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New experiments are performed using a gamma ray spectrometer installed at the cosmic ray station in Apatity. The spectrometer monitors the differential spectrum of gamma radiation coming from the atmosphere in the 0.1–4 MeV range of energies. Analysis of the gamma radiation spectra in dozens of increases shows that the effect of growing gamma radiation during precipitation is not related to the presence of radionuclides, or the additional release of radionuclides from the soil. The characteristics of the gamma ray spectra indicate meteorological processes in the atmosphere as the primary cause of the increase effect. [ABSTRACT FROM AUTHOR]

The article considers the production kinetics of vibrationally excited NO(X2Π, > 0) molecules at heights of Earth's middle atmosphere during the precipitation of high-energy protons. The intensity profiles of the luminescence of the infrared bands of nitric oxide at 5.3 and 2.7 μm were calculated for precipitation of high-energy protons into Earth's atmosphere during the events GLE65, GLE67, GLE69, and GLE70 of the 23rd solar cycle. Calculations have shown that the highest integral luminescence intensity values of the 5.3 and 2.7 μm bands were obtained for GLE69: 5.7 and 0.18 kR (kilorayleighs), respectively. Comparison of the calculation results for the 5.3 µm band during the GLE69 event with experimental data obtained from the TIMED spacecraft on January 20, 2005, showed that the calculation results were overestimated by a factor of 2. [ABSTRACT FROM AUTHOR]

Event GLE66 (October 29, 2003) is the least studied of three GLE events that occurred in the fall of 2003. This is because of the powerful magnetic storm and deep Forbush effect against which GLE66 occurred. The emergence of the T-05 storm model of the magnetosphere and the availability of a way of solving the reverse problem applied to dozens of less complex GLE events allow consideration of the event. Values are obtained for the parameters of the cosmic ray flux at subsequent moments in time. A pattern typical of GLE events is observed: the spectrum of observed cosmic rays at the initial phase has an exponential shape, and ends in a power law. The obtained spectra are in good agreement with measurements of cosmic ray precipitation on spacecraft at lower energies. [ABSTRACT FROM AUTHOR]

Results are presented from analyzing the GLE73 event in terms of solar cosmic rays. The GLE73 event raised the count by 2–6% at polar stations of the World Neutron Monitor Network. A direct solution to the inverse problem is found, along with and the energy spectra of solar cosmic rays at the boundary of the magnetosphere are obtained and the pitch angle distribution of the flux. [ABSTRACT FROM AUTHOR]

Based on models of the electronic kinetics of triplet and singlet states of molecular nitrogen and singlet states of molecular oxygen for the Earth's middle atmosphere, we calculated the intensity profiles of the bands of the first and second positive N2 systems, the Lyman–Birge–Hopfield N2 bands, and the infrared O2 bands in the case of precipitation of high-energy protons during the GLE65, GLE67, GLE69, and GLE70 events of solar cycle 23. Calculations have shown that almost over the entire interval of altitudes of 20–80 km, there is a significant contribution from the processes of quenching some electronically excited states of N2 and O2 during molecular collisions. The kinetics of O2 singlet states at the altitudes of the middle atmosphere during proton precipitation is considered taking into account both direct excitation by high-energy particles and intermolecular processes of electron excitation transfer. [ABSTRACT FROM AUTHOR]

A comparative analysis is performed of data on variations in the electromagnetic component over a solar cycle (SC) to study increases in gamma radiation in different phases of an SC. Variations in the intensity of cosmic rays are detected in Apatity by different detectors for all main components of secondary cosmic rays: nucleonic, electron–muonic, and electromagnetic (gamma radiation). [ABSTRACT FROM AUTHOR]

A portable complex for detecting secondary cosmic ray is developed and built for monitoring cosmic rays during expeditions and in remote locations and lighthouses. The complex contains detectors of neutrons, charged particles, and gamma fluxes. It is tested during expeditions in the Barents and Greenland seas. [ABSTRACT FROM AUTHOR]

