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1.
  • Adriani, O., et al. (author)
  • Measurement of Boron and Carbon Fluxes in Cosmic Rays with the Pamela Experiment
  • 2014
  • In: Astrophysical Journal. - 0004-637X .- 1538-4357. ; 791:2, s. 93-
  • Journal article (peer-reviewed)abstract
    • The propagation of cosmic rays inside our galaxy plays a fundamental role in shaping their injection spectra into those observed at Earth. One of the best tools to investigate this issue is the ratio of fluxes for secondary and primary species. The boron-to-carbon (B/C) ratio, in particular, is a sensitive probe to investigate propagation mechanisms. This paper presents new measurements of the absolute fluxes of boron and carbon nuclei as well as the B/C ratio from the PAMELA space experiment. The results span the range 0.44-129 GeV/n in kinetic energy for data taken in the period 2006 July to 2008 March.
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2.
  • Adriani, O., et al. (author)
  • Measurement of the flux of primary cosmic ray antiprotons with energies of 60 MeV to 350 GeV in the PAMELA experiment
  • 2013
  • In: JETP Letters. - 0021-3640 .- 1090-6487. ; 96:10, s. 621-627
  • Journal article (peer-reviewed)abstract
    • It is interesting to measure the antiproton galactic component in cosmic rays in order to study the mechanisms by which particles and antiparticles are generated and propagate in the Galaxy and to search for new sources of, e.g., annihilation or decay of dark matter hypothetical particles. The antiproton spectrum and the ratio of the fluxes of primary cosmic ray antiprotons to protons with energies of 60 MeV to 350 GeV found from the data obtained from June 2006 to January 2010 in the PAMELA experiment are presented. The usage of the advanced data processing method based on the data classification mathematical model made it possible to increase statistics and analyze the region of higher energies than in the earlier works.
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3.
  • Casolino, M., et al. (author)
  • New upper limit on strange quark matter flux with the PAMELA experiment
  • 2013
  • In: Proceedings of the 33rd International Cosmic Rays Conference, ICRC 2013. - : Sociedade Brasileira de Fisica. - 9788589064293
  • Conference paper (peer-reviewed)abstract
    • In this work we present a new upper limit for anomalous charge / mass (Z/A) particles with PAMELA experiment. These particles would exhibit a low velocity in the Time-of-Flight system and an high rigidity in the tracker. The redundant nature of the PAMELA detectors make it particularly suited to search for these particles in a mass number (10 ≤ A ≤ 105), charge (1≤ Z ≤ 8) and rigidity (0.4 ≤ R ≤ 1200 GV) range complementary to those of ground-based experiments. 
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4.
  • Koldobskiy, S. A., et al. (author)
  • Deuteron spectrum measurements under radiation belt with PAMELA instrument
  • 2016
  • In: Nuclear and Particle Physics Proceedings. - : Elsevier. - 2405-6014. ; 273-275, s. 2345-2347
  • Journal article (peer-reviewed)abstract
    • In this work the results of data analysis of the deuteron albedo radiation obtained in the PAMELA experiment are presented. PAMELA is an international space experiment carried out on board of the satellite Resurs DK-1. The high precision detectors allow to register and identify cosmic ray particles in a wide energy range. The albedo deuteron spectrum in the energy range 70 - 600 MeV/nucleon has been measured.
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5.
  • Koldobskiy, S., et al. (author)
  • Measuring the albedo deuteron flux in the PAMELA satellite experiment
  • 2015
  • In: Bulletin of the Russian Academy of Sciences: Physics. - 1062-8738. ; 79:3, s. 294-297
  • Journal article (peer-reviewed)abstract
    • The results of measuring albedo deuteron fluxes in the vicinity of the Earth are presented. The data were obtained in the PAMELA experiment conducted aboard the Resurs DK-1 artificial Earth satellite. High-precision detectors of the instrument setup allow us to identify albedo deuterons and measure their spectra in the energy interval from 70 to 600 MeV/nucleon at altitudes of 350–600 km for different geomagnetic latitudes.
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6.
  • Merge, M., et al. (author)
  • Multi-particle analysis of the december 13th 2006 forbush decrease with PAMELA experiment
  • 2013
  • In: Proceedings of the 33rd International Cosmic Rays Conference, ICRC 2013. - : Sociedade Brasileira de Fisica. - 9788589064293
  • Conference paper (peer-reviewed)abstract
    • In this paper we present PAMELA multi-particle observation of the Forbush decrease (FD) following the December 13th 2006 solar particle event. The FD is the sudden decrease of the galactic cosmic ray flux due to the transit of a Coronal Mass Ejection (CME). The satellite-borne experiment PAMELA on-board Resurs-DK1 satellite and consist of a magnetic spectrometer with time-of-flight and calorimeter detectors. PAMELA can study in real time with high precision the temporal and energetic evolution of several particle fluence during and after crossing of the magnetic cloud generated by the CME. The effect is stronger than what detected on ground with neutron monitor. With flux reduction can be as high as 30% decreasing at 1.5GV. No difference of the FD has been found for different particles proving that there is no charge sign dependence of FD for this event. 
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7.
  • Mikhailov, V., et al. (author)
  • Measurements of electron and positron fluxes below the geomagnetic cutoff by the PAMELA magnetic spectrometer
  • 2017
  • In: Proceedings of Science. - : Sissa Medialab Srl.
  • Conference paper (peer-reviewed)abstract
    • We present a measurements of electron and positron fluxes below the geomagnetic cutoff rigidity in wide energy range from 50 MeV to several GeVs by the PAMELA magnetic spectrometer. The instrument was launched on June 15th 2006 on-board the Resurs-DK satellite on low orbit with 70 degrees inclination and altitude between 350 and 600 km. Features of spatial distributions of secondary electrons and positrons in the near Earth space, including the South Atlantic Anomaly, were investigated in terms of lifetime and geographical origin. The separation in stably trapped, long lifetime quasi-trapped, and short lifetime albedo components was performed on base of back tracing procedure in geomagnetic field. A significant difference in relative abundance of positrons with respect to electrons is seen for the stable trapped and the quasi-trapped populations what pointing out on differences in trapping mechanism of those populations. 
