I was making an exercise where I had to check if a decay is possible, so I checked if the baryon number, charge, energy, Lepton numbers, and spin are conserved. One of the decays is this one:
$\Sigma^0 \rightarrow \Lambda^0 + \gamma + \gamma$
All of the numbers were conserved except for the spin, so I thought that this meant that the decay was not possible. However, when I checked the solution, it didn't consider the spin. So my question is, should spin be conserved in a decay of elementary particles?