rayleigh corrected reflectance in ICOR

Hello all!

I´m working with OLI and MSI in order to test different kinds of atmospheric correction. I understand that ICOR (In SNAP interface) returns the rhos (surface reflectance) at different wavelengths. But, also I need to work with the rhot (reflectance at the top of the atmosphere) and rhorc (rayleigh corrected reflectance). Does anyone can help me to get them?