Score Window. A time-bounded, disposable counter used to evaluate whether observed events have crossed a detection threshold.
A score window belongs in the Acceleration Plane. It can make a detection decision fast, but it must not become the durable record of what happened, why enforcement occurred, or what state should be restored after failure. If losing a score window corrupts truth, the system has turned detection acceleration into a hidden source of record.
The threshold rule says what counts and what follows; the score window is only the disposable working state used to evaluate that rule quickly.