Page History

...

Just to confirm the suspicions, the sparsest event, event 634, was looked at separately. The V1 and square peak finders found only 545 and 584 peaks, respectively. It can be seen in the energy distribution of the peaks for event 634 that the high energy shoulder is still present so it cannot be due to multiple photon complications. Furthermore, by manually checking peaks, it can be seen that the high energy peaks do not neighbor other peaks and are merely just higher energy peaks.

One possible explanation is how the peaks are chosen. For the square peak finder, since the 2x2 region with the highest energy is chosen to complete the square for 1 and 2 pixel photons, it is possible that this includes noise that is higher than average thus shifting the total energy above the mean. Likewise for the V1 peak finder, large noise has a greater chance of being included since it may surpass the lower threshold again shifting the total energy of the peak above the mean.

Pixel Size Effect on Energy

...