Should i contact my half brother?

Why not take it slow? Maybe contact him and just ask if he'd be willing to mail or email back and forth to get to know each other. You could even say, that in the future if you both think it is right you could even meet but you could take it slowly in the beginning. Before you contact him, make sure you know there is a chance he will not reply. Personally, I'd want to be 100% sure of the fact that I'd be okay with what ever choice he decided.