The values for two-parametric variations spectra are determined for the whole period of observations in 1957-2017 years. A long-period changes of spectra with taking into account of cut-off rigidity changes are presented.

Determining transport coefficients for galactic cosmic ray (GCR) propagation in the turbulent interplanetary magnetic field (IMF) poses a fundamental challenge in modeling cosmic ray modulation processes. GCR scattering in the solar wind involves wave-particle interaction, the waves being Alfven waves which propagate along the ambient field (B). Empirical values at 1AU are determined for the components of the diffusion tensor for GCR propagation in the heliosphere using neutron monitor (NM) data. At high rigidities, particle density gradients and mean free paths at 1AU in B can only be computed from the solar diurnal anisotropy (SDA) represented by a vector A (components A(r), A, and A) in a heliospherical polar coordinate system. Long-term changes in SDA components of NMs (with long track record and the median rigidity of response R(m)20GV) are used to compute yearly values of the transport coefficients for 1963-2013. We confirm the previously reported result that the product of the parallel (to B) mean free path ((||)) and radial density gradient (G(r)) computed from NM data exhibits a weak Schwabe cycle (11y) but strong Hale magnetic cycle (22y) dependence. Its value is most depressed in solar activity minima for positive (p) polarity intervals (solar magnetic field in the Northern Hemisphere points outward from the Sun) when GCRs drift from the polar regions toward the helioequatorial plane and out along the heliospheric current sheet (HCS), setting up a symmetric gradient G(s) pointing away from HCS. G(r) drives all SDA components and (||)G(r) contributes to the diffusive component (A(d)) of the ecliptic plane anisotropy (A). GCR transport is commonly discussed in terms of an isotropic hard sphere scattering (also known as billiard-ball scattering) in the solar wind plasma. We use it with a flat HCS model and the Ahluwalia-Dorman master equations to compute the coefficients (=/(vertical bar)) and (a measure of turbulence in the solar wind) and transport parameters (||), , G(r), G(s), and an asymmetric gradient G(a) normal to the ecliptic plane. We study their dependence on rigidity (R), p/n intervals, sunspot numbers (SSNs), and solar wind parameters at 1AU. (||) exhibits a strong 22y dependence but G(r) does not, explaining solar polarity dependence of (||)G(r). The computed G(r) values are an order of magnitude greater than those reported by our colleagues making an ad hoc assumption that is low (0.01). At high rigidities, the drift contribution at 1AU is small and unsteady. A new methodology is outlined to compute yearly GCR north-south anisotropy (A) from the data for a single detector sorted for p/n intervals. We show that G(a) is the main contributor to A in the steady state, and G(a) is shown not correlated with the north-south excess SSNs.

Galactic cosmic rays and solar energetic particles with sufficient rigidity to penetrate the geomagnetic field, enter the Earth's atmosphere and interact with the electrons and the nuclei of its atoms and molecules. From the interactions with the nuclei, cascades of secondary particles are produced that can be detected by ground-based detectors such as neutron monitors and muon counters. The theoretical study of the details of the atmospheric showers is of great importance, since many applications, such as the dosimetry for the aviation crews, are based on it. In this work, a new application which can be used in order to study the showers of the secondary particles in the atmosphere is presented. This application is based on the Monte Carlo simulation techniques, performed by using the well-known Geant4 toolkit. We present a thorough analysis of the simulation's critical points, including a description of the procedure applied in order to model the atmosphere and the geomagnetic field. Representative results obtained by the application are presented and future plans for the project are discussed. (C) 2014 Elsevier B.V. All rights reserved.

As many great discoveries, the phenomenon of cosmic rays was discovered mainly accidentally, during investigations that sought to answer another question: what are sources of air ionization? This problem became interesting for science about 230years ago in the end of the 18th century, when physics met with a problem of leakage of electrical charge from very good isolated bodies. We describe the history how step by step cosmic rays was discovered and why this phenomenon received misnomer, how in cosmic rays was discovered the first antiparticle – positron. These discoveries were recognized among greatest in the 20th Century and were awarded by Nobel Prize.