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8.
  • Mori, N., et al. (author)
  • The PAMELA experiment and cosmic ray observations
  • 2015
  • In: NUCLEAR AND PARTICLE PHYSICS PROCEEDINGS. - : Elsevier. - 2405-6014. ; , s. 242-244
  • Conference paper (peer-reviewed)abstract
    • The PAMELA space experiment is aimed at precise measurements of the charged light component of the cosmic ray spectrum in the energy range spanning from the sub-GeV region to the TeV region, with a particular focus on antimatter. The instrument consists of a magnetic spectrometer, an electromagnetic sampling calorimeter,a time-off-light system, an anticoincidence shield, a tail-catcher scintillator and a neutron detector. Launched in June 2006 and hosted on the Resurs-DK1 satellite, PAMELA has been taking data for more than eight years, providing scientific results with unprecedented statistics and a continuous monitoring of the sun activity and the heliosphere.
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9.
  • Munini, R., et al. (author)
  • Solar modulation of galactic cosmic rays electrons and positrons over the 23rd solar minimum with the pamela experiment
  • 2013
  • In: Proceedings of the 33rd International Cosmic Rays Conference, ICRC 2013. - : Sociedade Brasileira de Fisica. - 9788589064293
  • Conference paper (peer-reviewed)abstract
    • The satellite-borne PAMELA experiment has been continuously collecting data since 15th June 2006, when it was launched from the Baikonur cosmodrome to detect the charged component of cosmic rays over a wide energy range and with an unprecedented statistics. The apparatus design is particularly suited for particle and antiparticle identification. The satellite quasi-polar orbit, with an inclination of 70 degrees, allows particles to be measure down to 100 MeV/n. This makes the instrument suited for the investigation of phenomena related to galactic cosmic ray solar modulation in the inner heliosphere. Data for oppositely charged particles were collected from 2006 to 2009, during the A< 0 solar minimum of solar cycle 23. The time and rigidity dependence of galactic cosmic ray electron and positron fluxes were measured. These fluxes provide important information for the study of charge dependent solar modulation effects. 
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10.
  • Usoskin, I. G., et al. (author)
  • Force-field parameterization of the galactic cosmic ray spectrum : Validation for Forbush decreases
  • 2015
  • In: Advances in Space Research. - : Elsevier BV. - 0273-1177 .- 1879-1948. ; 55:12, s. 2940-2945
  • Journal article (peer-reviewed)abstract
    • A useful parametrization of the energy spectrum of galactic cosmic rays (GCR) near Earth is offered by the so-called force-field model which describes the shape of the entire spectrum with a single parameter, the modulation potential. While the usefulness of the force-field approximation has been confirmed for regular periods of solar modulation, it was not tested explicitly for disturbed periods, when GCR are locally modulated by strong interplanetary transients. Here we use direct measurements of protons and alpha-particles performed by the PAMELA space-borne instrument during December 2006, including a major Forbush decrease, in order to directly test the validity of the force-field parameterization. We conclude that (1) The force-field parametrization works very well in describing the energy spectra of protons and alpha-particles directly measured by PAMELA outside the Earths atmosphere; (2) The energy spectrum of GCR can be well parameterized by the force-field model also during a strong Forbush decrease; (3) The estimate of the GCR modulation parameter, obtained using data from the world-wide neutron monitor network, is in good agreement with the spectra directly measured by PAMELA during the studied interval. This result is obtained on the basis of a single event analysis, more events need to be analyzed.
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11.
  • Adriani, O., et al. (author)
  • Antiprotons in primary cosmic radiation with PAMELA experiment
  • 2013
  • In: Proceedings of the 33rd International Cosmic Rays Conference, ICRC 2013. - : Sociedade Brasileira de Fisica. - 9788589064293
  • Conference paper (peer-reviewed)abstract
    • The latest measurements of antiprotons spectrum and antiproton-to-proton ratio in primary cosmic rays with PAMELA experiment are presented. They are in good agreement with model of secondary production of antiprotons in Galaxy, but they do not completely rule other sources at the high-energies. 
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12.
  • Adriani, O., et al. (author)
  • Cosmic-Ray Positron Energy Spectrum Measured by PAMELA
  • 2013
  • In: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 111:8, s. 081102-
  • Journal article (peer-reviewed)abstract
    • Precision measurements of the positron component in the cosmic radiation provide important information about the propagation of cosmic rays and the nature of particle sources in our Galaxy. The satellite-borne experiment PAMELA has been used to make a new measurement of the cosmic-ray positron flux and fraction that extends previously published measurements up to 300 GeV in kinetic energy. The combined measurements of the cosmic-ray positron energy spectrum and fraction provide a unique tool to constrain interpretation models. During the recent solar minimum activity period from July 2006 to December 2009, approximately 24 500 positrons were observed. The results cannot be easily reconciled with purely secondary production, and additional sources of either astrophysical or exotic origin may be required.
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13.
  • Adriani, O., et al. (author)
  • Measurement of the isotopic composition of hydrogen and helium nuclei in cosmic rays with the PAMELA experiment
  • 2013
  • In: Astrophysical Journal. - : IOP Publishing. - 0004-637X .- 1538-4357. ; 770:1, s. 2-
  • Journal article (peer-reviewed)abstract
    • The satellite-borne experiment PAMELA has been used to make new measurements of cosmic ray H and He isotopes. The isotopic composition was measured between 100 and 600 MeV /n for hydrogen and between 100 and 900 MeV /n for helium isotopes over the 23rd solar minimum from 2006 July to 2007 December. The energy spectrum of these components carries fundamental information regarding the propagation of cosmic rays in the galaxy which are competitive with those obtained from other secondary to primary measurements such as B/C.
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14.
