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PS of a continuous spectrum

The same mathematical procedure as in Appendix A is followed here. Starting from the Parseval's theorem (10), and taking into account the expression for the perturbation (4) it yields two oscillatory functions where interference terms can be neglected. It is easy to see that these terms go to 0 as $m \gg m_{02}$. On the other hand these terms are unbounded at $m=m_{01},m_{02}$. So the expression yields


\begin{displaymath} \int PS  dm=\frac{2 u_a^2 \mu}{L \Delta m_0^2 (1/4+\mu^2)} \... ...}{z^2} dz + \int \frac{(1- m_{01} \mu^{-1} z)}{z^2} dz \right] \end{displaymath} (14)

Now a variable change from $z$ to $m=\left({1/m_{0i}- \mu^{-1} z} \right)^{-1}$ is performed. This mathematical transformation is only related to the oscillatory terms. So we find


\begin{displaymath} \int PS  dm = \frac{2 u_a^2 \mu}{L \Delta m_0^2 (1/4+\mu^2)}... ...m_{01}^3}{m^3} \left(1-\frac{m_{01}}{m}\right)^{-2}\right]  dm \end{displaymath} (15)

As the integral limits are free the integrands must be equal,

\begin{displaymath} PS=\frac{2 u_a^2 \mu}{L \Delta m_0^2 (1/4+\mu^2)} \left[\fra... ...rac{m_{01}^3}{m^3} \left(1-\frac{m_{01}}{m}\right)^{-2}\right] \end{displaymath} (16)

This expresion gives an approximation to the amplitudes in the high wavenumber part of the spectrum.


 


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