  This paper studies size-polydisperse Lennard-Jones systems described by
active Ornstein-Uhlenbeck particle dynamics. The focus is on the existence of
isomorphs (curves of invariant structure and dynamics) in the model's
three-dimensional phase diagram. Isomorphs are traced out from a single
steady-state configuration by means of the configurational-temperature method.
Good invariance of the reduced-unit radial distribution function and the
mean-square displacement as a function of time is demonstrated for three
uniform-distribution polydispersities, 12%, 23%, and 29%. Comparing to
active-matter isomorphs generated by the analytical direct-isomorph-check
method, the latter give somewhat poorer invariance of the structure, but better
invariance of the dynamics. We conclude that both methods can be used to
quickly get an overview of the phase diagram of polydisperse AOUP models
involving a potential-energy function obeying the hidden-scale-invariance
property required for isomorph theory to apply.
