Posterior distribution from the thermal-relic WDM fit to DES and PS1 MW satellites, presented in Nadler et al. (2021), cast into the parameter space of our self-interacting sterile-neutrino DM model (i.e., m ₄, ﹩{\sin }^{2}2\theta ﹩, and λ _ϕ ). Dark (light) shaded contours represent 68% (95%) confidence intervals, respectively. Marginalized posteriors are shown in the top panel of each column. Note that σ _M , σ _gal, and ﹩{\sigma }_{\mathrm{log}R}﹩ are reported in dex, ﹩{{ \mathcal M }}_{50}﹩ is reported as ﹩{\mathrm{log}}_{10}({{ \mathcal M }}_{50}/{{ \mathcal M }}_{\odot })﹩, m ₄ is reported as ﹩{\mathrm{log}}_{10}({m}_{4}/\mathrm{keV})﹩, ﹩{ \mathcal A }﹩ is reported in pc, and α, ﹩{ \mathcal B }﹩, n, ﹩{\sin }^{2}2\theta ﹩, and λ _ϕ are dimensionless. For details on the prior distributions assumed for galaxy–halo connection parameters when forward-modeling the MW satellite population, see Nadler et al. (2021).