%info@http:://golem.fjfi.cvut.cz/wiki/root/GW4reports \def\GWslide{\slide{Electron density $n_e$ interferometer measurement introduction (extreme simplification $B=0$)}{ \bc Electromagnetic transverse wave:\\ $E_x(z,t)=E_0\cos(\omega t+kz)$ \twocolumns {0.5}{ \underline{Maxwell Equations@Vacuum:} $\begin{array}{ccc} \nabla \cdot \vec E & = & 0 \\ \nabla \cdot \vec B & = & 0 \\ \nabla \times \vec E & = & - \partial_t \vec B \\ \nabla \times \vec B & = & \mu_0 \epsilon_0 \partial_t \vec E \end{array}$\\ $\Longrightarrow$\\ %Dispersion relation: $\omega^2=k^2c^2$: The refractive index: $N=1$\\ } {0.5}{ \underline{Maxwell Equations@Plasma:} $\begin{array}{ccc} \nabla \cdot \vec E & = & \rho/\epsilon_0 \\ \nabla \cdot \vec B & = & 0 \\ \nabla \times \vec E & = & - \partial_t \vec B \\ \nabla \times \vec B & = & \mu_0 \vec J + \mu_0 \epsilon_0 \partial_t \vec E \end{array}$\\ $\Longrightarrow$ The refractive index: $N=\sqrt{1-\frac{{\omega _p}^2}{\omega ^2}}\approx 1-\frac{ne^2}{2\varepsilon_0m\omega^2}$ %Dispersion relation: $\omega^2=k^2c^2+w_{pe}^2$: } The phase shift:\\ $\Delta\varphi=-\frac{e^2}{2c\varepsilon_0 m\omega}\int_0^L n(l) \, dl$ \ec \credit{underthehood.blogwyrm:PlasmaWaves, Bartels:IPPlectures, MatenaMT}{} }}