Experimental observation of line hyperfine structure with a plane grating spectrograph

Abstract

For observing the hyperfine structure (HFS) of spectral lines it is required that the spectral bandwidth is smaller than or equal to both the physical widths of the HFS components and the wavelength distances between these components. The paper discusses how these conditions can be fulfilled for a 2.1-m plane grating spectrograph equipped with a 1200 grooves/mm grating. Using such a spectrograph observations were made of the HFS of lines emitted by hollow cathode lamps or an arc. Typical results for lines of Bi, Cu and In are reported. Wavelengths and relative intensities of HFS components are given.