Wavelengths and Energy Levels of Singly Ionized Copper, Cu II

摘要

For the purpose of calculating wavelength standards in the vacuum ultra¬violet spectral region, the spectrum of singly ionized copper, Cu II, has been investigated photographically from 1979 to 11227 A using plane and concave grating spectrographs and Fabry-Perot interferometers. The light source employed was a water-cooled, hollow-cathode discharge tube operated with helium or neon. In the wavelength region studied, 1968 lines have been meas¬ured, 1011 of them interferometrically, and 1125 lines are newly observed. In the analysis, 102 new energy levels have been identified, bringing the total number of known even levels to 173, and the odd to 178. The wavelengths of 485 lines in the vacuum ultraviolet region were calculated using the Ritz com¬bination principle. Of these, 409 lines, with uncertainties of 0. 0001 to 0.0005 A, are recommended for use as wavelength standards.