Measurement of number density of lead and thallium see-through hollow cathode discharges with a high resolution Fabry–Pérot spectrometer and by conventional atomic absorption

Abstract

A see-through hollow cathode lamp, or galvatron, is investigated. A novel method is presented for the measurement of an atomic absorption profile using a quasi-continuum source created by the combination of two line sources and a high-resolution Fabry–Perot interferometer coupled to a spectrometer. Number densities are calculated from the resulting absorption profiles by the peak absorption coefficient relationship and compare well with results obtained from high-resolution emission measurements. Number densities are also determined for the lead 3 P 1 metastable state and thallium 2 P 1/2 o ground state by conventional atomic absorption. A hollow cathode lamp is used as an emission source and is set at a relatively low current to approximate as a line source relative to the galvatron. Due to the relative line widths of the source and absorber, only the lead metastable state results compare to results obtained by saturated fluorescence.