Abstract

We present the results on variations of ion spectra in the energy range from 1 keV to 3 MeV. The spectra measured onboard the INTERBALL Tail Probe satellite on November 13, 1995, during the satellite's passage from the dipole field lines to the lines stretched into the magnetotail are analyzed. The data of the CORALL, DOK-2, and SKA-2 instruments are used to reconstruct the ion spectra. It is shown that, when the ion spectrum along the satellite trajectory is averaged over 2-min intervals, it is smooth up to geocentric distances of 6R E. With decreasing distances, the form of the particle spectra in the region under consideration remained virtually unchanged (region from L = 11R E down to L= 6R E) and only insignificant variations of the energy of the spectral maxima are observed. Possible reasons for the observed regularities are discussed.