Can complex T Tauri star light curves be modelled with star-spots?

'Transiting Exoplanet Survey Satellite' photometry of 10 young stars with very complex periodic light curves is considered. Previous findings that these cannot be due to dark surface spots are re-evaluated by allowing arbitrarily shaped areas on the stellar surface to have sub-photospheric fluxes. This is done by approximating flux integrals by sums over surface elements. The unknown ratios of spot to photospheric fluxes are determined by lasso or ridge regression procedures. It is found that almost all light curves can be modelled very accurately in this way. The usual, if rarely stated, caveat applies - star-spot models presented in the paper are not unique.

Automated summary

The photometry of 10 young stars from the 'Transiting Exoplanet Survey Satellite' with complex periodic light curves was considered. It was found that almost all light curves can be accurately modeled by re-evaluating the ratios of spot to photospheric fluxes, although the caveat that these models are not unique applies.