The intensity profiles of the bands of the first and second positive N2 systems and the infrared atmospheric and atmospheric O2 systems were calculated based on models of the electronic kinetics of triplet states of molecular nitrogen and singlet states of molecular oxygen for the middle Earth's atmosphere in the case of the precipitation of high-energy protons into the Earth's atmosphere during the ground-level enhancement (GLE) (no. 69) on January 20, 2005. Calculations have shown that there is a significant contribution from the quenching of the B3Πg state during molecular collisions over nearly all of the considered altitude range of 20–80 km. The kinetics of O2 singlet states at altitudes of the middle atmosphere during proton precipitation is considered. Both direct excitation by high-energy particles and intermolecular processes of electron-excitation transfer are taken into account. It is shown that the quenching of the state during inelastic molecular collisions leads to a significant decrease in the intensities of the bands of the atmospheric system at the heights of the middle atmosphere. [ABSTRACT FROM AUTHOR]

Results are presented from modeling two different conditions for parameterizing the geometry of Earth's atmosphere and the spectrum of primary cosmic rays. In the first, the input data correspond to solar cosmic rays and calculations are made for all geographic latitudes and longitudes. The second is devoted to estimating the contribution from the nuclei of galactic cosmic rays while considering only a local region of the atmosphere. [ABSTRACT FROM AUTHOR]

Results are presented from the numerical modeling of two independent GLE events that occur at different times and have different energy characteristics of protons in primary particles. The resulting dependences are analyzed with allowance for features caused by characteristics of each spectrum. [ABSTRACT FROM AUTHOR]

Data from most neutron monitor stations show that the intensity of cosmic rays has not yet reached the level observed at them in 2009. At a number of stations (e.g., Barentsburg, Thule, Kerguelen, and Moscow), however, the intensity has already surpassed the 2009 level. This anomalous effect could be associated with the unusual behavior of solar activity in cycle 24. [ABSTRACT FROM AUTHOR]

The cosmic ray laboratory of the Polar Geophysical Institute has created a simple and compact telescope with a modular design that is designed to detect ionizing particles in the energy range from 1 MeV to 100 GeV. The telescope consists of two scintillator plates separated by a layer of lead that are located one above the other. The electronic circuit creates a channel for counting the upper detector and a channel of coincidences with the lower one. The area of each detector is 0.25 m2; the average count rate of the upper detector is 3000 pulses/min. [ABSTRACT FROM AUTHOR]

Descriptions and technical characteristics are given for compact Geiger counters designed to verify calculations of cosmic ray transport through the Earth's atmosphere. Results are presented in the form of a comparison of the altitude profiles of count rates of charged particles, obtained via modeling and field experiments. [ABSTRACT FROM AUTHOR]

The best location for a portable device to monitor cosmic rays is sought. A criterion of selection is the requirement of obtaining new data not duplicated by existing stations. [ABSTRACT FROM AUTHOR]

An electrodynamic model of a solar flare is proposed by I.M. Podgorny that explains its main observed manifestations. Solar cosmic rays are accelerated along a singular line of the magnetic field of a current sheet by an electric field of Fields are found via MHD modeling above the active region in real scale of time, which can only be done using parallel computations. [ABSTRACT FROM AUTHOR]

A special case of modeling the passage of cosmic rays through the Earth's atmosphere is considered for a ground level enhancement event that occurred on January 20, 2005. Altitude profiles of ionization, obtained by calculating the passage of solar protons with energy spectra corresponding to prompt and delayed components, are presented. [ABSTRACT FROM AUTHOR]

An overview is presented of the possibilities of using the module of the RUSCOSMICS software package designed for calculating the passage of cosmic ray (CR) particles through the Earth's atmosphere. General information on current ways of studying secondary CR fluxes is considered. References are made to works by other groups. Key points of the calculation algorithm are described. Parameterization of initial conditions is analyzed. Typical results obtained in modeling are given. A summary of this work and the outlook for the project are given. [ABSTRACT FROM AUTHOR]

