G. Ambrosi
A5008512143- Particle physics theoretical and experimental studies
- Quantum Chromodynamics and Particle Interactions
- Dark Matter and Cosmic Phenomena
- Particle Detector Development and Performance
- High-Energy Particle Collisions Research
- Astrophysics and Cosmic Phenomena
- Radiation Detection and Scintillator Technologies
- Neutrino Physics Research
- Nuclear Physics and Applications
- Solar and Space Plasma Dynamics
- Atomic and Subatomic Physics Research
- X-ray Diffraction in Crystallography
- Crystallization and Solubility Studies
- Medical Imaging Techniques and Applications
- Radiation Therapy and Dosimetry
- Gamma-ray bursts and supernovae
- Ionosphere and magnetosphere dynamics
- Cosmology and Gravitation Theories
- Geomagnetism and Paleomagnetism Studies
- Earthquake Detection and Analysis
- CCD and CMOS Imaging Sensors
- Crystallography and Radiation Phenomena
- Particle Accelerators and Free-Electron Lasers
- Radiation Effects in Electronics
- Astro and Planetary Science
Istituto Nazionale di Fisica Nucleare, Sezione di Perugia
2016-2025
European Organization for Nuclear Research
2008-2023
Czech Technical University in Prague
2023
University of Perugia
2004-2023
University of Geneva
1996-2023
Istituto Nazionale di Fisica Nucleare, Sezione di Bari
2023
Istituto Nazionale di Fisica Nucleare, Roma Tor Vergata
2017-2023
Purple Mountain Observatory
2023
University of Trento
2023
Istituto Nazionale di Fisica Nucleare
2003-2022
A precision measurement by the Alpha Magnetic Spectrometer on International Space Station of positron fraction in primary cosmic rays energy range from 0.5 to 350 GeV based $6.8\ifmmode\times\else\texttimes\fi{}{10}^{6}$ and electron events is presented. The very accurate data show that steadily increasing 10 $\ensuremath{\sim}250\text{ }\text{ }\mathrm{GeV}$, but, 20 250 GeV, slope decreases an order magnitude. spectrum shows no fine structure, ratio observable anisotropy. Together, these...
A precise measurement of the proton flux in primary cosmic rays with rigidity (momentum/charge) from 1 GV to 1.8 TV is presented based on 300 million events. Knowledge dependence important understanding origin, acceleration, and propagation rays. We present detailed variation spectral index for first time. The progressively hardens at high rigidities.Received 6 March 2015DOI:https://doi.org/10.1103/PhysRevLett.114.171103This article available under terms Creative Commons Attribution 3.0...
The Cherenkov Telescope Array, CTA, will be the major global observatory for very high energy gamma-ray astronomy over next decade and beyond. scientific potential of CTA is extremely broad: from understanding role relativistic cosmic particles to search dark matter. an explorer extreme universe, probing environments immediate neighbourhood black holes voids on largest scales. Covering a huge range in photon 20 GeV 300 TeV, improve all aspects performance with respect current instruments....
Measurements of the positron fraction in high energy cosmic rays using space-borne Alpha Magnetic Spectrometer have been extended to energies 500 GeV. The new results show that stops increasing with at around 200
Precision measurements by the Alpha Magnetic Spectrometer on International Space Station of primary cosmic-ray electron flux in range 0.5 to 700 GeV and positron 500 are presented. The each require a description beyond single power-law spectrum. Both change their behavior at ∼30 but fluxes significantly different magnitude energy dependence. Between 20 200 spectral index is harder than index. determination differing indices versus new observation provides important information origins...
Knowledge of the precise rigidity dependence helium flux is important in understanding origin, acceleration, and propagation cosmic rays. A measurement primary rays with (momentum/charge) from 1.9 GV to 3 TV based on 50 million events presented compared proton flux. The detailed variation spectral index for first time. progressively hardens at rigidities larger than 100 GV. similar that though magnitudes are different. Remarkably, ratio increases up 45 then becomes constant; above well...
A precision measurement by AMS of the antiproton flux and antiproton-to-proton ratio in primary cosmic rays absolute rigidity range from 1 to 450 GV is presented based on 3.49×10^{5} events 2.42×10^{9} proton events. The fluxes ratios charged elementary particles are also presented. In ∼60 ∼500 GV, p[over ¯], p, positron e^{+} found have nearly identical dependence electron e^{-} exhibits a different dependence. Below 60 (p[over ¯]/p), ¯]/e^{+}), (p/e^{+}) each reaches maximum. From show no...
