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Systematic frequency shifts of the 467 nm electric octupole transition in 171Yb+

The 2S 1/2 (F = 0) →2F 7/2 (F = 3, mF = 0) transition at 467 nm in a single trapped, laser-cooled ion of 171Yb+ has the potential to be an extremely accurate optical frequency reference. The systematic shifts of the transition frequency currently make a significant contribution to the uncertainty on absolute frequency measurements of the transition. Here the systematic shifts of a recent absolute frequency measurement using a femtosecond laser frequency comb generator are evaluated, and realistic limits for the ultimate performance of the standard are estimated.