Stellar radial migration
= Stellar radial migration
A change in a star's mean orbital radius through exchange of <angular momentum>, particularly at a <corotation resonance> with a rotating perturbation. For the $k_R=0$ harmonic in <action-angle variables>, the leading change of <radial action> vanishes even while azimuthal <angular momentum> changes. Migration can therefore rearrange a <galactic disk> with much less heating than exchange at a <Lindblad resonance>.