A5014381163- Quantum Chromodynamics and Particle Interactions
- Particle physics theoretical and experimental studies
- High-Energy Particle Collisions Research
- Atomic and Molecular Physics
- Atomic and Subatomic Physics Research
- Muon and positron interactions and applications
- Particle Detector Development and Performance
- Radiation Detection and Scintillator Technologies
- Nuclear physics research studies
- Radioactive Decay and Measurement Techniques
- Nuclear Physics and Applications
- High-pressure geophysics and materials
- Dark Matter and Cosmic Phenomena
- Quantum, superfluid, helium dynamics
- Quantum Mechanics and Applications
- X-ray Spectroscopy and Fluorescence Analysis
- Ionosphere and magnetosphere dynamics
- Cold Atom Physics and Bose-Einstein Condensates
- Medical Imaging Techniques and Applications
- Superconducting Materials and Applications
- Advanced Chemical Physics Studies
- Neutrino Physics Research
- Noncommutative and Quantum Gravity Theories
- Scientific Research and Discoveries
- Magnetic confinement fusion research
Stefan Meyer Institute for Subatomic Physics
2015-2024
University of Vienna
1980-2024
Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Frascati
2011-2024
Istituto Nazionale di Fisica Nucleare
2018-2024
Technical University of Munich
1993-2024
TU Wien
1982-2023
Austrian Academy of Sciences
2013-2022
Tokyo Institute of Technology
2022
Enrico Fermi Center for Study and Research
2021-2022
Excellence Cluster Universe
2021-2022
Stannic oxide in its pure form is an n‐type wide‐bandgap semiconductor. Its electrical conduction results from the existence of point defects (native and foreign atoms) which act as donors or acceptors. Some unique properties make material useful for many applications. Therefore, increasing attention being paid to studies on this oxide, especially methods preparation, optical properties. The purpose work provide a general up‐to‐date review investigations carried out help identify important...
Stannic oxide in its pure form is an n‐type wide‐bandgap semiconductor. Its electrical conduction results from the existence of point defects (native and foreign atoms) which act as donors or acceptors. Some unique properties make material useful for many applications. Therefore, increasing attention being paid to studies on this oxide, especially methods preparation, optical properties. The purpose series provide a general up‐to‐date review investigations carried out help identify important...
The $\bar{K}N$ system at threshold is a sensitive testing ground for low energy QCD, especially the explicit chiral symmetry breaking. Therefore, we have measured $K$-series x rays of kaonic hydrogen atoms DA$\Phi$NE electron-positron collider Laboratori Nazionali di Frascati, and determined most precise values strong-interaction energy-level shift width $1s$ atomic state. As x-ray detectors, used large-area silicon drift detectors having excellent timing resolution, which were developed...
The DEAR (DAPhiNE exotic atom research) experiment measured the energy of x rays emitted in transitions to ground state kaonic hydrogen. values for shift epsilon and width Gamma 1s due K(-)p strong interaction are epsilon(1s)=-193 +/- 37 (stat) 6 (syst) eV Gamma(1s)=249 111 30 eV, most precise yet obtained. pattern hydrogen K-series lines, K(alpha), K(beta), K(gamma), was disentangled first time.
The nucleation, early growth, and structure of Ni‐P on activated dielectric substrates were studied. treatment was found to provide small catalytic sites the substrate, serving as nuclei for growth. average diameter estimated be less than 10Aå. microscopic time rate growth constant isotropic. resulting deposit in stages consists circular islands. surface density σ islands affected by activation. In later merged form a continuous film. critical film thickness at which continuity is attained...
Muon-catalyzed deuterium-tritium fusion was investigated within a wide range of mixtures in liquid and gas (23--35 K) by detection neutrons. Our improved analysis includes hyperfine effects allows clear separation intrinsic dt sticking ${\ensuremath{\omega}}_{s}$ from kinetic effects. Strongly density-dependent cycle rates with values up to 1.45\ifmmode\times\else\texttimes\fi{}${10}^{8}$ ${\mathrm{s}}^{\mathrm{\ensuremath{-}}1}$, yields 113 fusions per muon,...
In this part, the simplest optical theory of aggregated metal systems, due to Maxwell-Garnett, is analyzed. The complex dielectric constant system, and that constituent aggregates, are represented as transformations. functions show single double poles in certain regions physical interest, indicating resonance behavior. These features explored for free-electron metals, an "conduction resonance" system discovered. frequency magnitude conductivity calculated, along with plasma bulk electron...
