"Operation and performance of the NESTOR test detector" Nucl.Instr ...

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G. Aggouras et al. / Nuclear Instruments and Methods in Physics Research A 552 (2005) 420–439 433
Fig. 11. The total number of accumulated photoelectrons inside the trigger window during bioluminescence activity (crosses) and with
no bioluminescence (histogram).
Fig. 12. Trigger rates as a function of the coincidence level, for
two threshold settings. The points represent the data, the solid
line the Monte Carlo estimation including background and the
dashed line the Monte Carlo estimation for the contribution of
the atmospheric muons.
At the end of the active experimental window
there is a small peak in the data that does not
appear in the Monte Carlo expectation. This is due
to a known malfunction in the first generation of
ATWDs, which digitize a low amplitude ghost
Fig. 13. Total number of photoelectrons inside the coincidence
window as a function of the coincidence level for two threshold
settings. The points represent the data and the histogram gives
the Monte Carlo estimation. The errors are calculated from
event statistics and not from the number of the photoelectrons.
The number of photoelectrons is the mean number collected
inside the coincidence window per trigger.
pulse at the end of their active window. This
problem does not affect the analysis because only
pulses inside the trigger window are used.