  • Adriani, O., et al. (author)
  • Measurements of cosmic-ray proton and helium spectra with the PAMELA calorimeter
  • 2013
  • In: Advances in Space Research. - : Elsevier BV. - 0273-1177 .- 1879-1948. ; 51:2, s. 219-226
  • Journal article (peer-reviewed)abstract
    • We present a new measurement of the cosmic ray proton and helium spectra by the PAMELA experiment performed using the "thin" (in terms of nuclei interactions) sampling electromagnetic calorimeter. The described method, optimized by using Monte Carlo simulation, beam test and experimental data, allows the spectra to be measured up to 10 TeV, thus extending the PAMELA observational range based on the magnetic spectrometer measurement.
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15.
  • Adriani, O., et al. (author)
  • Measurements of quasi-trapped electron and positron fluxes with PAMELA
  • 2009
  • In: Journal of Geophysical Research. - 0148-0227 .- 2156-2202. ; 114, s. A12218-
  • Journal article (peer-reviewed)abstract
    • This paper presents precise measurements of the differential energy spectra of quasi-trapped secondary electrons and positrons and their ratio between 80 MeV and 10 GeV in the near-equatorial region (altitudes between 350 km and 600 km). Latitudinal dependences of the spectra are analyzed in detail. The results were obtained from July until November 2006 onboard the Resurs-DK satellite by the PAMELA spectrometer, a general purpose cosmic ray detector system built around a permanent magnet spectrometer and a silicon-tungsten calorimeter.
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16.
  • Adriani, O., et al. (author)
  • Pamela's measurements of magnetospheric effects on high-energy solar particles
  • 2015
  • In: Astrophysical Journal Letters. - 2041-8205 .- 2041-8213. ; 801:1
  • Journal article (peer-reviewed)abstract
    • The nature of particle acceleration at the Sun, whether through flare reconnection processes or through shocks driven by coronal mass ejections, is still under scrutiny despite decades of research. The measured properties of solar energetic particles (SEPs) have long been modeled in different particle-acceleration scenarios. The challenge has been to disentangle the effects of transport from those of acceleration. The Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics (PAMELA) instrument enables unique observations of SEPs including the composition and angular distribution of the particles about the magnetic field, i.e., pitch angle distribution, over a broad energy range (>80 MeV)-bridging a critical gap between space-based and ground-based measurements. We present high-energy SEP data from PAMELA acquired during the 2012 May 17 SEP event. These data exhibit differential anisotropies and thus transport features over the instrument rigidity range. SEP protons exhibit two distinct pitch angle distributions: a low-energy population that extends to 90 degrees and a population that is beamed at high energies (>1 GeV), consistent with neutron monitor measurements. To explain a low-energy SEP population that exhibits significant scattering or redistribution accompanied by a high-energy population that reaches the Earth relatively unaffected by dispersive transport effects, we postulate that the scattering or redistribution takes place locally. We believe that these are the first comprehensive measurements of the effects of solar energetic particle transport in the Earth's magnetosheath.
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17.
  • Adriani, O., et al. (author)
  • Reentrant albedo proton fluxes measured by the PAMELA experiment
  • 2015
  • In: Journal of Geophysical Research - Space Physics. - 2169-9380 .- 2169-9402. ; 120:5, s. 3728-3738
  • Journal article (peer-reviewed)abstract
    • We present a precise measurement of downward going albedo proton fluxes for kinetic energy above similar to 70 MeV performed by the Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics (PAMELA) experiment at an altitude between 350 and 610 km. On the basis of a trajectory tracing simulation, the analyzed protons were classified into quasi-trapped, concentrating in the magnetic equatorial region, and untrapped spreading over all latitudes, including both short-lived (precipitating) and long-lived (pseudotrapped) components. In addition, features of the penumbra region around the geomagnetic cutoff were investigated in detail. PAMELA results significantly improve the characterization of the high-energy albedo proton populations at low-Earth orbits.
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18.
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19.
  • Adriani, O., et al. (author)
  • Time Dependence of the Electron and Positron Components of the Cosmic Radiation Measured by the PAMELA Experiment between July 2006 and December 2015
  • 2016
  • In: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 116:24
  • Journal article (peer-reviewed)abstract
    • Cosmic-ray electrons and positrons are a unique probe of the propagation of cosmic rays as well as of the nature and distribution of particle sources in our Galaxy. Recent measurements of these particles are challenging our basic understanding of the mechanisms of production, acceleration, and propagation of cosmic rays. Particularly striking are the differences between the low energy results collected by the space-borne PAMELA and AMS-02 experiments and older measurements pointing to sign-charge dependence of the solar modulation of cosmic-ray spectra. The PAMELA experiment has been measuring the time variation of the positron and electron intensity at Earth from July 2006 to December 2015 covering the period for the minimum of solar cycle 23 (2006-2009) until the middle of the maximum of solar cycle 24, through the polarity reversal of the heliospheric magnetic field which took place between 2013 and 2014. The positron to electron ratio measured in this time period clearly shows a sign-charge dependence of the solar modulation introduced by particle drifts. These results provide the first clear and continuous observation of how drift effects on solar modulation have unfolded with time from solar minimum to solar maximum and their dependence on the particle rigidity and the cyclic polarity of the solar magnetic field.
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20.
  • Bogomolov, E. A., et al. (author)
  • Spectra of solar neutrons with energies of ~10–1000 MeV in the PAMELA experiment in the flare events of 2006–2015
  • 2017
  • In: Bulletin of the Russian Academy of Sciences: Physics. - : Allerton Press Incorporation. - 1062-8738. ; 81:2, s. 132-135
  • Journal article (peer-reviewed)abstract
    • The first results from measuring the spectra of solar neutrons with energies of ~10–1000 MeV in the solar flares of 2006–2015 observed by the PAMELA international space experiment are presented. The PAMELA neutron detector with 3He counters and a moderator with an area of 0.18 m2 allows us to estimate the flux of solar neutrons during solar flares. Solar neutrons with energies of ~10–1000 MeV likely occurred in 21 out of the 24 analyzed flares of 2006–2015.
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21.
