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In this work, a new analysis of the isotopic composition of boron nuclei (B) in galactic cosmic rays (GCRs) in the range of rigidities of 1–5 GV (nuclear energies 0.1–1.5 GeV/nucleon) was carried out using data from the PAMELA space experiment 2006–2014 on the rigidity of detected nuclei and their velocity (time-of-flight analysis and ionization losses in the instrument's multilayer calorimeter). The new results of the PAMELA experiment expand the energy range of previous measurements, are consistent with the few existing data, and indicate deviations of the B isotope ratios from the GALPROP simulation data for the GCR, similar to the deviations for the Li and Be isotopes in the PAMELA data, which can be interpreted as evidence of observation against the background of the GCR of the contribution of several local sources from explosions of nearby (hundreds of parsecs) supernovae. [ABSTRACT FROM AUTHOR]

The isotopic composition of Li and Be nuclei in the 1–5 GV range of rigidities (nuclear energies of 0.1–1.5 GeV/nucleon) is analyzed using PAMELA flight data from 2006–2014 on the rigidity of detected nuclei and their velocities (time-of-flight analysis and ionization losses in the detector's multilayer calorimeter). The new PAMELA data expand the range of energies in earlier measurements, are consistent with scarce results, and indicate correlated deviations of Li and Be isotope ratios from the GALPROP data for GCRs, which can be interpreted as evidence of contributions from several nearby local sources against the GCR background. Analysis of precision AMS-02 data on the spectra of positrons, antiprotons, and secondary nuclei of Li, Be, and B also indicates correlated increases in intensity at rigidities of ~50–1000 GV, which could also be due to local sources. The contribution from local sources against the GCR background is estimated at levels of tens of percents for rigidities of 1–5 GV and several percent at rigidities of 50–1000 GV. [ABSTRACT FROM AUTHOR]

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 70° 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 2°. 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. [ABSTRACT FROM AUTHOR]

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 He counters and a moderator with an area of 0.18 m 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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Large-scale anisotropy or so-called sidereal-diurnal wave has been detected in the PAMELA satellite experiment in the time interval of 2006-2014. The magnitude of anisotropy has been measured simultaneously for the Southern and Northern Hemispheres in the equatorial coordinate system. The results confirm the data of ground-based experiments. [ABSTRACT FROM AUTHOR]

The available data on the energy spectra of electrons, protons, and helium nuclei in the high-energy region are fragmentary, a situation made worse by their scarcity. Due to limitations imposed on the use of the magnetic spectrometer in the PAMELA satellite experiment, the calorimeter must be used for measurements performed in the high-energy region. The processing of experimental data accumulated in more than eight years of measurements with the calorimeter, neutron detector, and scintillation counters allows the spectra of high-energy particles to be obtained, greatly expanding our understanding of the nature of primary cosmic rays. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The development of the GAMMA-400 γ-ray telescope continues. The GAMMA-400 is designed to measure fluxes of γ-rays and the electron-positron cosmic-ray component possibly associated with annihilation or decay of dark matter particles; and to search for and study in detail discrete γ-ray sources, to measure the energy spectra of Galactic and extragalactic diffuse γ-rays, and to study γ-ray bursts and γ-rays from the active Sun. The energy range for measuring γ-rays and electrons (positrons) is from 100 MeV to 3000 GeV. For 100-GeV γ-rays, the γ-ray telescope has an angular resolution of ∼0.01°, an energy resolution of ∼1%, and a proton rejection factor of ∼5 × 10. The GAMMA-400 will be installed onboard the Russian Space Observatory. [ABSTRACT FROM AUTHOR]

A change in the ratio of the intensities of particles of high-energy cosmic rays arriving from the North and South in the time interval of 2010-2014 has been detected with a calorimeter entering into the experimental complex of the PAMELA satellite experiment since June 2006. The polarity of the magnetic field of the Sun changed in a part of this time interval. Thus, the results indicate that the North-South asymmetry of cosmic ray fluxes is related to the magnetic field of the Sun. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

New measurements of the energy spectra of cosmic-ray protons and helium nuclei with significantly increased statistics owing to an improvement of the event selection technique and the involvement of all data over the period 2006-2013 in the analysis have been made at energies above 0.8 TeV/nucleon with a position-sensitive calorimeter based on data from the PAMELA satellite-borne experiment. [ABSTRACT FROM AUTHOR]

