Research Information System
TESS Science Conference II (TSC2), 02 August 2021
Kepler asteroseismology has played an important role in the
characterization of host stars and their planetary systems. Target
selection biases, however, meant that this synergy would remain mostly
confined to main-sequence stars. The advent of TESS has since lifted
this restriction, enabling the systematic search for transiting planets
around seismic giants, as well as revisiting previously known evolved
hosts using asteroseismology. Here, we present the detailed
asteroseismic modeling of two high-luminosity red-giant branch hosts,
KOI-3886 and iota Draconis. KOI-3886, observed by Kepler over 4 years
and later by TESS over 1 sector, has been a longtime candidate host.
iota Draconis, observed by TESS over 5 sectors, is known to host a
planet in a highly eccentric orbit. The precise (~ 6%) seismic mass
derived for iota Draconis was combined with new radial-velocity
observations to detect an additional long-period companion. Regarding
KOI-3886, asteroseismology was key in helping reveal the planet
candidate as a false positive and reinterpreting the system as an
eclipsing brown dwarf in a hierarchical triple with two evolved stars.
This brings to light the importance of asteroseismology in the study of
planetary orbital dynamics off the main sequence and its lesser known
role in candidate vetting.