Among the most fundamental properties of a dark matter halo is its density profile. Motivated by the recent proposal by García et al. [Mon. Not. R. Astron. Soc. 521, 2464 (2023)] to define a dynamical halo as the collection of orbiting particles in a gravitationally bound structure, we characterize the mean and scatter of the orbiting profile of dynamical halos as a function of their orbiting mass. We demonstrate that the orbiting profile of individual halos at fixed mass depends on a single dynamical variable, the halo radius $r_{\mathrm{h}}$, which characterizes the spatial extent of the profile. The scatter in halo radius at fixed orbiting mass is $\approx 16\%$. Only a small fraction of this scatter arises due to differences in halo formation time, with late-forming halos being more compact (smaller halo radii). Accounting for this additional correlation results in an $\approx 11\%$ scatter in halo radius at fixed mass and halo formation time.

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• Cosmology
• Dark matter
• Large scale structure of the Universe
• Massive compact halo objects