How Is Shell Structure Evidenced in Atomic Nuclei?

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Homework Statement



(a) What shows the existence of shell structure? What are the other numbers?

(b) Deduce the spin and parities.

shellstructure1.png


Homework Equations

The Attempt at a Solution



The shell model is given by:

shellmodel1.png


So for Li, 3 protons pair up with 3 neutrons, leaving an unpaired neutron in ##1p_{\frac{3}{2}}##. Thus S = 3/2. It's parity is odd.

For Oxygen, 8 protons pair up with 8 neutrons, leaving the unpaired neutron at ##1d_{\frac{5}{2}}##. Thus S = 5/2. Parity is odd.

For Neon, 10 protons pair up with 10 neutrons. it's even-even. Parity is even.

For Aluminium, 13 protons pair up with 13 neutrons, leaving the unpaired neutron is in ##1d_{\frac{5}{2}}##. Thus S = 5/2. Parity is odd.

For Nitrogen, 7 protons pair up with 7 neutrons. No unpaired?

For Potassium, 19 protons pair up with 19 neutrons, leaving unpaired neutron at ##1d_{\frac{3}{2}}##.

For Scandium, 20 protons pair up with 20 neutrons, leaving unpaired proton at ##1f_{\frac{7}{2}}##.
 
on Phys.org
Protons don't pair up with neutrons, they are different particles. Protons can pair up with protons, and neutrons with neutrons.
 
mfb said:
Protons don't pair up with neutrons, they are different particles. Protons can pair up with protons, and neutrons with neutrons.
OK, I got it. How do you determine the parity then? Say for Oxygen, there is 1 unpaired neutron in 1d(5/2). What is its parity?