  • Bruno, A., et al. (author)
  • Geomagnetically trapped, albedo and solar energetic particles : Trajectory analysis and flux reconstruction with PAMELA
  • 2017
  • In: Advances in Space Research. - : Elsevier. - 0273-1177 .- 1879-1948. ; 60:4, s. 788-795
  • Journal article (peer-reviewed)abstract
    • The PAMELA satellite experiment is providing comprehensive observations of the interplanetary and magnetospheric radiation in the near-Earth environment. Thanks to its identification capabilities and the semi-polar orbit, PAMELA is able to precisely measure the energetic spectra and the angular distributions of the different cosmic-ray populations over a wide latitude region, including geomagnetically trapped and albedo particles. Its observations comprise the solar energetic particle events between solar cycles 23 and 24, and the geomagnetic cutoff variations during magnetospheric storms. PAMELA's measurements are supported by an accurate analysis of particle trajectories in the Earth's magnetosphere based on a realistic geomagnetic field modeling, which allows the classification of particle populations of different origin and the investigation of the asymptotic directions of arrival.
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22.
  • Bruno, A., et al. (author)
  • PAMELA's measurements of geomagnetic cutoff variations during solar energetic particle events
  • 2015
  • In: Proceedings of Science. - : Proceedings of Science (PoS).
  • Conference paper (peer-reviewed)abstract
    • Data from the PAMELA satellite experiment were used to measure the geomagnetic cutoff for high-energy ( 80 MeV) protons during the solar particle events on 2006 December 13 and 14. The variations of the cutoff latitude as a function of rigidity were studied on relatively short timescales, corresponding to single spacecraft orbits (about 94 minutes). Estimated cutoff values were cross-checked with those obtained by means of a trajectory tracing approach based on dynamical empirical modeling of the Earth's magnetosphere. We find significant variations in the cutoff latitude, with a maximum suppression of about 6 deg for 80 MeV protons during the main phase of the storm. The observed reduction in the geomagnetic shielding and its temporal evolution were compared with the changes in the magnetosphere configuration, investigating the role of IMF, solar wind and geomagnetic (Kp, Dst and Sym-H indexes) variables and their correlation with PAMELA cutoff results.
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23.
  • Bruno, A., et al. (author)
  • PAMELA's measurements of geomagnetically trapped and albedo protons
  • 2015
  • In: Proceedings of Science. - : Proceedings of Science (PoS).
  • Conference paper (peer-reviewed)abstract
    • Data from the PAMELA satellite experiment were used to perform a detailed measurement of under-cutoff protons at low Earth orbits. On the basis of a trajectory tracing approach using a realistic description of the magnetosphere, protons were classified into geomagnetically trapped and re-entrant albedo. The former include stably-trapped protons in the South Atlantic Anomaly, which were analyzed in the framework of the adiabatic theory, investigating energy spectra, spatial and angular distributions; results were compared with the predictions of the AP8 and the PSB97 empirical trapped models. The albedo protons were classified into quasi-trapped, concentrating in the magnetic equatorial region, and un-trapped, spreading over all latitudes and including both short-lived (precipitating) and long-lived (pseudo-trapped) components. Features of the penumbra region around the geomagnetic cutoff were investigated as well. PAMELA observations significantly improve the characterization of the high energy proton populations in near Earth orbits. The.
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24.
  • Bruno, A., et al. (author)
  • Solar energetic particle events : Trajectory analysis and flux reconstruction with PAMELA
  • 2015
  • In: Proceedings of Science. - : Proceedings of science.
  • Conference paper (peer-reviewed)abstract
    • The PAMELA satellite experiment is providing first direct measurements of Solar Energetic Particles (SEPs) with energies from about 80 MeV to several GeV in near-Earth space, bridging the low energy data by other space-based instruments and the Ground Level Enhancement (GLE) data by the worldwide network of neutron monitors. Its unique observational capabilities include the possibility of measuring the flux angular distribution and thus investigating possible anisotropies. This work reports the analysis methods developed to estimate the SEP energy spectra as a function of the particle pitch-angle with respect to the Interplanetary Magnetic Field (IMF) direction. The crucial ingredient is provided by an accurate simulation of the asymptotic exposition of the PAMELA apparatus, based on a realistic reconstruction of particle trajectories in the Earth's magnetosphere. As case study, the results for the May 17, 2012 event are presented.
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25.
  • Carbone, R., et al. (author)
  • Pamela observation of the 2012 may 17 gle event
  • 2013
  • In: Proceedings of the 33rd International Cosmic Rays Conference, ICRC 2013. - : Sociedade Brasileira de Fisica. - 9788589064293
  • Conference paper (peer-reviewed)abstract
    • The PAMELA (Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics) satellite-borne experiment has been collecting data in orbit since July 2006, providing accurate measurements of the energy spectra and composition of the cosmic radiation from a few hundred MeV/n up to hundred GeV/n. This wide interval of measured energies makes PAMELA a unique instrument for Solar Energetic Particle (SEP) observations. Not only does it span the energy range between the ground-based neutron monitor data and the observations of SEPs from space, but also PAMELA carries out the first direct measurements of the composition for the highest energy SEP events, including those causing Ground Level Enhancements (GLEs). PAMELA has registered many SEP events in solar cycle 24 including the 2012 May 17 GLE event (GLE 71), offering unique opportunities to address the question of high-energy SEP origin. Experimental performances and preliminary results on the 2012 May 17 events will be presented. We will discuss the derived particle injection time and compare with other time scales at the Sun including the flare and CME onset times. 
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26.
  • Formato, V., et al. (author)
  • Galactic boron and carbon fluxes measured by the PAMELA experiment
  • 2013
  • In: Proceedings of the 33rd International Cosmic Rays Conference, ICRC 2013. - : Sociedade Brasileira de Fisica. - 9788589064293
  • Conference paper (peer-reviewed)abstract
    • The PAMELA experiment is a satellite-borne apparatus that performs measurements of the cosmic radiation with a particular focus on antiparticles and light nuclei. The heart of experiment is a magnetic spectrometer to measure the particle rigidity and sign of charge. A Time-of-Flight system, a Silicon-Tungsten calorimeter, and a neutron detector allow particle identification and lepton/hadron discrimination. The apparatus is surrounded by a set of anticoincidence scintillation counters to reject multi-particle events. In this work we will present the Boron and Carbon fluxes measured by PAMELA from July 2006 to March 2008. Such data, and in particular the B/C flux ratio, can help the modelling of the galactic cosmic rays propagation. This can be a crucial point in predicting the astrophysical background of antimatter (positrons and antiprotons) in cosmic rays in the search for a dark matter signal. 
