The theory of kinks – I. A semi-analytic model of velocity perturbations due to planet–disc interaction

A new technique to detect protoplanets is by observing the kinematics of surrounding gas. Gravitational perturbations from a planet produce peculiar `kinks' in channel maps different gas species. In this paper, we show that such kinks can be reproduced using semi-analytic models for velocity perturbation induced planet. doing so i) confirm observed are consistent with planet-induced wake; ii) how quantify mass kink amplitude; particular, amplitude scales square root channels far velocity, steepening linear as approach planet; iii) extend theory include effect damping, which may needed order have localized kinks.