V. Formato
A5047829738- Dark Matter and Cosmic Phenomena
- Astrophysics and Cosmic Phenomena
- Solar and Space Plasma Dynamics
- Particle Detector Development and Performance
- Ionosphere and magnetosphere dynamics
- Astro and Planetary Science
- Particle physics theoretical and experimental studies
- Atomic and Subatomic Physics Research
- Neutrino Physics Research
- Radiation Therapy and Dosimetry
- Geomagnetism and Paleomagnetism Studies
- Atmospheric Ozone and Climate
- Radiation Detection and Scintillator Technologies
- Gamma-ray bursts and supernovae
- Nuclear Physics and Applications
- Advanced Data Storage Technologies
- Distributed and Parallel Computing Systems
- Scientific Computing and Data Management
- Cosmology and Gravitation Theories
- Earthquake Detection and Analysis
- Quantum, superfluid, helium dynamics
- Cloud Computing and Resource Management
- Muon and positron interactions and applications
- Radioactivity and Radon Measurements
- High-Energy Particle Collisions Research
Istituto Nazionale di Fisica Nucleare, Roma Tor Vergata
2013-2025
University of Trieste
2011-2024
Istituto Nazionale di Fisica Nucleare, Sezione di Trieste
2011-2024
Istituto Nazionale di Fisica Nucleare, Sezione di Roma I
2024
Istituto Nazionale di Fisica Nucleare, Sezione di Perugia
2015-2023
University of Perugia
2023
Istituto Nazionale di Fisica Nucleare, Sezione di Bari
2023
Purple Mountain Observatory
2023
Istituto Nazionale di Fisica Nucleare
2013-2021
University of Rome Tor Vergata
2011-2021
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}...
Precision measurements of the positron component in cosmic radiation provide important information about propagation rays and nature particle sources our Galaxy. The satellite-borne experiment PAMELA has been used to make a new measurement cosmic-ray flux fraction that extends previously published up 300 GeV kinetic energy. combined energy spectrum unique tool constrain interpretation models. During recent solar minimum activity period from July 2006 December 2009 approximately 24500...
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.
The energy spectra of galactic cosmic rays carry fundamental information regarding their origin and propagation. These spectra, when measured near Earth, are significantly affected by the solar magnetic field. A comprehensive description radiation must therefore include transport modulation inside heliosphere. During end last decade Sun underwent a peculiarly long quiet phase well suited to study processes. In this paper we present proton from July 2006 December 2009 PAMELA. large collected...
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 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...
Precision measurements of the electron component in cosmic radiation provide important information about origin and propagation rays Galaxy not accessible from study cosmic-ray nuclear components due to their differing diffusion energy-loss processes. However, when measured near Earth, effects modulation galactic heliosphere, particularly significant for energies up at least 30 GeV, must be properly taken into account. In this paper (e^-) spectra by PAMELA down 70 MeV July 2006 December 2009...
We present the precision measurement from May 2011 to 2017 (79 Bartels rotations) of proton fluxes at rigidities 1 60 GV and helium 1.9 based on a total 1×10^{9} events collected with Alpha Magnetic Spectrometer aboard International Space Station. This is in solar cycle 24, which has maximum April 2014. observed that, below 40 GV, flux show nearly identical fine structures both time relative amplitude. The amplitudes decrease increasing rigidity vanish above GV. are reduced during period,...
The propagation of cosmic rays inside our galaxy plays a fundamental role in shaping their injection spectra into those observed at Earth. One the best tools to investigate this issue is ratio fluxes for secondary and primary species. boron-to-carbon (B/C) ratio, particular, sensitive probe mechanisms. This paper presents new measurements absolute boron carbon nuclei, as well B/C from PAMELA space experiment. results span range 0.44 - 129 GeV/n kinetic energy data taken period July 2006 March 2008.
We report the observation of new properties primary iron (Fe) cosmic rays in rigidity range 2.65 GV to 3.0 TV with 0.62×106 nuclei collected by Alpha Magnetic Spectrometer experiment on International Space Station. Above 80.5 dependence ray Fe flux is identical He, C, and O fluxes, Fe/O ratio being constant at 0.155±0.006. This shows that unexpectedly belong same class which different from Ne, Mg, Si class.Received 2 October 2020Revised 22 November 2020Accepted 9 December...