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27.
  • Formato, V., et al. (author)
  • Hydrogen and helium isotopes flux in cosmic rays with the PAMELA experiment
  • 2013
  • In: Proceedings of the 33rd International Cosmic Rays Conference, ICRC 2013. - : Sociedade Brasileira de Fisica. - 9788589064293
  • Conference paper (peer-reviewed)abstract
    • PAMELA is a satellite borne experiment designed to study with great accuracy cosmic rays of galactic, solar, and trapped nature, with particular focus on the antimatter component. The detector consists of a permanent magnet spectrometer core to provide rigidity and charge sign information, a Time-of-Flight system for velocity and charge information, a Silicon-Tungsten calorimeter and a Neutron detector for lepton/hadron identification. The beta and rigidity information allow to identify isotopes for Z = 1 and Z = 2 particles in the energy range 100 MeV/n to 1 GeV/n. In this work we will present the final PAMELA results on the H and He isotope fluxes measured during the 23rd solar minimum from 2006 to 2007. Such fluxes carry relevant information helpful in constraining parameters in galactic cosmic rays propagation models complementary to those obtained from other secondary to primary measurements such as the boron-to-carbon ratio. 
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28.
  • Galper, A. M., et al. (author)
  • The PAMELA experiment : A decade of Cosmic Ray Physics in space
  • 2017
  • In: Journal of Physics, Conference Series. - : Institute of Physics Publishing (IOPP). - 1742-6588 .- 1742-6596. ; 798:1
  • Journal article (peer-reviewed)abstract
    • The PAMELA detector was launched on June 15 th of 2006 on board the Russian Resurs-DK1 satellite and during ten years of continuous data-taking it has observed very interesting features in cosmic rays, especially in the fluxes of protons, helium and electrons. Moreover, PAMELA measurements of cosmic antiproton and positron fluxes and positron-to-all-electron ratio have set strong constraints to the nature of Dark Matter. Measurements of boron, carbon, lithium and beryllium (together with the isotopic fraction) have also shed new light on the elemental composition of the cosmic radiation. Search for signatures of more exotic processes (such as the ones involving Strange Quark Matter) has also been pursued. Furthermore, over the years the instrument has allowed a constant monitoring of the solar activity and a prolonged study of the solar modulation, improving the comprehension of the heliosphere mechanisms. PAMELA has also measured the radiation environment around the Earth, and detected for the first time the presence of an antiproton radiation belt surrounding our planet. In this highlight paper PAMELA main results will be reviewed.
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29.
  • Koldobskiy, S. A., et al. (author)
  • Galactic deuteron spectrum measured in PAMELA experiment
  • 2013
  • In: 23Rd European Cosmic Ray Symposium (And 32Nd Russian Cosmic Ray Conference). - : IOP Publishing.
  • Conference paper (peer-reviewed)abstract
    • Results of galactic deuteron spectrum measurement by means of PAMELA apparatus are described. PAMELA is an international experiment developed for antimatter search and measurement of p, He, electron and positron spectra in wide energy range. In addition, PAMELA allows to identify and measure deuteron spectrum at low energies. In this paper deuteron-to-proton ratio and deuteron spectrum are presented.
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30.
  • Koldobskiy, S. A., et al. (author)
  • Measurement of galactic cosmic-ray deuteron spectrum in the PAMELA experiment
  • 2013
  • In: Bulletin of the Russian Academy of Sciences: Physics. - : Allerton Press. - 1062-8738. ; 77:5, s. 606-608
  • Journal article (peer-reviewed)abstract
    • This work presents the results of measuring the deuteron spectrum of Galactic cosmic rays (GCRs) with the PAMELA experiment. The PAMELA is an international experiment. Its main objectives are to search for antimatter and measure proton, helium nuclei, electron, and positron spectra over a wide range of energies. In addition, the experimental setup allows the detection of deuterons and the reconstruction of their spectra at low energies. Cosmic ray deuteron spectrum and the deuteron-proton ratio measured in the PAMELA experiment in the energy range of 50-650 MeV/nucleon are presented below.
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31.
  • Koldobskiy, S. A., et al. (author)
  • Measurement of trapped and quasitrapped deuteron populations in PAMELA experiment
  • 2015
  • In: Proceedings of Science. - : Proceedings of Science (PoS).
  • Conference paper (peer-reviewed)abstract
    • The results of measurements of trapped and albedo cosmic ray deuteron fluxes obtained in the PAMELA experiment are presented in this work. The PAMELA is an international experiment aimed for measurements of cosmic ray particle fluxes in wide energy range. In particular, analysis of PAMELA data gives possibility to identify deuterons and to reconstruct deuteron spectra of different origin (galactic cosmic ray, re-entrant albedo and radiation belt particles). The first results of trajcectory reconstruction for trapped and albedo deuterons are presented in this work. This investigation was done by solving equations of particle motion in Earth's magnetic field by means of numerical integration methods.
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32.
  • Koldobskiy, S. A., et al. (author)
  • Solar modulation of cosmic deuteron fluxes in the PAMELA experiment
  • 2017
  • In: Bulletin of the Russian Academy of Sciences: Physics. - : Allerton Press Incorporation. - 1062-8738. ; 81:2, s. 151-153
  • Journal article (peer-reviewed)abstract
    • The preliminary results from measurements of deuteron fluxes in galactic cosmic rays (GCR) in the vicinity of the Earth in 2006–2009 are presented. The results are obtained by analyzing data from the PAMELA experiment aboard the Resurs DK-1 satellite. High-precision detection instruments provided an opportunity to identify GCR deuterons and measure their spectrum in the energy interval of 90–650MeV/nucleon. Spectra averaged over six-month intervals from the summer of 2006 to the summer of 2009 (the solar activity minimum) are presented. The influence of solar modulation on the observed spectrum is clearly seen in the results.
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33.
