We present a continuation of an analysis that aims to quantify resolution of
N-body simulations by exploiting large (up to N=40963) simulations of
scale-free cosmologies run using Abacus. Here we focus on radial pairwise
velocities of the matter field, both by direct estimation and through the
cumulative-2PCF (using the pair conservation equation). We find that
convergence at the 1% level of the mean relative pairwise velocity can be
demonstrated over a range of scales, evolving from a few times the grid spacing
at early times to slightly below this scale at late times. We show the analysis
of two different box sizes as well as from averaging results from the smaller
boxes, and compare the power of the two aforementioned estimators in
constraining accuracy at each scale. Down to scales of order of the smoothing
parameter, convergence is obtained at ∼5% precision, and shows a
behaviour indicating asymptotic stable clustering. We also infer for LCDM
simulations conservative estimates on the evolution of the lower cut-off to
resolution (at 1% and 5% precision) as a function of redshift.Comment: 14 pages, 9 figures, 1 table. Accepted for publication in MNRAS. v2
does NOT overlap with arXiv:2308.0043