Sum Rules for Photodisintegration ofH3andHe3

We apply the sum rules of Levinger and Bethe to calculate the dipole bremsstrahlung weighted cross section (${\sigma }_b=\int 0^{\infty }\left(\frac{\sigma }{W}\right)dW$) and the integrated cross section (${\sigma }_{\mathrm{int}}=\int 0^{\infty }\sigma \mathrm{dW}$) for ${\mathrm{H}}^3$ and ${\mathrm{He}}^3$ using Irving's wave function. On assuming charge symmetry and neglecting Coulomb repulsion, we find that ${\sigma }_b\left({\mathrm{H}}^3\right)={\sigma }_b\left({\mathrm{He}}^3\right)$ and ${\sigma }_{\mathrm{int}}\left({\mathrm{H}}^3\right)={\sigma }_{\mathrm{int}}\left({\mathrm{He}}^3\right)$.