Mass of 17O from Penning-trap mass spectrometry and molecular spectroscopy: A precision test of the Dunham-Watson model in carbon monoxide

By fitting the Dunham-Watson model to extensive rotational and vibrational spectroscopic data of isotopic variants of CO, and by using existing precise masses of C-13, O-16, and O-18 from Penning-trap mass spectrometry, we determine the atomic mass of O-17 to be M[O-17] = 16.999 131 644(30) u, where the uncertainty is purely statistical. Using Penning-trap mass spectrometry, we have also directly determined the atomic mass of O-17 with the more precise result M[O-17] = 16.999 131 756 6(9) u. The Dunham-Watson model applied to the molecular spectroscopic data hence predicts the mass of O-17 to better than 1 part in 10(8).