Fig. 6

Ion phase space density for the 24-s period from 16:37:51 to 16:38:15 UT in the unit of \(\textrm{s}^3 \textrm{m}^{-6}\). a The two-dimensional slice of the ion phase space density, showing the anti-sunward beam component. The plane includes the spin axis (close to the GSE Z direction), Sector 14 (close to the anti-sunward direction) with the peak of the phase space density and Sector 6 (opposite to Sector 14; close to the sunward direction). b The ion phase space density at Elevation 3 which is directed \(22.5^{\circ }\) southward of the GSE XY plane and includes the peak of the anti-sunward beam component. c The one-dimensional cut of the ion phase space density in the direction of the anti-sunward beam component (Sector 14 and Elevation 3). (See Mukai et al. (1994) for the details of the LEP-EAi instrument.) Ion phase space density taken in the lobe/mantle region from 16:36:03 to 16:36:15 UT is shown in Panels d–f in the same format as above. The colour scales for the phase space density in 6 panels are identical. Logarithmic is presented on the right side