How do Limb-Darkening curves differ at two different wavelengths?

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TL;DR

Wavelengths of lets say 4000 Angstroms and 7000 angstroms.

Does the limb-darkening curve fall off faster at shorter wavelengths or at longer wavelengths?

 

[phinds]

Summary:: Wavelengths of let's say 4000 Angstroms and 7000 angstroms.

Does the limb-darkening curve fall off faster at shorter wavelengths or at longer wavelengths?

What research have you done on this? What have you found out?