what will happen TO THE ATOM if electron end up inside the nucleus ( as in quantum tunnelling) ?
See if you can find an OLD SciAm article titled, "Mesonic Atoms". I'll try to find the details and update.
The workers shot negatively charged mesons into lead atoms and the "Orbits" of the mesons were inside the nucleus.
The lowest energy electron state in any atom has L = 0, and its wavefunction therefore overlaps the nucleus. In most cases, nothing at all happens, because the electron and proton don't have any way of interacting (not enough energy available). In a few cases it's energetically possible for the electron to be captured and turn the proton into a neutron. This is called electron capture or K-capture - see the Wikipedia article.
Thank you very much every one :)
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