\frac{\sigma(p+d\rightarrow {^3He}+\pi^0)}{\sigma(p+d\rightarrow {^3H}+\pi^+)}=\frac{|<\frac{1}{2}1 \frac{1}{2} 0|\frac{1}{2} \frac{1}{2}>|^2}{|<\frac{1}{2} 1 -\frac{1}{2} 1|\frac{1}{2} \frac{1}{2}>|^2}=2