Broadening of Fast-Beam Spectral Lines Due to Diffraction at the Entrance Slit of a Spectrometer,

摘要

We show experimentally and theoretically that adjustment of a spectrometer for observation of fast-beam spectral lines under conditions of minimum linewidth requires consideration of the effects of diffraction at the spectrometer's entrance slit. We obtain an approximate expression for the optimum entrance slit width to be used in order to avoid the pronounced broadening of the spectral lines that occurs for very narrow entrance slits. (Author)