Some Helios 2 3D-spectra
A new reduction of the 3D raw data. In the following spectra we present
some proton velocity distribution functions as isocountour
plots of phase space density. These 11 spectra correspond to a small
part of the high data mode measurements of the instrument each 40.5 seconds.
For each spectrum we plot the 1D counts distribution, the pitch angle
mictrostructure (two bottom pictures) and a central cut (top-right), in
which the magnetic field is perpendicular to screen plane. Some fluid
parameters are also shown. Tha last three cuts are planes in the velocity
space from the full 3D spectrum. For more details of these representationn
of the velocity distribution functions see: Astudillo, H. F., S.
Livi, E. Marsch, and H. Rosenbauer, Evidence for nongyrotropic alpha particles
and proton distributions functions: TAUS solar wind meassurements, J. Geophys.
Res., 101, 24 423, 1996.