1GeV photons in TOF
In this study 1GeV +/- 0.1 GeV were generated between 1 and 11 degree polar angle and from 0 to 360 degree in phi.
The number of hits per plane as a function of paddle number is shown below for both TOF planes:
At this point no low energy threshold cut is applied. In the following the energy distribution of these hits is shown as
seen on both ends of the paddle. Again for both planes where the first plot shows the more upstream TOF plane.
The black histogram is the left/up PMT the red histogram is the right/down PMT. The plots show paddle 12 to 27 in
each plane. What can easily be identified is the second peak in the second TOF plane originating from the second lepton
that is generated in the conversion of the high energy photon. This second peak is at double the energy of the first prominent
peak seen in both planes.