Command State 93266-94064

The above diagrams represent the P/E, RNG, and PEN logic in the "P1 singles" mode. The equations for P/E, RNG, and PEN events are:

Event type	Coincidence equation
P, E	P1
RNG	P1.P4.AL*
PEN	P1.P8

(The P3* term was also deleted from the PLO and ELO equations, but since events are checked against the rate equations for the *HI before the *LO scalers, events with and without P3 triggers will still be sorted properly.) The buffers into which "orderly" events can fall are as follows:

Range	No guards triggered	Low, not high guard triggered	High guard triggered
P1	P/E	P/E	P/E
P1 through P2	P/E	P/E	P/E
P1 through P3	P/E	P/E	P/E
P1 through P4, P5, P6, or P7	P/E, RNG	P/E	P/E
P1 through P8	P/E, RNG, PEN	P/E, PEN	P/E, PEN

There is a lot of ambiguity for longer-range events (P4 or deeper detectors triggered); however, since the rate equations are checked for PEN, then RNG, then the P and E rates, RNG and PEN events with no guard-triggers should still be counted in the correct rates. Nevertheless, the problem with guard events, where a penetrating event with guard triggers will be counted in the PEN rate alongside those with no guard triggers but will then fail to qualify for PHA telemetry output, is still in place. Also, because of the removal of the requirement that at least P1 and P2 be triggered in order for an event to enter the PHA queue, the rates went up so high that I have never convinced myself that I could sort out spurious coincidences properly.

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new 6 August 1999