2013A&A...549A..96H

Glycolaldehyde (CH₂OHCHO) is the simplest sugar and an important intermediate in the path toward forming more complex biologically relevant molecules. Astronomical surveys of interstellar molecules, such as those available with the very sensitive ALMA telescope, require preliminary laboratory investigations of the microwave and submillimeter-wave spectra of molecular species including new isotopologs - to identify these in the interstellar media. To achieve the detection of the ¹³C isotopologs of glycolaldehyde in the interstellar medium, their rotational spectra in the millimeter and submillimeter-wave regions were studied. The spectra of ¹³CH₂OHCHO and CH₂OH¹³CHO were recorded in the 150-945GHz spectral range in the laboratory using a solid-state submillimeter-wave spectrometer in Lille. The observed line frequencies were measured with an accuracy of 30kHz up to 700GHz and of 50kHz above 700GHz. We analyzed the spectra with a standard Watson Hamiltonian. About 10000 new lines were identified for each isotopolog. The spectroscopic parameters were determined for the ground- and the three lowest vibrational states up to 945 and 630GHz. Previous microwave assignments of ¹³CH₂OHCHO were not confirmed. The provided line-lists and sets of molecular parameters meet the needs for a first astrophysical search of ¹³C-glycolaldehydes.