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Title: Characterization of a Solar Mass Eclipsing Binary with TESS and IGRINS

Stellar radius measurements from eclipsing binaries are typically ∼5% larger than standard stellar models predict. This disagreement means we are unable to derive reliable model-dependent radii, which impact stellar and exoplanet characterization. Using light curves from the TESS satellite and high-resolution, near-infrared spectra from IGRINS, we determine the masses and radii of a main sequence eclipsing binary, V1177 Cen (TIC 3099339). We detrend the light curve using a Gaussian process and derive radial velocities using spectral-line broadening functions, fitting both jointly in an MCMC framework. We find that both stars are near 1Mwith radii 6%–9% larger than the Sun. Based on the absence of Lithium in optical spectra, the inflation is potentially the effect of early post-main sequence evolution, or magnetic fields. We compare our measurement to model isochrones, finding the most consistent agreement with models that include magnetic fields, and correspond to an age of ∼4 Gyr.

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Publication Date:
Journal Name:
Research Notes of the AAS
Page Range or eLocation-ID:
Article No. 196
DOI PREFIX: 10.3847
Sponsoring Org:
National Science Foundation
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