The GAMMA-400 gamma-ray telescope currently under development is designed to measure fluxes of gamma rays and electron-positron cosmic-ray components, which could be associated with the annihilation or decay of dark matter particles, and to survey in detail the celestial sphere in order to search for and investigate discrete gamma-ray sources; to measure the energy spectra of Galactic and extragalactic dif- fuse gamma-ray emissions; and to study gamma-ray bursts and the gamma-ray emissions of active Sun. The GAMMA-400 energy range is 100 MeV to 3000 GeV. The gamma-ray telescope has an angular resolution of ∼0.01°, an energy resolution of ∼1%, and a proton rejection factor of ∼10 6. The GAMMA-400 will be installed on Russia’s Navigator space platform. Observations are planned to commence in 2018. [ABSTRACT FROM AUTHOR]

The satellite-borne PAMELA experiment studies cosmic ray spectra over a wide range of energies. The instrument was placed in orbit in June 2006 and remains there to the present day. A position-sensitive calorimeter is one of the main parts of the PAMELA instrument. The calorimeter data are used to determine the energy of particles that interact within it, separate the electron component of the detected radiation from the nuclear component, and reconstruct the tracks of particles passing through the instrument. The special calorimeter and S 4 scintillation shower detector triggers enables us to expand our statistics considerably. Using the calorimeter data in generating these triggers means we can study the anisotropy of cosmic rays with energies in excess of tens of GeV. This method of anisotropy detection is based on reconstructing the direction of a particle’s arrival from the axis of the secondary particle cascade in the calorimeter. [ABSTRACT FROM AUTHOR]

The north-south asymmetry for cosmic-ray particles was measured with one instrument of the PAMELA satellite-borne experiment in the period June 2006–May 2009. The analysis has been performed by two independent methods: by comparing the count rates in regions with identical geomagnetic conditions and by comparing the experimental distribution of particle directions with the simulated distribution that would be in the case of an isotropic particle flux. The dependences of the asymmetry on energy release in the PAMELA calorimeter and on time have been constructed. The asymmetry ( Nn − Ns)/( Nn + Ns) is 0.06 ± 0.004 at the threshold energy release in the calorimeter and gradually decreases with increasing energy release. The observed effect is shown to be produced by electrons in the energy range 10–100 GeV. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The explanation of the observed baryon asymmetry, i.e., the almost complete absence of antimatter in the visible part of the universe, is one of the most important problems in cosmology. The real asymmetry value can be determined by direct measurements of the fluxes of antinuclei with charges | Z| ⩾ 2 in primary cosmic rays near the Earth. The results of the search for antihelium using data from the PAMELA experiment obtained from June 2006 to December 2009 are presented. No events with a charge of −2 have been detected in the rigidity range of 0.6-600 GV. An upper limit on the antihelium/helium flux ratio $\\overline {He} /He$ has been presented as a function of the energy. An integral upper level of 4.7 × 10 is the lowest limit at rigidities above 14 GV. [ABSTRACT FROM AUTHOR]

The PAMELA magnetic spectrometer onboard the Resurs DK1 satellite no. 1 was put into (Earth) orbit on June 15, 2006; measurements continue at the present time. The scientific objective of the spectrometer is the study of antiproton, proton, positron, electron and light nucleus fluxes in cosmic rays. In this paper, we present the technique for measuring electron and positron spectra in the energy range from 20 to 800 GeV. [ABSTRACT FROM AUTHOR]

The trackingsystem for the PAMELA spectrometer is actually under construction usingdouble-sided double metal AC coupled microstrip silicon sensors. To study the performances of the silicon detectors and of the readout electronics several tests have been performed, usingminimum ionizingparticles. The characteristics of the detectors are described and the main results obtained from the July '97 test-beam are presented, with particular reference to the spatial resolution. [ABSTRACT FROM AUTHOR]

The PAMELA experiment is being conducted aboard the Russian satellite Resurs-DK 1, which was launched into a near-Earth circumpolar orbit on June 15, 2006. The instrument, which includes a magnetic spectrometer and an electromagnetic calorimeter (16 X0), allows us to measure the fluxes of cosmic-ray electrons and positrons over a wide range of energies from ∼100 MeV to hundreds of GeV. This work presents the measurement data collected from July 2006 through January 2010 on the spectra of primary cosmic-ray electrons and positrons. At low energies, this spectrum is in good agreement with a diffusion model that includes reacceleration and damping. At high energies, the measured spectrum is harder than the one predicted. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Secondary electron and positron fluxes in the energy range from 3 MeV to 7 GeV were measured with the ARINA and PAMELA spectrometers onboard the Resurs-DK satellite launched on June 15, 2006 into an elliptical orbit with an inclination of 70.4° and an altitude of 350–600 km. It is shown that positrons dominate over electrons by a factor of up to 4–5 in the geomagnetic equator region ( L < 1.2 and B > 0.25). [ABSTRACT FROM AUTHOR]