Radius inflation means that a star’s measured radius is larger than what stellar structure models predict for its given mass, temperature, and age.
In metal rich stars, Higher metallicity can affect stellar structure and energy transport, potentially leading to inflated radii.The increased opacity impedes the efficient outward flow of energy generated in the core. The trapped energy and resulting thermal gradient can alter the star's internal structure and slow the rate of convective heat transport, causing the outer layers to increase compared to a metal-poor star.
Researchers used TESS-Gaia Light Curves. It continuously measures stellar brightness with high precision. The ePoint Spread Function method accurately separates the target star’s light from nearby stars in TESS images.
They determine the Orbital Period by eclipse bisector method, a geometric technique that finds the exact midpoint of the eclipse.
They used the cross-correlation method (CCF) in code. It is used in spectroscopy to measure the radial velocity (RV) of a star. It compares the observed stellar spectrum (may be Doppler-shifted) with a template spectrum (a reference of known velocity) to find how much the wavelengths are shifted.
Here PHOEBE modeling code is used that combines light and velocity data. Orbital period (P) determined from light curve minima. Mass ratio from RV amplitude, Temperature ratio determined from spectral flux ratio and light curve shape, Semimajor axis via Kepler’s 3rd law.
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