What will the opposite of $this->be() is in a Laravel unit test?

I'm have a test case with different assertions on it, one of them is for testing the unauthorized access, so I'm trying to log out the user that i previously authenticated with $this->be($user), I need to log out the user, not change the way I'm doing the tests, so I just need something to revert $this->be(), but I can't find it.