What Determines the Spin and Parity of a Nucleus with Multiple Excited Nucleons?

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SUMMARY

The spin and parity of a nucleus with multiple excited nucleons is determined by considering all unpaired nucleons, not just the outermost one. In the case of a lithium-7 nucleus (Z=3) with a proton excited from the 1s1/2 state to the 2s1/2 state, the spin is calculated as (1/2)+, with the parity being negative due to contributions from the 1s and 2s protons being neutral and the unpaired proton in the 1p3/2 state contributing negatively. The smallest possible spin is 1/2 and the highest is 5/2, confirming that all unpaired nucleons contribute to the overall spin and parity of the nucleus.

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  • Understanding of nuclear structure and nucleon states
  • Familiarity with quantum numbers and their significance in nuclear physics
  • Knowledge of spin and parity calculations in quantum mechanics
  • Basic concepts of excited states in atomic nuclei
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stunner5000pt
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I understand that the spin and parity of the nucleus is determined by looking at hte unpaired nucleon (is that the correct way of saying it?). But what if we were looking at nulceus where 2 or more nucleons were excited from the ground state?? What would the spin and parity of the nucleus be, then??

What if we had a lithium-7 (Z=3) nucleus, say where the a proton from [itex]1s_{1/2}[/itex]was excited (by some means) to the [itex]2s_{1/2}[/itex] state. Now we have 2 unpaired protons, one in the [itex]1p_{3/2}[/itex] state and the [itex]2s_{1/2}[/itex]

what would the spin and the parity of this nucleus be??

Do we still look at the unpaired nucleon in the outermost shell only??
In this case, then the spin would be [itex](1/2)^+[/itex], since the j value of the outermost nucleon in 1/2 and l=0.

(Spin and parity is given by [itex]i^{\pi}[/itex]
where i=j
and [itex]\pi = (-1)^l[/itex])
 
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Old stuff, but let's give an answer: All unpaired nucleons contribute to spin and parity, that is ALL three protons. Smallest possible spin is 1/2 and highest 5/2. Parity is evidently negative (1s and 2s protons contribute nothing, the p proton contributes negative).
 

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