posted on 02.04.2020, 08:59by Rebecca Nealon, Nicolas Cuello, Richard Alexander
We now have several observational examples of misaligned broken protoplanetary discs, where
the disc inner regions are strongly misaligned with respect to the outer disc. Current models
suggest that this disc structure can be generated with an internal misaligned companion (stellar
or planetary), but the occurrence rate of these currently unobserved companions remains
unknown. Here we explore whether a strong misalignment between the inner and outer disc
can be formed without such a companion. We consider a disc that has an existing gap –
essentially separating the disc into two regions – and use a flyby to disturb the discs, leading
to a misalignment. Despite considering the most optimistic parameters for this scenario,
we find maximum misalignments between the inner and outer disc of ∼45◦ and that these
misalignments are short-lived. We thus conclude that the currently observed misaligned discs
must harbour internal, misaligned companions.
NC acknowledges financial support provided by FONDECYT grant 3170680 and from CONICYT project Basal AFB-170002. This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 823823 (DUSTBUSTERS). This project has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement No 681601). This work was performed using the DiRAC Data Intensive service at Leicester, operated by the University of Leicester IT Services, which forms part of the STFC DiRAC HPC Facility (www.dirac.ac.uk). The equipment was funded by BEIS capital funding via STFC capital grants ST/K000373/1 and ST/R002363/1 and STFC DiRAC Operations grant ST/R001014/1. DiRAC is part of the National e-Infrastructure.
Monthly Notices of the Royal Astronomical Society, Volume 491, Issue 3, January 2020, Pages 4108–4115, https://doi.org/10.1093/mnras/stz3186