We report the observation of the hitherto undetected v′=8←v=0 vibrational overtone in trapped HD+molecular ions, sympathetically cooled by laser-cooled Be+ions. The overtone is excited using 782 nm laser radiation, after which HD+ions in v=8 are photodissociated by the 313 nm laser used for Be+cooling. The concomitant loss of HD+is detected by the method of secular excitation (Roth et al. in Phys. Rev. A. 74:040501(R), 2006). We furthermore present details of the experimental setup, and we show that results from spectroscopy of v′=8←v=0 overtones in combination with accurate ab initio calculations may yield a new value for the proton-electron mass ratio with an accuracy of order 1 ppb.

doi.org/10.1007/s00340-011-4802-y, hdl.handle.net/1765/33987
Applied Physics B
Erasmus MC: University Medical Center Rotterdam

Koelemeij, J. C. J., Noom, D. W. E., de Jong, D., Haddad, M. A., & Ubachs, W. (2011). Observation of the v′=8←v=0 vibrational overtone in cold trapped HD
+. Applied Physics B, 1–11. doi:10.1007/s00340-011-4802-y