This page shows the two visible ways a detector event can fail the trigger gate. A candidate on a masked channel has candidate-enabled bit 0, and an otherwise enabled candidate with veto bit 1 is also rejected. The ledger is exact for the stated bits, while real vetoes and masks must account for noisy channels, timing mismatches, changing detector status, calibration, and uncertainty.
Either a masked channel or a veto bit rejects the event. Exact arithmetic here means exact results for the stated model inputs; measured inputs still carry uncertainty and significant-figure limits.
highlighted = computed this step
A masked candidate cannot pass
A candidate on a masked channel has candidate-enabled bit 0.
A=0×(1−0)=0
A veto rejects an otherwise enabled candidate
An enabled candidate with veto bit 1 has accepted bit 0.