The expected performance in terms of sensitivity is summarised in
Fig. 1. This is the performance we expect for the second
phase of the project in which high quantum efficiency hybrid photo sensors will replace
the
photo-multipliers of the telescope's camera. In the first phase our threshold
will be GeV, in the second phase 10 GeV. It is not yet clear
how soon the second phase will follow the first. The sensitivity at energies
> 30 GeV is to a good approximation independent of these changes.
Given the diverse shape of GRB light-curves it is difficult to predict an average
counting rate for gamma-rays in successful burst observations. We note instead that
the MAGIC Telescope will have an effective collection area for primary gamma photons
of 108 cm2 at the threshold rising to 109 cm2 at 100 GeV.
For a hypothetical counting rate of 0.1Hz for EGRET above 100 MeV, we expect
(assuming a spectral index of 2.0) a counting rate of Hz above 10 GeV.
A rate of
Hz for 30 s will suffice for a 5
detection with
a moderate background rejection applied. For strong bursts such as GRB 930131,
gamma counting rates of the order of 1 kHz may occur. The data acquisition will
therefore be prepared to sustain such rates without additional dead-time.
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