First row is real. Second row, not so much.

That said, the "one big nucleon" is pretty close in concept to a neutron star. It needs a few more nucleons than there are in a single atom though. Just a few. And it's not really a decay mode as it is a gravitational effect.

It's also kind of reminiscent of superatoms - clusters of atoms that act like one single atom - but that is very much not the same. (The nuclei aren't fused. They maintain regular, sensible, atomic distances. Electrons are free to pass between. etc.)