The thick-target yield of gamma rays from the ($p, p^{\prime }\gamma$) reaction has been used to calculate values of the strength function $\frac{{〈{\gamma }^2〉}_{\mathrm{Av}}}{\overline{D}}$, of states in the compound nucleus for the channel of $s$-wave inelastic protons. Measurements of inelastic scattering to the 2+ first excited states of nine even-even nuclides, ranging from ${\mathrm{Ca}}^{44}$ to ${\mathrm{Zn}}^{64}$, indicate a constant value for $\frac{{〈{\gamma }^2〉}_{\mathrm{Av}}}{\overline{D}}$ of 2.7×${10}^{-14\mathrm{}}$ cm, within experimental error. This may be compared with the resonance in neutron strength function near atomic weight 55 as found in neutron elastic scattering.

• Received 8 April 1957

DOI:https://doi.org/10.1103/PhysRev.107.547