First, I will admit I am not well read on the subject but I do have a few good books (and a lot of documentaries) under my belt. As far as I understand it most of the household names we know concerning the atomic golden age are not the theorists that led to the prospect of unlocking nuclear energy itself but instead were more like the generation of minds that finally had the tools and the opportunity to pull it all together into reality.
You should read the first half or so of Richard Rhodes' The Making of the Atomic Bomb. It goes into very vivid detail about the scientific discoveries and people who set the stage for the work. There is no clean line to draw between theorists and experimentalists in terms of who made contributions — both did, in tandem. The work could not be done without both. Rutherford, Soddy, Bohr, the Curies, Szilard, Fermi, Lawrence, Compton, Oppenheimer... there are a lot of them.