Proc. IAU volume 13, issue S335, P82-86 2017 DOI: 10.1017/s1743921317010122 View full text
Pauli Väisänen, Ilya Usoskin, Kalevi Mursula

Abstract: AbstractFluxes of galactic cosmic rays (GCR) observed at 1 AU are modulated inside the heliosphere at different time scales. Here we study the properties of the power spectral density (PSD) of galactic cosmic ray variability using hourly data from 31 neutron monitors (NM) from 1953 to 2016. We pay particular attention to the reliability of the used datasets and methods. We present the overall PSD and discuss different parts of the spectrum and the related periodicities. We find significant spectral peaks at th…

expand abstract