The Forbush-decreases in cosmic ray fluxes and solar-proton events in July and September 2017

Abstract

The study of the nature of variations in cosmic ray fluxes, including diurnal, 27-day, annual, etc., and the question of the relationship of solar-geophysical factors on the state of the atmosphere attracts special attention of scientists. Coronal mass ejections are the result of solar winds generated on the Sun during a series of flares. At the same time, solar winds provoke variations in the intensity of cosmic rays, which include, in particular, Forbush-decreases. The article presents brief characteristics of the CARPET detector of the scientific cosmophysical complex of the L.N.Gumilyov ENU and experimental data obtained at this facility during the observation of Forbush-deacreases in July and September 2017. The results of the analysis of variations in cosmic ray fluxes are presented and their relationship with the conditions in the interplanetary medium and the Earth’s magnetosphere caused by processes on the Sun is described. It was found that the decrease in cosmic ray fluxes in July and September 2017 was due to high solar activity (a series of solar flares). A comparative analysis of the time changes recorded by the CARPET detector modules of the L.N.Gumilyov ENU scientific complex with the data of the world network of neutron monitors («Apatity», «Almaty» and «Jungfraujoch IGY») is also presented. Data on the electromagnetic environment of interplanetary space during the period of heliospheric and magnetospheric disturbances were also used for the analysis. The analysis showed that the measurement data of the CARPET detector is in good agreement with the data of the above-mentioned neutron monitors of the world network, which allows us to study the physical nature of cosmic ray variations for different time intervals.