its estimated uncertainty.

In the second observation, we noted additional artifacts in the sky image resembling a rabbit-ear antenna extending $20^{\prime\prime}$ from the pulsar in orthogonal directions along the detector axes with point-like sources at the ends. Temporal analysis of the region showed that the rabbit-ear counts occurred during a number of specific time intervals lasting tens of seconds. Examination of the mission timeline parameters showed that the occurrence of these events always followed the “AOFF\_GAP” times by a few hundred seconds. Furthermore, data drop-outs were found for tens of seconds at the “AOFF\_GAP” times and during the following intervals when the spurious counts were recorded. We wrote an algorithm to generate a new good-time-intervals file which eliminates these intervals based on the “AOFF\_GAP” times.

Two additional detector issues needed consideration when extracting accurate timing information: telemetry saturation and a hardware time-stamp mis-assignment. Although data obtained during the first observation displayed nominal background levels, the second observation was plagued by intervals of telemetry saturation induced by high background levels; such occurrences can seriously affect timing studies by introducing spurious periods in the power spectrum aliased with the full buffer rate of $\sim 4$ ms. We filtered out telemetry-saturated time intervals 