INTERBALL-1 observations of plasma and energetic particle fluxes upstream of the Earthʹs bow shock

In this paper, we follow our recent statistical examinations of solar wind plasma fluctuations in the Earthʹs foreshock and their relationship to measurements of energetic ion ( ∼ 25 keV) fluxes under different solar wind and interplanetary magnetic field conditions, based on the INTERBALL-1 data obtained during 1995–2000. We study in detail the influence of more energetic particles ( ∼ 50 and 110 keV energy channels) and their energetic and angular distributions. We compare the intervals of upstream observations outside the foreshock and inside the foreshock of different strengths and relate plasma fluctuations to observed energetic particle spectra and anisotropy at different distances to the bow shock. We discuss possible physical explanations of observed phenomena.