 -decay theory Effects of assumptions Non-spherical nucleus If the nucleus has a radius that is non- uniform what does this mean for  -decay? Will.

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Presentation transcript:

 -decay theory Effects of assumptions

Non-spherical nucleus If the nucleus has a radius that is non- uniform what does this mean for  -decay? Will the decay directions be isotropic? If not, in what direction will more alpha particles be emitted and why? How do you test this experimentally?

R’R’ B’B’

Non-zero angular momentum Transition I P  I D + j   -particle is even-even Angular momentum of  -particle is all orbital

Non-zero angular momentum Added term due to non-zero angular momentum If > 0, effective V(r) increases. Implications for t 1/2 ?

Non-zero angular momentum Parity of  -particle  Parity is conserved in  -particle decay Therefore, we must conserve angular momentum and parity This leads to some selection rules…

Excited states of daughter nucleus What are effects of transitions to excited states of daughter nucleus? 0 E1E1 E2E2 P D Q-value is less Lifetime is longer! What does this mean for an  -particle energy spectrum?