The aesthetic experience is generally considered to be an event or object that produces an experience not necessarily positive, but one that still produces an exciting, enlightening, or even a transcendental effect. One necessary element is the figurative meaning of the object or event that allows it to stand for something else in a set of tropes, such as metaphor, metonym, among others. This encoded communication between artist and audience elevates the experience of the piece to something more than (and also less than) "real." In order for the maximum aesthetic effect to be possible, it helps to have an ideal audience member who has all the elements required to enjoy a piece, such as taste, education, etc. There are many accounts on what the aesthetic experience is, and some common threads are visible among them.
Kendal Walton believes that artistic creations are imitations that create a prop for a psychological state of fantasy. Those props exhibit some of the characteristics of the object or idea for which it serves as a prop. These simulations allow us to project ourselves into an imaginary situation creating a virtual world. By entering the fantasy, effects are generated in the audience. As an example, Walton takes a painting of a shipwreck and says one feels a simulated fear of the shipwreck and awe at the power of the sea, yet at the same time knows that they are not in danger and that the experience is a simulation. It's an imaginary fear and a respect for the power of nature. These effects are greater than real in the sense that the painting is two dimensional, and yet it evokes the feelings of a real event. The effects are less than real because one knows there is no real danger as there would be in the actual depicted event. .
Walton's "prop" theory makes a lot of sense to me and his example of the shipwreck is a valid one. Paintings and other artistic expressions are tools to spur the imagination into entering the piece and finding meaning there.