Detectability of substellar companions around white dwarfs with Gaia

TL;DR

This paper explores Gaia's potential to detect substellar companions around white dwarfs, providing preliminary simulation results on the likelihood of discovering such planets and brown dwarfs in wide orbits.

Contribution

It presents the first simulation-based assessment of Gaia's capability to detect white dwarf planetary companions, highlighting expected detection rates and orbital configurations.

Findings

Gaia can potentially detect tens of white dwarf planets and brown dwarfs.

Simulations suggest a gap in orbital periods due to stellar evolution effects.

Preliminary results indicate promising detection prospects for wide-orbit companions.

Abstract

To date not a single-bona fide planet has been identified orbiting a single white dwarf. In fact we are ignorant about the final configuration of >95% of planetary systems. Theoretical models predict a gap in the final distribution of orbital periods, due to the opposite effects of stellar mass loss (planets pushed outwards) and tidal interactions (planets pushed inwards) during the RGB and the AGB stellar expansions. Over its five year primary mission, Gaia is expected to astrometrically detect the first (few tens of) WD massive planets/BDs giving first evidence that WD planets exist, at least those in wide orbits. In this article we present preliminary results of our simulations of what Gaia should be able to find in this field.