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Particle Monitor
There is also a Particle Monitor (PM) monitoring environmental particle fluxes; this is useful for preventing damages of the PhotoMultipliers (PMTs) viewing the dectectors: actually, when the measured particle flux exceeds a settable threshold, it switches off the high voltage supplies of all the PMTS, except for its own PMT. When the flux decreases below the threshold again, it restores the PMTs' situation.

Figure: A Sketch of the PDS and of its electronics (from [Frontera et al. 1997a]).
\begin{figure}\begin{center} \epsfig{file=pds_sketch.ps, width=13.0cm, angle=270}\end{center}\end{figure}


Cristiano Guidorzi 2003-07-31