Cumulative Event Distributions

Next: Marginal Distributions Up: The Effects of Event Previous: Radial Surface Brightness Profiles

Cumulative Event Distributions

Pileup effects are seen also in the cumulative radial distribution of counts (i.e. the encircled energy). In Figure 14 we show the outward migration of EER(70%) and EER(90%) for these tests. For example, EER(70%) increases from 2.4 pixels for a fluence of 0.29 cpf to 3.1 pixels for a fluence of 5.6 cpf. This effect is again due to central event losses. Similar effects are seen in marginal distributions shown in Figure 15.

**Table 3:** Pileup data for the four cases shown in Figures 13, 14, 15, and 16.
Image name	Pileup fraction	Counts per frame
H-IAI-CR-1.001	0.08	0.29
H-IAI-CR-1.003	0.25	0.93
H-IAI-CR-1.005	0.53	2.98
H-IAI-CR-1.007	0.59	5.60

**Figure 14:** Encircled energy plots for the four pileup cases shown in Figure 13.

Alexandria Ware
1999-03-29