A short history of the beginning of cosmic ray (CR) astrophysics is considered: from the hypothesis on CR origin as a result of Supernova explosions in the Metagalaxy, to a model of solar origin of CR, galactic origin based on the stochastic mechanism of charged particle acceleration in interstellar space, to extragalactic and hierarchical models of CR origin, as well as galactic CR origin taking into account radio-astronomical data. We consider also the first balloon results on the chemical contents of primary CR (especially of the contents Li, Be, B), important for any model of CR origin. Investigations of the injection problem, CR drift and diffusion acceleration by shock waves, and CR generation in Supernova remnants were also important steps in the beginning of CR astrophysics.

The neutron monitors are the ground based detectors that continuously measure the flow of the cosmic rays that reach the earth′s surface. The measurements of the neutron monitors are of great importance for the scientific community since they contribute to the study of several scientific fields, such as the solar activity and the prediction of the space weather. For this reason, most of the neutron monitors worldwide are organized in a network, in order for their measurements to be easily accessible. The correct evaluation of the measurements and their connection with the physical quantities of the cosmic rays require the knowledge of the interactions and the detection procedure that take place inside the neutron monitor. In this work a quantitative study of the 6NM-64 behavior is presented based on Monte Carlo simulations by using the well known Geant4 simulations toolkit. The study focuses on the detection efficiency of the neutron monitor, both in sections and as a whole for the different particle species, on its dependence on the incident direction of the particles and on the secondary neutrons produced inside the neutron monitor.

We consider possible effects of cosmic rays and some other space factors on the Earth's climate change. It is well known that the system of internal and external factors formatting the climate is very unstable; decreasing planetary temperature leads to an increase of snow surface, and decrease of the total solar energy input into the system decreases the planetary temperature even more, etc. From this it follows that even energetically small factors may have a big influence on climate change. In our opinion, the most important of these factors are cosmic rays and cosmic dust through their influence on clouds, and thus, on climate.

Intense geomagnetically induced currents (GIC) can hamper rail traffic by disturbing signaling and train control systems. GIC threats have been a concern for technological systems at high-latitude locations due to geomagnetic disturbances driven by substorm expansion electrojet or convection electrojet intensifications. However, other geomagnetic storm processes such as storm sudden commencement (SSC) and geomagnetic pulsations can also cause GIC concerns for technological systems. We present in this paper the first evidence based on statistical data for links between geomagnetic disturbances and faulty operations (anomalies) in the functioning of railway automatics and telemetry. We analyze anomalies of automatic signaling and train control equipment which occurred in 2004 on the East-Siberian Railway (corrected geomagnetic latitude ϕm=46–51°N and longitude λm=168–187°E). Our results reveal a seasonal effect in the number of anomalies per train similar to the one observed in geomagnetic activity (Kp, Ap, Dst indices). We also found an increase by a factor of 3 in the total duration of daily anomalies during intense geomagnetic storms (local geomagnetic index specific to Siberian Observatory Amax>30), with a significant correlation between the daily sum of durations of anomalies with geomagnetic activity. Special attention was paid to failures not related to recognized technical malfunctions. We found that the probability of these failures occurring in geomagnetically disturbed periods was 5–7 times higher than the average anomaly occurrence.

Abstract: It is well known that energy spectrum of solar energetic particles (SEP), observed by ground based neutron monitors and muon telescopes (in high energy region; the transfer to the space from the ground observations is made by the method of coupling functions, see in Chapter 3 of [1]), and by detectors on satellites and space-probes (in small energy region) changed with time very much (usually from very hard at the beginning of event to very soft at the end of event). The observed spectrum of SEP and its change with time are determined by three main parameters: energy spectrum in source, time of ejection, and propagation mode. In the past we considered the first step for forecasting of radiation hazard: the simple isotropic mode of SEP propagation in the interplanetary space (see Chapter 2 in [2]). It was shown that on the basis of observation data at several moments of time could be solved the inverse problem and determined energy spectrum in source, time of ejection, and diffusion coefficient in dependence of energy and distance from the Sun. Here we consider the inverse problem for the complicated case: mode of anisotropic diffusion and kinetic approach. We show that in this case also the inverse problem can be solved, but it needs NM data at least at several locations on the Earth. We show that in this case the solution of inverse problem starts to work well sufficiently earlier than solution for isotropic diffusion, but after 20-25 minutes both solutions give about the same results. It is important that obtained results and reality of used model can be controlled by independent data on SEP energy spectrum in other moments of time (does not used at solving of inverse problem). On the basis of obtained results can be estimate the total release energy in the SEP event and radiation environment in the inner Heliosphere, in the magnetosphere, and atmosphere of the Earth during SEP event.