Particle Light brightness increase when it is near of another

I have a campfire with a simply particles of fire. This particles have a light component. Up here all right.
I also have a stick that when I aprroach it to the campfire the stick goes on. The particles of the stick are the same of the campfire.
The problem is that when I goes on the stick, the ligh brightness of both, the stick and the campfire, increase, and when I put out the fire of the stick the light of the campfire returns to the normal. I know that the problem is in the light component of the particles because if I disable one, the light brightness not increase.

Is there any way to have the two particle systems with ligh component but that the light does not increase??