= Escape-speed scaling of wind mass loading
{title2=$\nu\propto v_{\rm esc}^{-2}\text{ or }v_{\rm esc}^{-1}$}
If <stellar feedback> supplies energy $e_*$ per unit formed stellar mass, an <energy-driven outflow> requires $\nu v_{\rm esc}^2/2\lesssim e_*$. Fixed energy coupling therefore suggests <mass-loading factor> $\nu\propto v_{\rm esc}^{-2}$. A fixed momentum supply $p_*$ instead gives $\nu v_{\rm esc}\lesssim p_*$ and <momentum-driven outflow> scaling $\nu\propto v_{\rm esc}^{-1}$. These are launch and escape estimates, not universal wind laws; subsequent entrainment, cooling and fallback change the escaping mass.
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