I had a little chat with SASAMOTO San on her pervious research on carbon-12. In ground state, carbon-12 is a stable nucleus with 6 protons and 6 neutrons. In one of the excited state, it will use alpha decay to release energy. According to alpha decay theory, an alpha particle should be formed before the decay and oscillates or hit the column potential barrier million and million of time to get tunneling through. And theory calculation on the wavefunction show that the excited carbon-12 will form 3 alpha particles.

since the 6 protons has 15 way to combine in group of 2, thus, there are 225 ways to form 3 alpha particles. And only 1 of them will finally get out. Will these multiplicity increase the chance for tunneling and reduced the lifetime?

SASAMOTO San studied the excited state. And she knew somebody studied the alpha decay. Thus, by compare the decay rate with other nuclei, may be we can find out the role of multiplicity in decay.

The ground state of alpha particle is spin zero. And a spin 1 state of it is about 20MeV. However, adding one more proton will greatly reduced the energy. What is going on in alpha particle?