Robust asteroseismic properties of the bright planet host HD 38529

TL;DR

This study detects and analyzes solar-like oscillations in the bright star HD 38529 using TESS data, providing precise stellar properties and demonstrating the effectiveness of shorter timeseries for asteroseismology.

Contribution

The paper presents the first asteroseismic analysis of HD 38529 using TESS data, yielding robust stellar parameters and showcasing the potential of short-cadence observations.

Findings

Confirmed stellar mass near 1.48 solar masses

Derived stellar radius of approximately 2.68 solar radii

Estimated stellar age around 3.07 billion years

Abstract

The Transiting Exoplanet Survey Satellite (TESS) is recording short-cadence, high duty-cycle timeseries across most of the sky, which presents the opportunity to detect and study oscillations in interesting stars, in particular planet hosts. We have detected and analysed solar-like oscillations in the bright G4 subgiant HD 38529, which hosts an inner, roughly Jupiter-mass planet on a 14.3 d orbit and an outer, low-mass brown dwarf on a 2136 d orbit. We combine results from multiple stellar modelling teams to produce robust asteroseismic estimates of the star's properties, including its mass $M = 1.48 \pm 0.04 \mathrm{M}_\odot$, radius $R = 2.68 \pm 0.03 \mathrm{R}_\odot$ and age $t = 3.07 \pm 0.39 \,\mathrm{Gyr}$. Our results confirm that HD 38529 has a mass near the higher end of the range that can be found in the literature and also demonstrate that precise stellar properties can be measured given shorter timeseries than produced by CoRoT, Kepler or K2.