The submillimeter wave spectrum of the protonated and deuterated carbon dioxide

The submillimeter wave spectrum of the protonated carbon dioxide has been investigated in the 340-406 GHz frequency range by using a phase locked submillimeter carcinotron. A magnetically confined glow discharge in a mixture of CO2, H2/D2, and Ar has been used to produce the molecular ions. The rotational lines investigated are characterized by J = 15-18, K-alpha not greater than 5 for HCO2(+) and J = 16-19, K-alpha not greater than 6 for DCO2(+). From the analysis of the spectra, accurate molecular constants have been derived, leading to the prediction of transitions of astrophysical interest.