x1 is unconscious/not aware of x2 (object/abstract).
This is unconsciousness wrt a specific thing (x2); widen for generalized unconsciousness. This may more or less include (some aspects of) sleep, but sleep is a very specific and complex process, and most forms of unconsciousness do not function in a manner which is even remotely similar to sleep. This is NOT "subconscious" in many meanings or contexts. See also: sipna.