Overview showing the plasma and magnetic field data for a unique ICME event observed in June 1980 measured with Helios 1 at 0.53 au (DOY171–173; see also Burlaga et al. 1982; Bothmer & Schwenn 1998). From top to bottom we present the parameter’s plasma-beta, proton temperature (in red we give the expected solar wind temperature ×0.5, as described in Richardson & Cane 1995), total magnetic field strength, vector components of the magnetic field, proton density, and proton bulk speed. The four identified density structures are marked, with the shock arrival discontinuity followed by the sheath region (blue shaded area) ahead of the density enhancement of the so-called LE (yellow shaded area) ahead of the ME body (green shaded area). It should be noted that the green labeled interval matches well with a bidirectional flow of suprathermal electrons covering the period of 20 June, 02–21 UT (see Fig. 6 in Bothmer 1999).