  • Menn, W., et al. (author)
  • Cosmic-ray lithium and beryllium isotopes in the PAMELA-experiment
  • 2017
  • In: Proceedings of Science. - : Sissa Medialab Srl.
  • Conference paper (peer-reviewed)abstract
    • The PAMELA space experiment was launched on the 15th of June 2006 from the Baikonur cosmodrome. The scientific objectives addressed by the mission are the measurement of the antiprotons and positrons spectra in cosmic rays, the hunt for antinuclei as well as the determination of light nuclei fluxes from hydrogen to oxygen in a wide energy range and with high statistics. The apparatus comprises a time-of-flight system, a magnetic spectrometer (permanent magnet) with an silicon-microstrip tracking system, an imaging calorimeter built from layers of siliconmicrostrip detectors interleaved with plates of tungsten, an anti-coincidence system, a shower tail scintillator-counter and a neutron detector. The instrument in its detector-combination is also capable to identify isotopes, using the rigidity information from the magnetic spectrometer together with the time-of-flight measurement or with the multiple dE/dx measurement in the calorimeter. In this paper details about the analysis method and new results of the isotopic ratios of lithium and beryllium with increased statistics will be presented. 
  •  
34.
  • Mergè, M., et al. (author)
  • PAMELA measurements of solar energetic particle spectra
  • 2017
  • In: Proceedings of Science. - : Sissa Medialab Srl.
  • Conference paper (peer-reviewed)abstract
    • The charged particle acceleration and transport during solar events have been widely studied in the past decades. The satellite-borne PAMELA experiment has been continuously collecting data since 2006. The apparatus is designed to study charged particles in the cosmic radiation. The combination of permanent magnet, silicon micro-strip spectrometer and silicon-tungsten imaging calorimeter, with the redundancy of instrumentation allows very precise studies on the physics of cosmic rays in a wide energy range and with high statistics. This makes PAMELA a well suited instrument for Solar Energetic Particles (SEP) observations. Not only it spans the energy range between the ground-based neutron monitor data and the observations of SEPs from space, but also PAMELA carries out the first direct measurements of SEP energy spectra, composition and angular distribution. PAMELA has observed many SEP events in solar cycle 24, offering unique opportunity to address several questions on high-energy SEP origin. A preliminary analysis on proton spectra during several events of the 24th solar cycle is presented. 
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35.
  • Mikhailov, V. V., et al. (author)
  • Cosmic ray electrons and positrons over decade with the PAMELA experiment
  • 2019
  • In: Journal of Physics. - : Institute of Physics Publishing.
  • Conference paper (peer-reviewed)abstract
    • The PAMELA experiment has measured cosmic ray particles and antiparticles fluxes at Earth orbit from June 2006 till January 2016 onboard the Resurs-DK1 satellite. Measurements were carried out during the solar minimum of 23 solar cycle with negative polarity A < 0 of heliospheric magnetic field till the beginning of 24 cycle with positive polarity A > 0. In this paper, the results of observations of electron and positron fluxes are presented in wide energy range from several hundreds MeVs till several TeVs These measurements provide important information to study cosmic ray sources and propagation in Galaxy and heliosphere.
  •  
36.
  • Mikhailov, V. V., et al. (author)
  • Galactic Cosmic Ray Electrons and Positrons over a Decade of Observations in the PAMELA Experiment
  • 2019
  • In: Bulletin of the Russian Academy of Sciences: Physics. - : Pleiades Publishing. - 1062-8738. ; 83:8, s. 974-976
  • Journal article (peer-reviewed)abstract
    • The PAMELA magnetic spectrometer was launched onboard the Resurs-DK1 satellite into a near-polar Earth orbit with an altitude of 350–600 km, in order to study fluxes of cosmic ray particles and antiparticles in the wide energy range of ~80 MeV to hundreds of GeV. The results from observations of electron and positron fluxes in 2006–2016 are presented.
  •  
37.
  • Mikhailov, V. V., et al. (author)
  • Method of electrons and positrons separations by bremsstrahlung in the PAMELA experiment
  • 2013
  • In: Proceedings of the 33rd International Cosmic Rays Conference, ICRC 2013. - : Sociedade Brasileira de Fisica. - 9788589064293
  • Conference paper (peer-reviewed)abstract
    • Imaging calorimeter of the PAMELA instrument on board the Resurs DK satellite has high spatial resolution and allows to measure separately electromagnetic showers from electrons and positrons and their bremsstahlung produced in ToF detectors of the instrument. Measuring events with two showers provides proton rejection coefficient more than 104 at energy between 0.5 and 3 GeV. Results of positrons fractions obtained by this method are in agreement with previously published data of the PAMELA experiment at low energy. It confirms in independent way strong positron modulation during period of negative polarity of the Sun magnetic field.
  •  
38.
  • Mikhailov, V. V., et al. (author)
  • Modulation of electrons and positrons in 2006–2015 in the PAMELA experiment
  • 2017
  • In: Bulletin of the Russian Academy of Sciences: Physics. - : Allerton Press Incorporation. - 1062-8738. ; 81:2, s. 154-156
  • Journal article (peer-reviewed)abstract
    • The PAMELA magnetic spectrometer was launched aboard the Resurs DK-1 satellite into a nearpolar circumterrestrial orbit with an altitude of 350–600 km to study fluxes of the particles and antiparticles of cosmic rays in the wide energy range of ~80 MeV to several hundred gigaelectronvolts. The results from observations of temporal variations in electron and positron fluxes in 2006–2015 are presented. The ratio of electron and positron fluxes measured in this time interval reveals a dependence on the rigidity of particles, the solar activity, and the polarity of the solar magnetic field.
  •  
39.
  • Mikhailov, V. V., et al. (author)
  • Searching for anisotropy of positrons and electrons in the PAMELA experiment
  • 2015
  • In: Bulletin of the Russian Academy of Sciences: Physics. - 1062-8738. ; 79:3, s. 298-301
  • Journal article (peer-reviewed)abstract
    • The PAMELA experiment has been under way aboard the Resurs DK-1 satellite since June 2006. The results have revealed an increase in the ratio of the positron intensity to the total electron and positron intensity at energies in excess of 10 GeV. This increase suggests an additional source of cosmic rays that is associated with either some astrophysical objects (e.g., pulsars) or the probable annihilation of particles of dark matter. Local positron sources can produce notable anisotropy in their flux. The results from the search for anisotropy of positrons and electrons in the events detected by the PAMELA experiment in the 2006–2013 timeframe are described in detail in this work.
