Shape of Cerenkov Radiation Signal in FPD Cells

I have been looking at Cerenkov photons in Geant 4, 

It seems that the Cerenkov photons are distributed with a narrower shower shape than that of the deposited energy. 

If the  most forward part of the angular distribution of  Cerenkov  photons is overrepresented in the detected signal, the effect can be greater.

This can increase the fraction of the photon signal in the high tower from 78%(deposited energy) to as high as 90% for an incident photon aimed at the center of the cell.

For Scintillation photons, the shower shape is very similar to the deposited energy distribution, however, it may be that scintillation is a small part in the observed signal from these FPD or the Small Cell FMS detectors.