The Alpha Magnetic Spectrometer (AMS) is a precision particle physics detector on the International Space Station (ISS) conducting unique, long-duration mission of fundamental research in space. objectives include precise studies origin dark matter, antimatter, and cosmic rays as well exploration new phenomena. Following 16-year period construction testing, precursor flight Shuttle, AMS was installed ISS May 19, 2011. In this report we present results based 120 billion charged ray events up...
Knowledge of the rigidity dependence boron to carbon flux ratio (B/C) is important in understanding propagation cosmic rays. The precise measurement B/C from 1.9 GV 2.6 TV, based on 2.3 million and 8.3 nuclei collected by AMS during first 5 years operation, presented. detailed variation with spectral index reported for time. does not show any significant structures contrast many ray models that require such at high rigidities. Remarkably, above 65 GV, well described a single power law R^{Δ}...
A measurement of the cosmic ray positron fraction e+/(e++e−) in energy range 1–30 GeV is presented. The based on data taken by AMS-01 experiment during its 10 day Space Shuttle flight June 1998. proton background suppression order 106 reached identifying converted bremsstrahlung photons emitted from positrons.
We report the observation of new properties primary cosmic rays He, C, and O measured in rigidity (momentum/charge) range 2 GV to 3 TV with 90×10^{6} helium, 8.4×10^{6} carbon, 7.0×10^{6} oxygen nuclei collected by Alpha Magnetic Spectrometer (AMS) during first five years operation. Above 60 GV, these three spectra have identical dependence. They all deviate from a single power law above 200 harden an way.
We present a measurement of the cosmic ray (e^{+}+e^{-}) flux in range 0.5 GeV to 1 TeV based on analysis 10.6 million events collected by AMS. The statistics and resolution AMS provide precision flux. is smooth reveals new distinct information. Above 30.2 GeV, can be described single power law with spectral index γ=-3.170±0.008(stat+syst)±0.008(energy scale).
Precision measurements of cosmic ray positrons are presented up to 1 TeV based on 1.9 million collected by the Alpha Magnetic Spectrometer International Space Station. The positron flux exhibits complex energy dependence. Its distinctive properties (a) a significant excess starting from 25.2±1.8 GeV compared lower-energy, power-law trend, (b) sharp dropoff above 284+91−64 GeV, (c) in entire range is well described sum term associated with produced collision rays, which dominates at low...
We report on the observation of new properties secondary cosmic rays Li, Be, and B measured in rigidity (momentum per unit charge) range 1.9 GV to 3.3 TV with a total 5.4×10^{6} nuclei collected by AMS during first five years operation aboard International Space Station. The Li fluxes have an identical dependence above 7 all three 30 Li/Be flux ratio 2.0±0.1. deviate from single power law 200 way. This behavior has also been observed measurement primary He, C, O but dependences are...
Precision results on cosmic-ray electrons are presented in the energy range from 0.5 GeV to 1.4 TeV based $28.1\ifmmode\times\else\texttimes\fi{}{10}^{6}$ collected by Alpha Magnetic Spectrometer International Space Station. In entire electron and positron spectra have distinctly different magnitudes dependences. The flux exhibits a significant excess starting $42.{1}_{\ensuremath{-}5.2}^{+5.4}\text{ }\text{ }\mathrm{GeV}$ compared lower trends, but nature of this is above...
We provide an updated assessment of the power Cherenkov Telescope Array (CTA) to search for thermally produced dark matter at TeV scale, via associated gamma-ray signal from pair-annihilating particles in region around Galactic centre. find that CTA will open a new window discovery potential, significantly extending range robustly testable models given standard cuspy profile density distribution. Importantly, even cored profile, projected sensitivity be sufficient probe various...
We present results over an 11-year Solar cycle of cosmic antiprotons based on <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mn>1.1</a:mn><a:mo>×</a:mo><a:msup><a:mn>10</a:mn><a:mn>6</a:mn></a:msup></a:math> events in the rigidity range from 1.00 to 41.9 GV. The <c:math xmlns:c="http://www.w3.org/1998/Math/MathML" display="inline"><c:mover accent="true"><c:mi>p</c:mi><c:mo stretchy="false">¯</c:mo></c:mover></c:math> fluxes exhibit distinct properties. magnitude...
The design and construction of the silicon strip microvertex detector (SMD) L3 experiment at LEP are described. We present sensors, readout electronics, data acquisition system, mechanical assembly support, displacement monitoring systems radiation system recently installed double-sided, double-layered SMD. This utilizes novel sophisticated techniques for its readout.