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40.
  • Mikhailov, V. V., et al. (author)
  • Secondary positrons and electrons in near-Earth space in the PAMELA experiment
  • 2017
  • In: Bulletin of the Russian Academy of Sciences: Physics. - : Allerton Press Incorporation. - 1062-8738. ; 81:2, s. 203-205
  • Journal article (peer-reviewed)abstract
    • Fluxes of electrons and positrons with energies above ~100 MeV in the near-Earth space are measured with the PAMELA magnetic spectrometer aboard the Resurs DK-1 satellite launched on June 15, 2006, into a quasipolar orbit with an altitude of 350–600 km and an inclination of 70°. Calculating the trajectories of detected electrons and positrons in the magnetosphere of the Earth allows us to determine their origin and isolate particles produced during interaction between cosmic rays and the residual atmosphere. Spatial distributions of albedo, quasitrapped, and trapped (in the radiation belt) positrons and electrons are presented. The ratio of positron and electron fluxes suggests that the fluxes of trapped particles of the radiation belt and quasitrapped secondary particles have different mechanisms of formation.
  •  
41.
  • Mikhailov, V. V., et al. (author)
  • Sharp increasing of positron to electron fluxes ratio below 2 GV measured by the PAMELA
  • 2017
  • In: Journal of Physics, Conference Series. - : Institute of Physics Publishing (IOPP). - 1742-6588 .- 1742-6596. ; 798:1
  • Journal article (peer-reviewed)abstract
    • Magnetic spectrometer PAMELA was launched onboard a satellite Resurs-DK1 into low-Earth polar orbit with altitude 350-600 km to study cosmic ray antiparticle fluxes in a wide energy range from ∼ 100 MeV to hundreds GeV. This paper presents the results of observations of temporal variations of the positron and electron fluxes in the 2006-2015. The ratio of the positron and electron fluxes below 2 GV shows sharp increasing since 2014 due to changing of the polarity of the solar magnetic field.
  •  
42.
  • Mikhailov, V. V., et al. (author)
  • Trapped Positrons and Electrons in the Inner Radiation Belt According to Data of the PAMELA Experiment
  • 2018
  • In: Physics of Atomic Nuclei. - : PLEIADES PUBLISHING INC. - 1063-7788 .- 1562-692X. ; 81:4, s. 515-519
  • Journal article (peer-reviewed)abstract
    • Measurements of secondary-electron and secondary-positron fluxes below the geomagnetic cutoff in near-Earth space were performed by means of the PAMELA magnetic spectrometer installed on board the Resurs-DK1 satellite launched on June 15, 2006, in an elliptical orbit of inclination 70A degrees and altitude 350 to 600 km. This spectrometer permits measuring the fluxes of electrons and positrons over a wide energy range, as well as determining their spatial distributions to a precision of about 2A degrees. A calculation of particle trajectories in the geomagnetic field makes it possible to separate electrons and positrons originating from cosmic-ray interactions in the Earth's magnetosphere. The spatial distributions of quasitrapped, trapped, and short-lived albedo positrons and electrons of energy above 70 MeV in the radiation belt were analyzed. The ratio of the electron-to-positron fluxes and the energy spectra of the electrons and positrons in question are indicative of different productionmechanisms for stably trapped and quasitrapped secondary particles.
  •  
43.
  • Mocchiutti, E., et al. (author)
  • Cosmic–ray positron energy spectrum measured by PAMELA
  • 2013
  • In: Proceedings of the 33rd International Cosmic Rays Conference, ICRC 2013. - : Sociedade Brasileira de Fisica. - 9788589064293
  • Conference paper (peer-reviewed)abstract
    • The PAMELA satellite borne experiment is designed to study cosmic rays with great accuracy in a wide energy range. One of PAMELA’s main goal is the study of the antimatter component of cosmic rays. The experiment, housed on board the Russian satellite Resurs–DK1, was launched on June 15th 2006 and it is still taking data. In this work we present the measurement of galactic positron energy spectrum in the energy range between 500 MeV and few hundred GeV. 
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44.
  • Mori, N., et al. (author)
  • PAMELA measurements of the boron and carbon spectra
  • 2015
  • In: 24TH EUROPEAN COSMIC RAY SYMPOSIUM (ECRS). - : IOP Publishing.
  • Conference paper (peer-reviewed)abstract
    • The satellite-borne PAMELA experiment is aimed at precision measurements of the charged light component of the cosmic-ray spectrum, with a particular focus on antimatter. It consists of a magnetic spectrometer, a time-of-flight system, an electromagnetic calorimeter with a tail catcher scintillating layer, an anticoincidence system and a neutron detector. PAMELA has measured the absolute fluxes of boron and carbon and the B/C ratio, which plays a central role in galactic propagation studies in order to derive the injection spectra at sources from measurements at Earth. In this paper, the data analysis techniques and the final results are presented.
  •  
45.
