It's been quite awhile since I thought about energy levels of nucleus.

My guess is that energy of the nucleus is unaffected.  Nuclear force is after all very short range and only involves interaction of protons and nucleons.

Of course, you have now created a positive ion and an electron which might be viewed as a higher-energy level system than the original atom.  Energy was required to do work against electrostatic force while pulling the electron out of the atom... that energy is converted to potential energy of the separated system... and that energy could be recovered if you allowed the electrostatic attraction to bring the particles back together and recombine.

Suggestion: The remaining group of particles will became positive since the electron charge (very small in comparison to neutrons) will be missing from that group. However, the group of particles may also be neutral (will not be positive) if the electron happened to be in excess there, i.e. the group of particles was negative. However, the nucleus is will have the same energy level. The subparticle approach is not addressed in this posting (no supercollisions).

bbaskii:

I have been reading a book titled QED ,the strange theory of light and matter, the book is written by an highly intelligent man Richard P. Feynman. The book is written in laymen terms. The book, 152 pages, can be read in about 8 hrs. The topics of the book deals with the question you have asked. I have not read the fourth lecture within the book and would sepculate that it would be fould there. Hope this is of help and you have 8 hrs. to read this enlighting material.

xray;