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

Francesco Bollati , Giuseppe Lodato , Daniel J. Price , Christophe Pinte (1)

1 IPAG - Institut de Planétologie et d'Astrophysique de Grenoble

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

Keywords: methods: analytical; planets and satellites: detection; planet-disc interactions; protoplanetary discs; Astrophysics - Earth and Planetary Astrophysics

Domains: Sciences of the Universe [physics]

Francesco Bollati, Giuseppe Lodato, Daniel J. Price, Christophe Pinte. The theory of kinks - I. A semi-analytic model of velocity perturbations due to planet-disc interaction. Monthly Notices of the Royal Astronomical Society, 2021, 504, pp.5444-5454. ⟨10.1093/mnras/stab1145⟩. ⟨insu-03705292⟩