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Shell model determining spin and parity

  1. Nov 20, 2008 #1
    shell model determining spin and parity - urgent

    1. The problem statement, all variables and given/known data

    Find the spin and parity of [tex] _{20}^{41}Ca [/tex] and [tex]_{20}^{40}Ca [/tex]

    2. Relevant equations

    http://hyperphysics.phy-astr.gsu.edu/hbase/Nuclear/shell.html


    3. The attempt at a solution

    For [tex]_{20}^{41}Ca [/tex]we've an odd number of neutrons which will lie in 1f(7/2) level
    so we have spin 7/2 and parity -

    For [tex]_{20}^{40}Ca [/tex] both the unpaired neutron and proon will be in the 1d(3/2) level which has parity +, do I need to add together the two spins in this level. So I'd get spin 3 with parity +.
     
    Last edited: Nov 20, 2008
  2. jcsd
  3. Nov 20, 2008 #2
    Thinking about it since the shell is full it can't contribute to spin.
     
  4. Nov 20, 2008 #3

    malawi_glenn

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    Ca-40 has two closed shells, and since then it should have 0+ according to the shell model, right?
     
  5. Nov 20, 2008 #4
    Yes, I think.

    If we had something like [tex]_{21}^{42}X[/tex]. Then we'd have an odd neutron and odd proton in the [tex]1f_{7/2}[/tex], the spins would add and we'd have spin 7 and parity -1?
     
  6. Nov 20, 2008 #5

    malawi_glenn

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    why negative parity?
     
  7. Nov 20, 2008 #6
    Oh yeah. Should multiply the parities and thus get positive parity right? Basically the angular momentums are "parallel".
     
  8. Nov 21, 2008 #7

    malawi_glenn

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    You can also have J_tot = 6,5,4,3,2,1,0.

    Remember how to add two angular momenta.
     
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