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 ${}^{13}\mathrm{C}$,${}^{16}\mathrm{O}$, and ${}^{18}\mathrm{O}$ from Penning-trap mass spectrometry, we determine the atomic mass of ${}^{17}\mathrm{O}$ to be $M$[${}^{17}\mathrm{O}$] $=16.999\hspace{0.5em}131\hspace{0.5em}644(30)$ u, where the uncertainty is purely statistical. Using Penning-trap mass spectrometry, we have also directly determined the atomic mass of ${}^{17}\mathrm{O}$ with the more precise result $M$[${}^{17}\mathrm{O}$] $=16.999\hspace{0.5em}131\hspace{0.5em}756\hspace{0.5em}6(9)$ u. The Dunham-Watson model applied to the molecular spectroscopic data hence predicts the mass of ${}^{17}\mathrm{O}$ to better than 1 part in ${10}^8$.

• Received 15 February 2010

DOI:https://doi.org/10.1103/PhysRevA.81.064501