A very large aperture spectrometer for low light optical emission spectroscopy

In low light experiments such as low temperature plasma or astronomical spectroscopy usual tools such as Czerny Turner based spectrometer (CTS) may have a limited efficiency due to the fact that a large entrance slit implies a large broadening of the instruments profile. To overcome the brightness issue of spectrometer, the so-called Bowen Chamber spectrometer (BCS) was designed to accept a large aperture slit, without significant deterioration of the spectrum. The BSC characteristics are presented and a close comparison with a CTS spectrometer is detailed. A simple geometrical model have been developed to still improve the BSC specifications.