# Homework Help: Nuclear Physics: charmed baryons

1. Apr 17, 2012

### erogard

Hi,

So I have this problem about baryons:

The lightest charmed baryons have quark compositions cab with zero angular momentum (L_12 = L_3 = 0) where c is the charmed quark and a & b can be any of the light quarks (u, d, s).

Show that the resulting states can be classified into 3 families:

(1) 1/2+ baryons in which the light quark pair ab has spin = 0

(2) 1/2+ baryons in which the light quark pair ab has spin = 1

(3) 3/2+ baryons in which the light quark pair ab has spin = 1

I have no idea how to do this. I have what might be the worst professor on earth for my nuclear physics class, who literally rambles on for an hour and write random stuff on the board without explaining sh*t. It's extremely frustrating. I do have a basic knowledge of quarks however, and their different flavors and properties.

If someone could simply set me on the right track (for #1) so I could continue on my own, I would be infinitely grateful.

Last edited: Apr 17, 2012
2. Apr 27, 2012

### awantae

Hi, erogard. Each quarks (u,d,s,c) has spin 1/2 , so the first two light quarks can combine into 2 groups, that is spin 1 and 0. For group of spin 0, baryons with spin 1/2 can be formed by combining with c quark. For group of spin 1, we can form baryons spin 1-1/2=1/2 and 1+1/2=3/2.

3. Apr 27, 2012

### vela

Staff Emeritus
If awantae's response seems confusing, you want to review the addition of angular momenta in quantum mechanics. Your QM text probably explicitly works out the case for two spin-1/2 particles.