  • Munini, R., et al. (author)
  • Evidence of Energy and Charge Sign Dependence of the Recovery Time for the 2006 December Forbush Event Measured by the PAMELA Experiment
  • 2018
  • In: Astrophysical Journal. - : Institute of Physics Publishing (IOPP). - 0004-637X .- 1538-4357. ; 853:1
  • Journal article (peer-reviewed)abstract
    • New results on the short-term galactic cosmic-ray (GCR) intensity variation (Forbish decrease) in 2006 December measured by the PAMELA instrument are presented. Forbush decreases are sudden suppressions of the GCR intensities, which are associated with the passage of interplanetary transients such as shocks and interplanetary coronal mass ejections (ICMEs). Most of the past measurements of this phenomenon were carried out with groundbased detectors such as neutron monitors or muon telescopes. These techniques allow only the indirect detection of the overall GCR intensity over an integrated energy range. For the first time, thanks to the unique features of the PAMELA magnetic spectrometer, the Forbush decrease, commencing on 2006 December 14 and following a CME at the Sun on 2006 December 13, was studied in a wide rigidity range (0.4-20 GV) and for different species of GCRs detected directly in space. The daily averaged GCR proton intensity was used to investigate the rigidity dependence of the amplitude and the recovery time of the Forbush decrease. Additionally, for the first time, the temporal variations in the helium and electron intensities during a Forbush decrease were studied. Interestingly, the temporal evolutions of the helium and proton intensities during the Forbush decrease were found to be in good agreement, while the low rigidity electrons (<2 GV) displayed a faster recovery. This difference in the electron recovery is interpreted as a charge sign dependence introduced by drift motions experienced by the GCRs during their propagation through the heliosphere.
  •  
46.
  • Munini, R., et al. (author)
  • Short-term variation in the galactic cosmic ray intensity measured with the PAMELA experiment
  • 2017
  • In: Proceedings of Science. - : Sissa Medialab Srl.
  • Conference paper (peer-reviewed)abstract
    • New results on the galactic cosmic ray (GCR) short-term intensity variation associated with Forbush decrease and co-rotating interaction regions (CIRs) measured by the PAMELA instrument between November 2006 and March 2007 are presented. Most of the past measurements on Forbush decrease events were carried out with neutron monitor detector. This tecnique allows only indirect detection of the overall GCR intensity over an integrated energy range. For the first time, thanks to the unique features of the PAMELA magnetic spectrometer, the Forbush decrease associated with the December 13th coronal mass ejection (CME) was studied in a wide rigidity range (0.4 - 20 GV) and for different species of GCRs detected directly in space. Using GCR protons, the amplitude and the recovery time of the Forbush decrease were studied for ten rigidity interval with a temporal resolution of one day. For comparison the helium and the electron intensity over time were also studied. The temporal evolution of the helium and proton intensity was found in good agreement while the electrons show, on average, a faster recovery time. This was interpreted as a charge-sign dependence introduced by drift motion experienced by the low rigidity (< 5 GV) GCRs during their propagation through the heliosphere. Moreover a clear 13.5 days cyclical variation was observed in the GCR proton intensity after the Forbush decrease. This phenomena could be interpreted as an effect of prominent structures of compressed plasma in the solar wind, i.e. CIRs, or to the latitudinal gradient due to the crossing of the heliospheric current sheet (HCS). 
  •  
47.
  • Panico, B., et al. (author)
  • Cosmic Rays Investigation by the PAMELA experiment
  • 2020
  • In: Journal of Physics. - : IOP Publishing.
  • Conference paper (peer-reviewed)abstract
    • PAMELA (Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics) is a satellite-borne experiment. It was launched on June 15th 2006 from the Baikonur space centre on board the Russian Resurs-DK1 satellite. For about 10 years PAMELA took data, giving a fundamental contribution to the cosmic ray physics. It made high-precision measurements of the charged component of the cosmic radiation challenging the standard model of the mechanisms of production, acceleration and propagation of cosmic rays in the galaxy and in the heliosphere. PAMELA gave results on different topics on a very wide range of energy. Moreover, the long PAMELA life gives the possibility to study the variation of the proton, electron and positron spectra during the last solar minimum. The time dependence of the cosmic-ray proton and helium nuclei from the solar minimum through the following period of solar maximum activity is currently being studied. Low energy particle spectra were accurately measured also for various solar events that occurred during the PAMELA mission. In this paper a review of main PAMELA results will be reported.
  •  
48.
  • Panico, B., et al. (author)
  • Study on CRE arrival distributions with PAMELA experiment
  • 2015
  • In: Proceedings of Science. - : Proceedings of Science (PoS).
  • Conference paper (peer-reviewed)abstract
    • From 2009, several experiments, like PAMELA, FERMI and AMS, have shown a rise in the fraction of positrons versus electrons+positrons. One of the most probable explanation is due to the presence of nearby sources, like SNRs or pulsars. PAMELA (Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics) is a ballooon-borne experiment and is collecting data since 15 June 2006. Its quasi-polar orbit permits to perform a survey in each direction of the sky. The study of the arrival distribution of cosmic ray electrons and positrons from different regions allows the exploration of different origins for the excess.
  •  
49.
  • Panico, B., et al. (author)
  • Time dependence of the helium flux measured by pamela
  • 2017
  • In: Proceedings of Science. - : Sissa Medialab Srl.
  • Conference paper (peer-reviewed)abstract
    • The last solar cycle has presented a peculiarly long quiet phase with consequent minimum modulation conditions for cosmic rays. The proton and electron spectra were measured from July 2006 to December 2009 by PAMELA experiment, providing fundamental information about the transport and modulation of cosmic rays inside the heliosphere. These studies allow to obtain a more complete description of the cosmic radiation. In this picture the time dependence of the helium spectrum become very important to constrain parameters of the actual solar modulation model. The crucial point for this analysis is the selection of a dataset of helium events which ensure high statistics with a very low contamination. In this paper the definition of the selection criteria for helium events with data taken from July 2006 to June 2014 by PAMELA experiment is reported. 
  •  
50.
  • Panico, B., et al. (author)
  • Time dependence of the proton and helium flux measured by PAMELA
  • 2017
  • In: Proceedings of Science. - : Sissa Medialab Srl.
  • Conference paper (peer-reviewed)abstract
    • The energy spectra of galactic cosmic rays carry fundamental information regarding their origin and propagation, but, near Earth, cosmic rays are significantly affected by the solar magnetic field which changes over time. The time dependence of proton and electron spectra were measured from July 2006 to December 2009 by PAMELA experiment, that is a ballooon-borne experiment collecting data since 15 June 2006. These studies allowed to obtain a more complete description of the cosmic radiation, providing fundamental information about the transport and modulation of cosmic rays inside the heliosphere. In this talk the study of the time dependence of the cosmic-ray protons and helium nuclei from the unusual 23rd solar minimum through the following period of solar maximum activity is presented.  
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