Modern Wavelength Standards in the Ultraviolet and Vacuum Ultraviolet
Joseph Reader, Craig J. Sansonetti
In recent work at the National Institute of Standards and Technology the Atomic Spectroscopy Group has characterized several sources of wavelength standards useful for remote sensing applications. At low resolution, mercury pencil-type lamps are convenient for use either in the laboratory or the field. We recommend wavelengths for this lamp with an uncertainty of 0.001 in the region 2536 to 5790 . We also provide relative irradiances for the most prominent Hg lines, data that can be used to determine instrumental response. For high-resolution applications, we have measured wavelengths and relative intensities emitted by a commercial Pt/Ne hollow cathode lamp. Wavelengths for 5600 lines from 1130 } to 4330 , some with uncertainties as small as 0.0004 , are available in a comprehensive atlas of this lamp. Excellent calibration lines can also be obtained from demountable hollow cathode lamps. We review wavelength standards in Fe I and II, Th I and II, Ar II, and Cu II that can be excited in such lamps. Cu II provides wavelengths with uncertainties of less than 0.0004 from 670 through the entire ultraviolet region. For calibrations at shorter wavelengths, we have developed accurate standards that can be excited in a sliding-spark discharge with yttrium electrodes.
Proceedings of the 44th annual SPIE meeting and exhibition