Question #43792

Two coherent point sources, $S_1$ and $S_2$, are created using specialized stimulated emission setups. Source $S_1$ emits photons exclusively from the $n=4 \to n=2$ transition of $He^+$ ions, while source $S_2$ emits photons exclusively from the $n=8 \to n=4$ transition of $Be^{3+}$ ions. At a point $P$ on a detector, the independent photon flux (number of photons crossing per unit area per unit time) received from $S_1$ is $N_0 \text{ m}^{-2}\text{s}^{-1}$, and from $S_2$ is $4N_0 \text{ m}^{-2}\text{s}^{-1}$. The electromagnetic waves from both sources are polarized in the same plane and arrive at $P$ with a path difference of $\Delta x = \frac{\lambda}{3}$, where $\lambda$ is the wavelength of the $He^+$ emission. Given that the ground state energy of a hydrogen atom is $E_H = 13.6 \text{ eV}$, what is the net time-averaged electromagnetic wave intensity detected at point $P$?