Physics.Arcade.Body#checkCollision

Set the checkCollision properties to control which directions collision is processed for this Body.
For example checkCollision.up = false means it won't collide when the collision happened while moving up.
If you need to disable a Body entirely, use body.enable = false, this will also disable motion.
If you need to disable just collision and/or overlap checks, but retain motion, set checkCollision.none = true. An object containing allowed collision.