Physics and Applications
- Radiation Dose and Imaging
- Radioactivity and Radon Measurements
- Particle accelerators and beam dynamics
- Trace Elements in Health
- X-ray Spectroscopy and Fluorescence Analysis
- Atomic and Subatomic Physics Research
- Nuclear reactor physics and engineering
- Geochemistry and Geologic Mapping
- Electron and X-Ray Spectroscopy Techniques
- Advanced Chemical Physics Studies
- Astronomical and nuclear sciences
- Radiomics and Machine Learning in Medical Imaging
Frederick University
2015-2025
University of Cyprus
2013-2024
Technical University of Darmstadt
2013-2022
Helmholtz-Zentrum Dresden-Rossendorf
2019-2021
Slovak Academy of Sciences
2018-2019
Institute of Physics of the Slovak Academy of Sciences
2018-2019
University of Turin
2019
Jagiellonian University
2012-2017
Institute of Physics
2012-2017
GSI Helmholtz Centre for Heavy Ion Research
2014
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 an analysis of proton number fluctuations in $\sqrt{s_{NN}}$ = 2.4 GeV Au+Au collisions measured with the High-Acceptance DiElectron Spectrometer (HADES) at GSI. With help extensive detector simulations done IQMD transport model events including nuclear clusters, various nuisance effects influencing observed cumulants have been investigated. Acceptance and efficiency corrections applied as a function fine grained rapidity transverse momentum bins, well considering local track...
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 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...
Flow coefficients $v_{n}$ of the orders $n = 1 - 6$ are measured with High-Acceptance DiElectron Spectrometer (HADES) at GSI for protons, deuterons and tritons as a function centrality, transverse momentum rapidity in Au+Au collisions $\sqrt{s_{NN}} 2.4$ GeV. Combining information from flow all allows to construct first time, collision energies few GeV, multi-differential picture angular emission pattern these particles. It reflects complicated interplay between effect central fireball...
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>...
Differentiated thyroid cancer treatment typically involves the surgical removal of whole or largest part gland. Diagnostic procedures are useful both before and after to determine need for radioiodine ablation, re-stage disease, monitor disease progression, evaluate efficacy. SPECT/CT imaging can be utilized identify small, distant iodine-avid metastatic lesions assess their uptake volume above purposes as well performing lesion-based dosimetry when indicated. The objective this study was...
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.
We present the analysis of inclusive ${K}^{0}$ production in $p+p$ and $p+\mathrm{Nb}$ collisions measured with HADES detector (GSI Helmholtzzentrum for Heavy-Ion Research, Darmstadt) at a beam kinetic energy 3.5 GeV. Data are compared to Giessen Boltzmann-Uehling-Uhlenbeck (GiBUU) transport model. The data suggest presence repulsive momentum-dependent kaon potential as predicted by chiral perturbation theory (ChPT). For rest normal nuclear density, ChPT amounts $\ensuremath{\approx}35$ MeV....