New Asteroseismic Constraints on Transiting Planet Systems Observed by TESS

Despite the hundreds of thousands of asteroseismic detections from TESS, very few asteroseismic detections of planet host stars have been made. However, additional data from the extended missions of TESS has made the detection of smaller transiting planets and solar-like asteroseismic signals easier. Here, we report the detection of TOI-7041 b, a hot Jupiter orbiting a red giant star. Our asteroseismic analysis indicates that TOI-7041 has a mass of 1.07±0.07 M⊙ and a radius of 4.10 ± 0.11 R⊙, making it one of the largest stars around which a transiting planet has been discovered with the Transiting Exoplanet Survey Satellite (TESS), and the mission's first oscillating red giant with a transiting planet. TOI-7041 b has an orbital period of 9.691±0.006 days and a low eccentricity of e = 0.04 ± 0.04. We measure a planet radius of 1.02 ± 0.03 RJup with TESS photometry, and a planet mass of 0.36±0.16 MJup (114±51 M⊕) with ground-based radial velocity measurements. TOI-7041 b appears less inflated than similar systems receiving equivalent incident flux, and its circular orbit indicates that it is not undergoing tidal heating due to circularization. The asteroseismic analysis of the host star provides some of the tightest constraints on the stellar properties of a TESS planet host and enables precise characterization of the hot Saturn. We also present two new asteroseismic constraints in two other previously confirmed systems, TOI-2669 and TOI-4551, further improving constraints on planet masses and radii and thus testing theories of planet (re-)inflation. These asteroseismic detections of planet hosts indicate that extended TESS observations of evolved stars will similarly provide a path to improved exoplanet characterization.