arr_x_am241_200_20_030702_107:

tanx: -0.620
tany: -0.089

3728 (11.3%) leading edge detectors
7536 (23.0%) trailing edge detectors
11264 (34.4%) total edge detectors

counts/s/fully illuminated detector/channel

black: center detectors included
blue: center + trailing edge detectors included
red: all detectors included


blue: fractional difference between using center detectors and using center + trailing edge detectors
red: fractional difference between using center detectors and using all detectors

The blue curve gives the fractional excess when trailing edge detectors are included. Any excess seen in this curve isn't due to photons incident on leading edge detectors, but rather is most likely due to scattered events. If we can assume that all edge detectors are equally likely to measure such scattered events, we would expect the red curve to show a greater excess simply because more edge detectors are included. Since there are 7536 trailing edge detectors in this case and a total of 11264 edge detectors in all, we would expect the excess to be higher by about a factor of 11264/7536 (1.5) due to these scattered events alone. We actually see a a good deal more than this, especially at the lowest channels (around channels 40-50). So including leading edge detectors does appear to affect the spectrum in the tails by as much as 5-10% in some channels.

cg24_x_ba133_030304_26:

tanx: -0.670
tany: -0.490

5888 (18.0%) leading edge detectors
5376 (16.4%) trailing edge detectors
11264 (34.4%) total edge detectors

counts/s/fully illuminated detector/channel

black: center detectors included
blue: center + trailing edge detectors included
red: all detectors included


blue: fractional difference between using center detectors and using center + trailing edge detectors
red: fractional difference between using center detectors and using all detectors

Due to the greater number of edge detectors alone, the red curve is expected to have have 2.1 times the excess that the blue curve has. The excess is actually greater than this.

arr_x_cd109_200_21_030630_72:

tanx: 0.682
tany: -0.007

2768 (8.4%) leading edge detectors
8496 (25.9%) trailing edge detectors
11264 (34.4%) total edge detectors

counts/s/fully illuminated detector/channel

black: center detectors included
blue: center + trailing edge detectors included
red: all detectors included


blue: fractional difference between using center detectors and using center + trailing edge detectors
red: fractional difference between using center detectors and using all detectors

Due to the greater number of edge detectors alone, the red curve is expected to have have 1.3 times the excess that the blue curve has. The excess is actually greater than this.

arr_x_co57_200_20_030619_9a:

tanx: -0.043
tany: 0.597

4880 (14.9%) leading edge detectors
6384 (19.5%) traiing edge detectors
11264 (34.4%) total edge detectors

counts/s/fully illuminated detector/channel

black: center detectors included
blue: center + trailing edge detectors included
red: all detectors included


blue: fractional difference between using center detectors and using center + trailing edge detectors
red: fractional difference between using center detectors and using all detectors

Due to the greater number of edge detectors alone, the red curve is expected to have have 1.76 times the excess that the blue curve has. It is hard to tell because of the statistical noise, but it appears that in the higher tail at least, the excess is greater than this.

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