\(\Delta\sigma_z = \frac{3}{2\pi} \left[ \frac{1}{1 + \left( \frac{r}{z} \right)^2} \right]^{\frac{5}{2}} \cdot \frac{Q}{z^2}\)

\(\Delta\sigma = q_{\omicron} I_c\)

\[ I = \frac{1}{4\pi} \left( \frac{2mn\sqrt{m^2 + n^2 + 1}}{m^2 + n^2 + m^2n^2 + 1} \cdot \frac{m^2 + n^2 + 2}{m^2 + n^2 + 1} + \tan^{-1} \left( \frac{2mn\sqrt{m^2 + n^2 + 1}}{m^2 + n^2 + 1 - m^2n^2} \right) \right) \]

WHERE

\( m = \frac{B}{z} \)

\( n = \frac{L}{7} \)