Kaonic atoms are exotic atomic systems where an electron is replaced by a negatively charged kaon which also experiences the strong interaction with nucleus. Precision spectroscopy of kaonic represents excellent tool to study particles strangeness. This work reviews progress and prospects in modern era atom experiments, discusses constraints on low-energy theories strangeness sector.
We report the measurement of K− absorption processes in Σ0p final state and first exclusive two nucleon (2NA) with KLOE detector. The 2NA process without further interactions is found to be 9% sum all other contributing processes, including on three more nucleons or followed by residual nucleons. also determine possible contribution ppK− bound state. yield ppK−/Kstop− (0.044±0.009stat−0.005+0.004syst)⋅10−2 but its statistical significance based an F-test only 1σ.
We observed a distinct peak in the Λp invariant mass spectrum of He3(K−,Λp)n, well below mK+2mp, i.e., threshold K− to be bound two protons. By selecting relatively large momentum-transfer region q=350∼650 MeV/c, one can kinematically separate from quasi-free process, K‾N→K‾N followed by non-resonant absorption spectator-nucleons K‾NN→ΛN. found that simplest fit gives us Breit–Wigner pole position at BKpp=47±3(stat.)−6+3(sys.) MeV having width ΓKpp=115±7(stat.)−20+10(sys.) MeV, and S-wave...
We have measured the Balmer-series x-rays of kaonic $^4$He atoms using novel large-area silicon drift x-ray detectors in order to study low-energy $\bar{K}$-nucleus strong interaction. The energy $3d \to 2p$ transition was determined be 6467 $\pm$ 3 (stat) 2 (syst) eV. resulting strong-interaction energy-level shift is agreement with theoretical calculations, thus eliminating a long-standing discrepancy between theory and experiment.
A model where a Dirac fermion is coupled to background dilaton field considered study s-wave scattering of by back ground black hole. It found that an uncomfortable situation towards information loss scenario arises when one loop correction gets involved during bosonization.
High rates for mesomolecular processes were found in a study of neutron spectra from muon-catalyzed $\mathrm{dt}$ fusion low-density D/T mixtures. An interpretation is given terms reaction-kinetics model which includes hyperfine effects. The components the $d\ensuremath{\mu}t$ formation rates, first separated this experiment, are large 30 to 300 K. unexpected temperature dependence transition rate between $\ensuremath{\mu}t$ states found.
Abstract The hadronic width of the ground state pionic hydrogen has been redetermined by X-ray spectroscopy to be $$\varGamma ^{\pi \mathrm {H}}_{1s}=(856\,\pm \,16_\mathrm{stat}\,\pm \,22_\mathrm{sys})$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:msubsup> <mml:mi>Γ</mml:mi> <mml:mn>1</mml:mn> <mml:mi>s</mml:mi> </mml:mrow> <mml:mi>π</mml:mi> <mml:mi>H</mml:mi> </mml:msubsup> <mml:mo>=</mml:mo> <mml:mo>(</mml:mo> <mml:mn>856</mml:mn> <mml:mspace />...
A large area silicon drift detectors (SDDs) system and its readout electronics have been developed by the SIDDHARTA-2 Collaboration, aiming to perform high-precision light kaonic atoms x-ray spectroscopy for investigation of strong interaction in low-energy QCD regime. To these measurements, a linear energy response good resolution are mandatory requirements system, be preserved along whole DAQ (analog digital) chain; such task is made even harder experimental environment particles...
Abstract The current work presents the optimization of large area silicon drift detectors developed by SIDDHARTA-2 collaboration for high precision x-ray measurements light exotic atom transitions. Two different radiation sources were employed in study: an tube, investigating energy resolution and charge collection efficiency device range 4000 eV–13 000 eV, a β − 90 Sr radioactive source measuring timing response, thus qualifying parameters inside semiconductor. study reports spectroscopic...
This paper reports an experimental investigation of muon-catalyzed fusion in pure deuterium by detection dd neutrons. Target temperatures 25.5--150 K and gas densities 2% 5% liquid-hydrogen density were used. The rates \ensuremath{\lambda}\ifmmode \tilde{}\else \~{}\fi{}F for dd\ensuremath{\mu} formation from both hyperfine states d\ensuremath{\mu} atoms as well the transition \~{}\fi{}FF\ensuremath{'} separated a kinetic analysis observed time spectra. measurement temperature dependence all...
In previous publications we reported on the optical properties of aggregated metal systems, where particles were assumed to be free-electron type with damping, and they dispersed in a dielectric medium varying index refraction. The main results shift bulk surface plasma frequencies aggregation density appearance an extra resonance, called conduction resonance (OCR), low-energy side frequency. OCR was shown transverse collective mode free electrons aggregates which could excited by incident...