(a) Solar wind bulk speed in the upstream of the termination shock. This is in fact the same data as the solar wind speed at 90 AU shown in Fig. 2b, repeated for convenience. (b) Compression ratio R defined by Eq. (10). (c) Cutoff energy of filled-shell distribution defined by Eq. (9). (d) Temperature of reflected PUI distribution defined by Eq. (7). (e) PUI density ratio relative to total ion density in the inner heliosheath, that is, $\chi =\frac{n_{\mathrm{PUI}}}{(n_{\mathrm{PUI}}+n_{\mathrm{SW}})}$.