Improve TESS light-curve modeling for J2236 beyond current PHOEBE fit

Develop a light-curve modeling approach that achieves a better fit to the TESS light curve of the eclipsing binary Gaia DR3 2002164086682203904 (J2236; AK Lac) than the PHOEBE model, by reducing or eliminating the large, correlated residuals identified by the authors.

Background

The authors jointly fit ASAS-SN and TESS light curves with radial velocities using PHOEBE. For J2236 (AK Lac), they note the presence of large, correlated residuals in the TESS light-curve fit, potentially linked to systematic effects in the detrending or other modeling limitations.

Despite exploring modeling options, they report being unable to find a better PHOEBE solution for the TESS data of this target, highlighting an unresolved modeling challenge specific to this system.

References

There are large, correlated residuals in the TESS light curve model of J2236, but we are unable to find a better solution with PHOEBE.

— Precise and Accurate Mass and Radius Measurements of Fifteen Galactic Red Giants in Detached Eclipsing Binaries  (2409.02983 - Rowan et al., 2024) in Section 5.8: J2236: GDR3 2002164086682203904