<math> \zeta^\alpha(\omega)=\{{\rm det}(\Sigma)^{\frac{1}{2}}{\rm pdet}(A^T\Sigma^{-1} A)^{\frac{1}{2}}\}^{-\frac{\alpha}{2}}\exp\left\{-\frac{\alpha}{2}\left(\omega^T(A^T\Sigma^{-1}A)^{\dagger}\omega\right)\right\} | <math> \zeta^\alpha(\omega)=\{{\rm det}(\Sigma)^{\frac{1}{2}}{\rm pdet}(A^T\Sigma^{-1} A)^{\frac{1}{2}}\}^{-\frac{\alpha}{2}}\exp\left\{-\frac{\alpha}{2}\left(\omega^T(A^T\Sigma^{-1}A)^{\dagger}\omega\right)\right\} |