Expected number of stars undergoing a close encounter with β Pic (within 2 pc) as a function of the minimum encounter probability threshold. Top: entire time interval studied (~3.5 Myr). Bottom: most complete portion of the dataset, within the interval ± 0.5 Myr. The orange lines mark the 95% probability threshold adopted±in this work. At this threshold, the expected number of encounters is 49 over 3.5 Myr and 30 in the ±0.5 Myr interval. The red line indicates the independent estimate obtained from the stellar-density-based calculation, yielding 46 encounters in the ±0.5 Myr interval. The total number of expected encounters from our data – corresponding to a 0% probability threshold – is 117 for the full sample and 42 for the ±0.5 Myr interval.