P. Levi Sandri
- Particle physics theoretical and experimental studies
- Quantum Chromodynamics and Particle Interactions
- High-Energy Particle Collisions Research
- Nuclear Physics and Applications
- Atomic and Subatomic Physics Research
- Nuclear physics research studies
- Particle Detector Development and Performance
- Particle Accelerators and Free-Electron Lasers
- Dark Matter and Cosmic Phenomena
- Radiation Detection and Scintillator Technologies
- Superconducting Materials and Applications
- X-ray Spectroscopy and Fluorescence Analysis
- Atomic and Molecular Physics
- Medical Imaging Techniques and Applications
- Nuclear reactor physics and engineering
- Particle accelerators and beam dynamics
- Ionosphere and magnetosphere dynamics
- Cold Atom Physics and Bose-Einstein Condensates
- High-pressure geophysics and materials
- Gamma-ray bursts and supernovae
- Geophysics and Gravity Measurements
- Quantum, superfluid, helium dynamics
- Quantum optics and atomic interactions
- Scientific Computing and Data Management
- Advanced X-ray Imaging Techniques
Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Frascati
2015-2024
Russian Academy of Sciences
2022
Institute for Nuclear Research
2022
RIKEN
2010-2021
Istituto Nazionale di Fisica Nucleare
1993-2021
Jagiellonian University
2015-2021
Institute of Physics
2015-2021
Politecnico di Milano
2010-2021
Stefan Meyer Institute for Subatomic Physics
2010-2021
Horia Hulubei National Institute for R and D in Physics and Nuclear Engineering
2010-2021
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...
A new experiment is described to detect a permanent electric dipole moment of the proton with sensitivity $10^{-29}e\cdot$cm by using polarized "magic" momentum $0.7$~GeV/c protons in an all-electric storage ring. Systematic errors relevant are discussed and techniques address them presented. The measurement sensitive physics beyond Standard Model at scale 3000~TeV.
We present new $\ensuremath{\Sigma}$ beam asymmetry data for $\ensuremath{\eta}$ meson photoproduction on the proton, using a novel tagged, laser backscattered, linearly polarized photon up to 1.1 GeV. The show large, positive asymmetries, at all incident energies. In addition ${S}_{11}(1535)$ and ${D}_{13}(1520)$ resonances necessary reproduce cross sections, ${P}_{13}(1720)$ ${D}_{15}(1675)$ ``four stars'' contribute observable, but cannot strong forward asymmetries measured energies...
The total photoabsorption cross section for $^{7}\mathrm{Li}$, C, Al, Cu, Sn, Pb has been measured in the energy range 300--1200 MeV at Frascati with jet-target tagged photon beam. A 4\ensuremath{\pi} NaI crystal detector and a lead-glass shower counter were used, respectively, to measure hadronic events reject electromagnetic background. Data above 600 clearly indicate broadening of higher nucleon resonance peaks nuclei reduction absolute value per respect free-nucleon case. This large...
The goal of the DIRAC experiment at CERN (PS212) is to measure $\pi^+\pi^-$ atom lifetime with 10% precision. Such a measurement would yield precision 5% on value $S$-wave $\pi\pi$ scattering lengths combination $|a_0-a_2|$. Based part collected data we present first result lifetime, $\tau=[2.91 ^{+0.49}_{-0.62}]\times 10^{-15}$ s, and discuss major systematic errors. This corresponds $|a_0-a_2|=0.264 ^{+0.033}_{-0.020} m_{\pi}^{-1}$.
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.
The BGOOD photoproduction experiment accesses forward meson angles and low momentum exchange kinematics in the $uds$ sector, which may be sensitive to molecular-like hadron structure. Our results strangeness sector suggest a dominant role of meson-baryon dynamics. This includes structures $K^0\Sigma^0$, $K^+\Sigma^0$ $K^+\Sigma^0(1385)$ residing at $\Sigma^{(*)}K^{(*)}$ thresholds have an equivalence $P_C$ states $\Sigma_C^{(*)}\bar D^{(*)}$ thresholds. In non-strange baryon-baryon...
The double π0 photoproduction off the proton has been measured in beam energy range of 0.65–1.5 GeV. total and differential cross sections Σ asymmetry were extracted. section for first time third resonance region nucleon shows a prominent peak. interpretation these results by two independent theoretical models infers mostly selective excitation P11- D13-nucleon resonances.Received 17 January 2003DOI:https://doi.org/10.1103/PhysRevLett.90.222001©2003 American Physical Society
The possibility of anisotropies in the speed light relative to limiting electrons is considered. absence sidereal variations energy Compton-edge photons at European Synchrotron Radiation Facility's GRAAL facility constrains such representing first nonthreshold collision-kinematics study Lorentz violation. When interpreted within minimal standard-model extension, this result yields two-sided limit 1.6×10−14 95% confidence level on a combination parity-violating photon and electron...
The analysis of the γp→ηπ0p reaction has been performed using data from GRAAL experiment. total and differential cross sections beam asymmetry have obtained threshold up to 1.5 GeV energy. two resonances S11(1535) Δ(1700) are expected be excited in intermediate states this reaction. results used test predictions based on assumption that both dynamically generated meson-baryon interaction provided by chiral Lagrangians. term involving excitation, followed decay into ηΔ(1232), is found...
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...
The differential cross section for the reaction p(γ,ηp) has been measured from threshold to 1100 MeV photon laboratory energy. For first time, region of S11(1535) resonance is fully covered in a photoproduction experiment and will allow precise extraction its parameters at point. These high precision data together with already beam asymmetry provide stringent constraints on new couplings baryon resonances η meson.
The DIRAC experiment at CERN has achieved a sizeable production of $\pi^+\pi^-$ atoms and significantly improved the precision on its lifetime determination. From sample 21227 atomic pairs, 4% measurement S-wave $\pi\pi$ scattering length difference $|a_0-a_2| = (.0.2533^{+0.0080}_{-0.0078}|_\mathrm{stat}.{}^{+0.0078}_{-0.0073}|_\mathrm{syst})M_{\pi^+}^{-1}$ been attained, providing an important test Chiral Perturbation Theory.
The kaonic (3)He and (4)He X-rays emitted in the [Formula: see text] transitions were measured SIDDHARTA experiment. widths of 2p states determined to be text], respectively. Both results are consistent with theoretical predictions. width is much smaller than value by experiments performed 70's 80's, while was for first time.
The hyperspeed growth of data center power demand starts with the high consumption required by current and upcoming generations digital application-specific integrated circuits (ASICs)-central processing unit (CPU), double rate memories (DDR) networking ASICs-in addition to exploding use high-power graphics units (GPUs) for artificial intelligence machine-learning functions. Hyperscale centers will also increase in number, from 259 at end 2015 485 2020. They represent 47% all installed...