  We study the detection of electrons undergoing coherent transfer via
adiabatic passage (CTAP) in a triple quantum-dot system with a quantum
point-contact sensing the change of the middle dot. In the ideal scenario, the
protocol amounts to perfect change transfer between the external dots with
vanishing occupation of the central dot at all times, rendering the measurement
and its backaction moot. Nevertheless, even with minor corrections to the
protocol, a small population builds up in the central dot. We study the
measurement backaction by a Bayesian formalism simulation of an instantaneous
detection at the time of maximal occupancy of the dot. We show that the
interplay between the measurement backaction and the non-adiabatic dynamics
induce a change of the success probability of the protocol, which
quantitatively agrees with a continuous detection treatment. We introduce a
correlated measurement signal to certify the non-occupancy of the central dot
for a successful CTAP protocol, which, in the weak measurement limit, confirms
a vanishing occupation of the central dot. Our proposed correlated-signal
purports that proper experimental method by which to confirm CTAP.
