A series of scintillation events produce responses from the PMTs in an Anger camera. The recorded pulses have a photopeak centered at pulse height 180. The pulse height is proportional to the energy deposited into the crystal, which is shown in Figure P8.3(a). (This is not a pulse height spectrum.)

Figure P8.3 See Problem 8.9

(a) We want to set an acceptance window around the photopeak to reject those the photons that have undergone Compton scattering angles larger than 50 degrees. What is the range of photon energies that will be accepted by the acceptance window?

Consider seven PMTs located around the origin of the x-y coordinates on the face of the Anger camera shown in Figure P8.3(b). The diameter of the tubes is 2 mm and each tube has been assigned a number. A single scintillation event yields a response from the PMTs. All other tubes recorded zero height except these 7 tubes, which recorded heights 40, 5, 15, 15, 20, 45, 30 in the order of tube numbers.

(b) Compute the Z-pulse. Will this pulse be accepted by the acceptance window?

(c) Estimate the position of the event (X,Y).

(d) Explain why we do not set (X,Y) equal to the location of the PMT having the largest amplitude.