Vacuum ultraviolet Si i wavelengths have been recalculated using all available low-pressure-source data. One hundred calculated and forty-one measured wavelengths, all with uncertainties less than 0.002 Å, should be useful as wavelength standards in the region 1560 to 2000 Å. Seventy-seven of the proposed standards were originally calculated by Radziemski and Andrew [ J. Opt. Soc. Am. 55, 474 ( 1965)]; although the two sets of wavelength values agree to within their uncertainties, the new set has a greater internal consistency. Included also is a complete list of low-pressure-source levels for Si i, which contains new values for 30 odd levels previously determined exclusively from relatively high-pressure (450–740 torr) arc data.
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