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The Experimental Spectrum of Variations of Cosmic Rays in a Wide Range of Hardness According to AMS-02 Data


All reliable information on the long-term characteristics of the interplanetary medium, such as the spectrum of variations and the anisotropy and gradients of cosmic rays, have been obtained from the data of a ground-based network of detectors since its inception. However, to solve the inverse problem, it was required to know the shape of the spectrum of variations, which until now was only given empirically. In this work, we have studied and experimentally determined the spectrum of variations of protons and helium nuclei based on precision measurements of particle fluxes up to a hardness of 60 GV outside the atmosphere on an AMS-02 magnetic spectrometer, in addition to establishing the transformation of the form of this spectrum when the polarity of the solar magnetic field is reversed. The found form of the spectrum of cosmic-ray variations will allow increasing the accuracy of the reconstructed parameters of the spectrum of variations and will form a solid basis for further studies of modulation effects in the heliosphere and related applications.

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This work was performed using the equipment of the Russian National Ground-Based Network of Cosmic-Ray Stations.

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Correspondence to V. G. Yanke.

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Yanke, V.G., Belov, A.V., Shlyk, N.S. et al. The Experimental Spectrum of Variations of Cosmic Rays in a Wide Range of Hardness According to AMS-02 Data. Cosmic Res 59, 427–432 (2021).

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