How do I hide Area Light Diffuse?

[cammerz]

I have created an animation in SolidEdge ST7 as my company does not currently own the animation license for KeyShot 5.0. A section of the animation is for a part to fade to 0% after a period of 4 seconds. When I render this in KeyShot I can clearly see the part fading away, however when I have an area light diffuse applied to the part, to simulate a glowing orange heat source, during and after the part has faded it is still emitting the light diffuse. Is there a way for me to fade out the diffuse emission with the part?