Have a mesh not affect light builds?

I have a mesh that’s just a cylindrical band that has an emissive material that pans around it. In order to get the lighting to look right, I have to have lights floating above them so that there will be a soft golden glow, as if the “holograms” are actually giving off light. However, when I bake lighting, the hologram objects cast these gross golden artifacts on the ground. I am unable to disable “cast shadows” on these objects. The box is checked and greyed out. I was hoping that was the solution to my problem.

Is there a way to get the “cast shadows” button to not be greyed out? Or a way to make the mesh stop casting these artifacts?

This is the hologram with the spot light floating above it, and you can see the ring of artifacting on the floor around it.

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