Collision
Sets attributes on and/or groups particles when they collide with geometry.
The default setting is bounce on collision, which causes particles to bounce off the surface of an object. However, the behavior can be modified in the operation controls toolbar or in the parameter editor to die, stop, stick, or slide on collision. You can also set the behavior to continue on course, which makes the particles pass through the object. This tool is useful for defining how particles should react when they collide with objects.
Using Collision
Click the
Collision button on the Drive Particles tab.Click
the 
particle system you want to be affected and press Enter to confirm your selection.Click
the object you want the particles to affect and press Enter to confirm your selection.Choose how the particles will react in the Behavior drop-down menu on the operation controls toolbar or in the parameter editor.
For specific parameter help see the Collision node help.