The Irkutsk 3 cosmic ray station (Mount Khulugaysha, Eastern Sayans, 3000 m) receives an additional neutron monitor section equipped with a high-speed data acquisition system developed at the Polar Geophysical Institute. It is the first time a high-speed data acquisition system is installed at a high-altitude neutron monitor. Characteristics of multiplicity events at lowland and high-altitude stations are compared to reveal substantial differences between multiplicity events. [ABSTRACT FROM AUTHOR]

Several detectors have been integrated into a single system for monitoring the electromagnetic component of secondary cosmic rays (SCRs) at the Cosmic Ray Laboratory of the Polar Geophysical Institute (Apatity). The system includes a differential gamma-ray spectrum detector based on a NaI(Tl) crystal. One gamma-ray spectrum is collected in 30 min. The energy range is 0.2–8 MeV. It should be noted that like other detectors, the spectrometer was precalibrated using known lines. Background gamma radiation increases during precipitation. More than 1500 such events have been detected since the detector became operational. A number of long-term measurements have been made thus far, which make it possible to study in detail the energy parameters of increase events. The main aim of the study is to compare the characteristics between the spectra in clear weather and under different types of precipitation. Particular attention is given to radiation analysis of samples collected during the rain. The results show there is no pollution of water with radionuclides. It is concluded that the observed effect is due to purely atmospheric effects. A preliminary interpretation of the phenomenon is the creation of a model for the acceleration of charged particles of SCRs in the electromagnetic fields of nonthunderstorm rain clouds. The results from calculations are presented, and their consistency with the experimental data is shown. [ABSTRACT FROM AUTHOR]

The flare source of thermal X-rays above a magnetic arch in the corona arises from the dissipation of the magnetic energy of the current sheet formed at the reconnection of magnetic-field lines. The sources of hard X-rays emitted from the footpoints of the magnetic arch are beams of electrons accelerated in field-aligned currents induced by the Hall electric field generated in the current sheet. Both the hard X-rays detected above the active region and the type III radio emission are radiated by electrons accelerated in the field-aligned currents induced by Alfven waves. The solar cosmic rays are emitted promptly at the instant of the flare. It is important that the Lorentz electric field accelerates protons along the singular magnetic X line. The relativistic protons propagate along the interplanetary magnetic field. These protons have exponential spectra, typical for acceleration occurring in current sheets. A mechanism that is relevant for the generation of delayed cosmic rays, which demonstrate significant anisotropy and a power-law spectrum with γ ∼5, is also discussed. [ABSTRACT FROM AUTHOR]

An Erratum to this paper has been published: https://doi.org/10.3103/S1062873822220014 [ABSTRACT FROM AUTHOR]

Analysis of the relativistic proton spectra of solar flares occurring in the 23rd solar activity cycle derived from data of a worldwide neutron monitor network and numerical modeling both provide evidence for the acceleration of charged particles by an electric field that arises in coronal current sheets during reconnection. The method used to obtain the spectra is based on simulating the response of a neutron monitor to an anisotropic flux of relativistic solar protons with specified parameters and determining the characteristics of the primary relativistic solar protons by fitting model responses to the observations. Studies of the dynamics of the energy spectra distinguish two populations of relativistic protons in solar cosmic-ray events: the so-called fast component, which arrives at the flux front of the solar cosmic rays, followed by the delayed slow component. The fast component is characterized by strong anisotropy and an exponential energy spectrum, in agreement with the spectrum yielded by mathematical modeling of particle acceleration by an electric field directed along the X line of the magnetic field. The slow component, whose propagation is probably diffusive, has a power-law spectrum.© 2005 Pleiades Publishing, Inc. [ABSTRACT FROM AUTHOR]