Influence of the width of the exciting line on the coherent emission due to stimulated Raman scattering

An investigation was made of the dependence of the coherent emission efficiency of a Raman laser on the width of the exciting line $\Delta\nu_{\text{e}}$. It was found that the emission efficiency remained constant up to $\Delta\nu_{\text{e}}\lesssim 2\Delta\nu_{\text{sp}}$, where $2\Delta\nu_{\text{sp}}$ is the width of the spontaneous scattering line. The efficiency fell by an order of magnitude in the range $\Delta\nu_{\text{e}}\gtrsim10\Delta\nu_{\text{sp}}$.