Development of a Liquid Scintillator and of Data ... - Borexino - Infn

4 Position Reconstruction of Scintillation Events
scintillator volume, but deposit a fraction of their energy in the scintillator. Monte Carlo simulations
of these background events yield their ‘center of light’ position, which then has to be
folded with the estimated energy resolution to give a meaningful prediction.
For BOREXINO the behaviour is very similar to the CTF (see fig. 4.10). The position resolution
for the pointlike beta events is a little bit better than in the CTF, due to the higher photoelectron
yield ( pe/MeV for BOREXINO, pe/MeV for the CTF). The larger detector
size however gives rise to a bigger time spread due to scattering and absorption/reemission
processes. The energy dependence of the spatial resolution is
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Figure 4.10: Energy dependence of the position resolution for beta and gamma events starting
from the center of the BOREXINO Inner Vessel.