Variation of the number of observed encounters per unit perihelion distance as a function of perihelion distance (for the filtered sample for all t_ph). The open circles count the encountering stars discretely, using as the distance estimate for each star. The filled circles count each surrogate for each encountering star separately. The green line is the distribution we expect under the assumption that the distribution is linear. It has a gradient of 50.0 pc⁻¹. (The number of encounters within some distance is the integral of this, i.e. ∝ .) The data do not follow this near to the limit (at 10 pc) because not all stars found in the LMA-based selection actually come within 10 pc after doing the orbital integration. The error bars show the Poisson noise computed from the theoretical relation (only attached to the open points to avoid crowding).