Selective collision with particles I have two collision objects and two particle systems.
I want P1 to interact with collision 1
       P2 to interact with collision 2
Can you help me to achieve that ? 

Now both are interacting with collision 1 :(  

One will collide with it. One should pass through it.
How can
See [Collision Collection] value on Deflection Panel of the Particle information as indicated by the arrows above.  The outliner window shows how the [collection] is visible.  This is how you restrict influence between particles and a Physics Collision object.

The collision object needs to be placed in the collection specified in the particle system.

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