A5107997147- Particle physics theoretical and experimental studies
- High-Energy Particle Collisions Research
- Particle Detector Development and Performance
- Quantum Chromodynamics and Particle Interactions
- Dark Matter and Cosmic Phenomena
- Astrophysics and Cosmic Phenomena
- Neutrino Physics Research
- Radiation Detection and Scintillator Technologies
- Radio Astronomy Observations and Technology
- Cosmology and Gravitation Theories
- Computational Physics and Python Applications
- Medical Imaging Techniques and Applications
- Atomic and Subatomic Physics Research
- Atmospheric Ozone and Climate
- Black Holes and Theoretical Physics
- Gamma-ray bursts and supernovae
- Nuclear physics research studies
- CCD and CMOS Imaging Sensors
- Nuclear Physics and Applications
- Pulsars and Gravitational Waves Research
- Ionosphere and magnetosphere dynamics
- Muon and positron interactions and applications
- Solar and Space Plasma Dynamics
- Distributed and Parallel Computing Systems
- Radiation Therapy and Dosimetry
LIP - Laboratory of Instrumentation and Experimental Particle Physics
2016-2025
University of Lisbon
2016-2025
University of Coimbra
2015-2024
Airbus (France)
2024
Laboratoire d'Analyse et d'Architecture des Systèmes
2024
Université de Cepromad
2024
George Washington University
2024
Universidade Estadual de Campinas (UNICAMP)
2017-2023
The University of Adelaide
2013-2023
Institute of Astronomy and Space Physics
2016-2023
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 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...
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...
The global polarization of {\Lambda} hyperons along the total orbital angular momentum a relativistic heavy-ion collision is presented based on high statistics data samples collected in Au+Au collisions at \sqrt{s_{NN}} = 2.4 GeV and Ag+Ag 2.55 with High-Acceptance Di-Electron Spectrometer (HADES) GSI, Darmstadt. This first measurement below strangeness production threshold nucleon-nucleon collisions. Results are reported as function centrality well hyperon transverse (p_T) rapidity (y_{CM})...
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>...
In this work we explore readout architectures for the simultaneous high-resolution timing and bidimensional tracking of charged particles with Resistive Plate Chambers (TOF-tracker) accurate detection gamma rays PET imaging. On 625 $cm^2$ active area obtained a time resolution 61 ps $\sigma$ position below 150 $\mu$m from cosmic rays. An intrinsic precision 0.49 mm FWHM was determined localization small $\beta^+$ source via its annihilation radiation.
The phase-out of Hydrofluorocarbons (HFCs), due to their high Global Warming Potential (GWP), affecting the main gas used in Resistive Plate Chambers (RPCs), tetrafluorethane C2H2F4, has created operational difficulties on existing systems and imposes strict restrictions its use new systems. A possible solution problem is substitution this by others with a much lower GWP. This approach attracted attention an important part community recent years. But there could be another possibility, which...
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...