On 31 January 2016, the flux of >2 MeV electrons observed by Geostationary Operational Environmental Satellite (GOES)‐13 dropped to the background level during a minor storm main phase (−48 nT). ...Then, a second storm (−53 nT) occurred on 2 February; during the 3 days after its main phase, the flux remained at background level. Using data from various instruments on the GOES, Polar Operational Environmental Satellites (POES), Radiation Belt Storm Probes (RBSP), Meteor‐M2, and Fengyun‐series spacecraft, we study this long‐term dropout of MeV electrons during two sequential storms of similar magnitude under lightly disturbed solar wind conditions. Observations from low‐altitude satellites show that the fluxes decreased first at higher L‐shells and then gradually propagated inward. Moreover, the fluxes were almost completely lost and dropped to the background level at L > 5, while the fluxes at 4 < L < 5 were partly lost, as observed by RBSP and low‐altitude satellites. Finally, observations show that on 5 February, only the fluxes at L > 5.5 recovered, while the fluxes at 4 < L < 5 did not return to the prestorm levels. These observations indicate that the loss and recovery processes developed first at higher L‐shells. Phase space density (PSD) analysis shows that radial outward diffusion was the main reason for the dropout at higher L‐shells. Regarding electron enhancement, stronger inward diffusion was accompanied by ultra‐low‐frequency (ULF) wave activities at higher L‐shells, and chorus waves observed at outer L‐shells provided conditions for relativistic electron flux recovery to the prestorm levels.
Key Points
A 5‐day dropout of relativistic electrons occurred during two sequential geomagnetic storms
Slow outward diffusion was responsible for relativistic electron partial loss at 4 < L < 5 and complete loss at L > 5
Flux recovery started at higher L prior to that at lower L due to ULF and chorus waves
The final results of processing the data from the balloon-born experiment ATIC-2 (Antarctica, 2002–2003) for the energy spectra of protons and He, C, O, Ne, Mg, Si, and Fe nuclei, the spectrum of all ...particles, and the mean logarithm of atomic weight of primary cosmic rays as a function of energy are presented. The final results are based on improvement of the methods used earlier, in particular, considerably increased resolution of the charge spectrum. The preliminary conclusions on the significant difference in the spectra of protons and helium nuclei (the proton spectrum is steeper) and the non-power character of the spectra of protons and heavier nuclei (flattening of carbon spectrum at energies above 10 TeV) are confirmed. A complex structure of the energy dependence of the mean logarithm of atomic weight is found.
Abstract
This article presents the early results of synchronous multiwavelength observations of one of the brightest gamma-ray bursts (GRBs) GRB 160625B with the detailed continuous fast optical ...photometry of its optical counterpart obtained by MASTER and with hard X-ray and gamma-ray emission, obtained by the Lomonosov and Konus-Wind spacecraft. The detailed photometry led us to detect the quasi-periodical emission components in the intrinsic optical emission. As a result of our analysis of synchronous multiwavelength observations, we propose a three-stage collapse scenario for this long and bright GRB. We suggest that quasiperiodic fluctuations may be associated with forced precession of a self-gravitating rapidly rotating superdense body (spinar), whose evolution is determined by a powerful magnetic field. The spinar’s mass allows it to collapse into a black hole at the end of evolution.
The K-EUSO project developed in the JEM-EUSO collaboration for installation on board the International Space Station is described. A number of technological projects are successfully executed during ...its preparation: the EUSO-Balloon and EUSO-SPB1 balloon experiments, and the telescope as part of the Telescope Array (EUSO-TA). Since 2019, a wide-angle detector “UV atmosphere” (Mini-EUSO) has been operating on board the ISS Russian Segment. After K-EUSO, it is planned to conduct the even more ambitious POEMMA (Probe of Extreme Multi-Messenger Astrophysics) experiment to register both ultra-high energy cosmic rays (UHECR) and high-energy neutrinos.
The propagation of cosmic ray particles in the atmosphere is modeled and altitude profiles are calculated for radiation dose rates behind aluminum shielding of different thicknesses. Results could ...serve as the basis for a system for monitoring radiation exposure during flights of aircraft.
This paper shows the results of economic regionalization and zoning of the Republic of Tatarstan, conducted in 2017. The latest experience of economic regionalization and zoning of the Republic of ...Tatarstan in 2007 - 2015 is exposed. The economic regionalization problem is solved on the basis of new method and algorithm that uses quantitative measures which characterize spatial and economic features of generated economic regions including their internal and average connectivity, homogeneity, compactness, socio-economic development level and life quality of the population. Three nodal and one homogeneous economic region in the Republic of Tatarstan were identified. The results of economic zoning within homogeneous economic region led to the conclusion about two existing economic zones. They have the potential for developing new economic growth pole and three economic centers - growth points with specialization on agro-industrial sector.
The light emitting diode structure based on
p
-GaN film/
n
-ZnO microdisks quasiarray heterojunction was fabricated. It is shown that the epitaxial quality of
p
-GaN films upon growth from the vapor ...phase can lead to growth of the hexagonal microdisk ZnO rather than the vertical nanorods. The density of the microdisks changed across the substrate surface. ZnO hexagonal microdisks are characterized by the average height of about 5 μm with diameters ranging from 25 μm up to 60 μm. The turn-on voltage of the heterojunction of ZnO/GaN (disks/film) is around 5 V. The diode-ideality factor was estimated to be of around 30. The large values of the ideality factors indicate a high density of trap states and also may be connected with the quality of the contacts to the
p
–
n
junction. The electroluminescence (EL) spectrum acquired from the
p
-GaN film/
n
-ZnO microdisks junction exhibited the bands with maxima at 366, 394 and 495 nm. On the basis of the data of X-ray diffraction, electrical and optical studies these peaks were associated with GaN near-band-edge (NBE) emission, ZnO NBE emission, and emission from the defect levels in ZnO, respectively.
Tunka-133: Results of 3 year operation Prosin, V.V.; Berezhnev, S.F.; Budnev, N.M. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
08/2014, Letnik:
756
Journal Article
Recenzirano
Odprti dostop
The EAS Cherenkov light array Tunka-133, with ~3km2 geometric area, is taking data since 2009. The array permits a detailed study of cosmic ray energy spectrum and mass composition in the PeV energy ...range. After a short description of the methods of EAS parameter reconstruction, we present the all-particle energy spectrum and results of studying CR composition, based on 3 seasons of array operation. In the last part of the paper, we discuss possible interpretations of the obtained results.
This paper presents data on the simultaneous and complementary observations of the gamma-ray burst (GRB) GRB 161017A for optical, X-ray, and gamma wavelengths obtained by the Russian multi-messenger ...Lomonosov space observatory and supplemented by additional data from the Swift satellite as well as the ground-based MASTER Global Robotic Net and the 10 m Gran Telescopio Canarias. Multifrequency spectra of this very powerful explosion indicate that it originated at a distance of 10 billion light years from Earth. Here, we present the results of the prompt, early, and afterglow optical observations. The light curves and spectra suggest that the prompt optical and high-energy emissions occur in the same region near the GRB source.
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