Temporal variations of the interplanetary magnetic field at the Earth's orbit and of the solar activity

This paper analyzes the time changes of the common oscillations of the spectra of the absolute value of the interplanetary magnetic field measured at the Earth's orbit from 1964 to 1997 and of solar activity (the Wolf sunspot numbers). The frequency components of the spectra were determined using the method of non-linear spectral analysis. Oscillations with common periods of T = 10.8, T = 8.8, and T = 3.73 years have been identified in the long-period part of the spectra, and their temporal variations are shown. We discuss the specific features of the spectral band in the short-period part of the spectra in the vicinity of the known periods of T similar to 1.3 years and T similar to 150 days that have been identified earlier in the solar data and in the solar wind parameters.