We present high-statistics, precision measurements of the detailed time and energy dependence primary cosmic-ray electron flux positron over 79 Bartels rotations from May 2011 to 2017 in range 1 50 GeV. For first time, charge-sign dependent modulation during solar maximum has been investigated detail by leptons alone. Based on 23.5×10^{6} events, we report observation short-term structures timescale months coincident both flux. These are not visible e^{+}/e^{-} ratio. The across polarity...
A precision measurement of the nitrogen flux with rigidity (momentum per unit charge) from 2.2 GV to 3.3 TV based on 2.2×10^{6} events is presented. The detailed dependence spectral index presented for first time. rapidly hardens at high rigidities and becomes identical indices primary He, C, O cosmic rays above ∼700 GV. We observed that Φ_{N} can be as sum its component Φ_{N}^{P} secondary Φ_{N}^{S}, Φ_{N}=Φ_{N}^{P}+Φ_{N}^{S}, we found well described by weighted oxygen Φ_{O} (primary rays)...
We report the observation of new properties primary cosmic rays, neon (Ne), magnesium (Mg), and silicon (Si), measured in rigidity range 2.15 GV to 3.0 TV with 1.8×10^{6} Ne, 2.2×10^{6} Mg, 1.6×10^{6} Si nuclei collected by Alpha Magnetic Spectrometer experiment on International Space Station. The Ne Mg spectra have identical dependence above 3.65 GV. three 86.5 GV, deviate from a single power law 200 harden an way. Unexpectedly, rays is different He, C, O. This shows that O are two classes rays.
We present the precision measurement of daily proton fluxes in cosmic rays from May 20, 2011 to October 29, 2019 (a total 2824 days or 114 Bartels rotations) rigidity interval 1 100 GV based on 5.5×10^{9} protons collected with Alpha Magnetic Spectrometer aboard International Space Station. The exhibit variations multiple timescales. From 2014 2018, we observed recurrent flux a period 27 days. Shorter periods 9 and 13.5 are 2016. strength all three periodicities changes time rigidity....
We present the space spectrometer PAMELA observations of proton and helium fluxes during December 13 14, 2006 solar particle events. This is first direct measurement energetic particles in with a single instrument energy range from $\sim$ 80 MeV/n up to 3 GeV/n. In event measured spectra protons were compared results obtained by neutron monitors other detectors. Our measurements show spectral behaviour different those derived monitor network. No satisfactory analytical fitting was found for...
Precision measurements by the Alpha Magnetic Spectrometer (AMS) on International Space Station of ^{3}He and ^{4}He fluxes are presented. The based 100 million nuclei in rigidity range from 2.1 to 21 GV 18 1.9 15 collected May 2011 November 2017. We observed that exhibit nearly identical variations with time. relative magnitude decreases increasing rigidity. dependence ^{3}He/^{4}He flux ratio is measured for first Below 4 GV, was found have a significant long-term time dependence. Above be...
We present the precision measurement of 2824 daily helium fluxes in cosmic rays from May 20, 2011 to October 29, 2019 rigidity interval 1.71 100 GV based on 7.6×10^{8} nuclei collected with Alpha Magnetic Spectrometer (AMS) aboard International Space Station. The flux and proton ratio exhibit variations multiple timescales. In nearly all time intervals 2014 2018, we observed recurrent a period 27 days. Shorter periods 9 days 13.5 are 2016. strength three periodicities changes rigidity....
We present the precision measurements of 11 years daily cosmic electron fluxes in rigidity interval from 1.00 to 41.9 GV based on 2.0×10^{8} electrons collected with Alpha Magnetic Spectrometer (AMS) aboard International Space Station. The exhibit variations multiple timescales. Recurrent flux periods 27 days, 13.5 and 9 days are observed. find that show distinctly different time proton fluxes. Remarkably, a hysteresis between is observed significance greater than 6σ at rigidities below 8.5...