RUSCOSMIC — the new software toolbox for detailed analysis of cosmic ray interactions with matter

At present, cosmic ray (CR) physics uses a considerable variety of methods for studying CR char-acteristics of both primary and secondary fluxes. Experimental methods make the main contribution, using various types of detectors, but numerical methods increasingly complement it due to the active development in computer technology. This approach provides researchers with the most extensive infor-mation about details of the process or phenomenon and allows us to make the most competent conclu-sions. This paper presents a concept of the RUSCOSMIC © software package based on the GEANT4 toolkit and representing a range of different numerical models for studying CR propagation through medium of different systems (radiation detectors, Earth’s atmosphere). The obtained results represent response functions of the main radiation detectors as well as some typical characteristics of secondary CR fluxes. Comparative results also show the operation of the module verification of calculations with experimental data

New narrow-beam neutron spectrometer in complex monitoring system

In the interaction of cosmic rays (CRs) with Earth’s atmosphere, neutrons are formed in a wide range of energies: from thermal (E≈0.025 eV) to ultrarelativistic (E>1 GeV). To detect and study CRs, Polar Geophysical Institute (PGI) uses a complex monitoring system containing detectors of various configurations. The standard neutron monitor (NM) 18-NM-64 is sensitive to neutrons with energies E>50 MeV. The lead-free section of the neutron monitor (BSRM) detects neutrons with energies E≈(0.1÷1) MeV. Also, for sharing with standard detectors, the Apatity NM station has developed and installed a neutron spectrometer with three energy channels and a particle reception angle of 15 degrees. The configuration of the device makes it possible to study the degree of anisotropy of the particle flux from different directions. We have obtained characteristics of the detector (response function and particle reception angle), as well as geometric dimensions through numerical simulation using the GEANT4 toolkit [Agostinelli et al., 2003]. During operation of the device, we collected database of observations and received preliminary results

Nature of gamma radiation variations during atmospheric precipitation

The Polar Geophysical Institute has developed a complex facility for continuously monitoring various components of secondary cosmic rays. Gamma radiation during precipitation events has been found to increase the year round regardless of the season. A series of experiments has revealed that there is no precipitation pollution by any natural or artificial radionuclides. Radiation spectrum does not have any characteristic lines of elements. We propose a mechanism providing a satisfactory description for this phenomenon