Average values of the changes in ω, e and θ for S2 over one orbital period (~16 yr) in the N-body integrations. Filled circles are from integrations with m = 50 M_⊙ and open circles are for m = 10 M_⊙; the number of field stars was N = { 25,50,100,200 }  for both values of m. The abscissa is the distributed mass within S2’s apobothron, at r ≈ 9.4 mpc. In each frame, the points are median values from the 100 N-body integrations, and the error bars extend from the 20th to the 80th percentile of the distribution. a) Changes in the argument of peribothron. The contribution from relativity, Eq. (7), has been subtracted. The solid line is Eq. (11). b) Changes in the eccentricity. Solid and dashed lines are Eq. (14), with m = 50 M_⊙ and m = 10 M_⊙ respectively and with K_e = 1.4. c) The angle between initial and final values of L for S2. Solid and dashed lines are Eq. (15) with K_t = 1.0.