Corrections to the nuclear Goldberger-Treiman relation and the pionic nuclear form factor are investigated using the $\Delta J=0\mathrm{}$ transition with parity change as an example of forbidden transitions. It is shown that (1) the corrections are as large as the main term, implying that the original Goldberger-Treiman relation with pion-pole dominance is no longer valid, (2) the pionic form factor $f_{\pi \mathrm{if}}\left(q^2\right)$ is a very rapidly varying function of $q^2$ for $\left|q^2\right|<\mathrm{}m_{\pi }^{}{}_{}{}^2$, and (3) the ratio [$\frac{f_{\pi \mathrm{if}}\mathrm{}\left(0\right)\mathrm{}}{f_{\pi \mathrm{if}}(-m_{\pi }^{}{}_{}{}^2)}$] is essentially zero.

• Received 20 February 1975

DOI:https://doi.org/10.1103/PhysRevD.11.3347