VizieR Online Data Catalog: Line lists of transitions for interstellar urea (Remijan+, 2014)

The first measurements of the microwave spectra of urea were made from 5GHz to 50GHz using a heated waveguide cell (Brown et al., 1975JMoSp..58..445B). Further measurements were reported by Kasten & Dreizler (1986ZNatA..41.1173K) and Kretschmer et al. (1996MolPh..87.1159K). New spectroscopic measurements were made at NIST over the frequency range from 59GHz to 114GHz. A total of 38 rotational transitions was measured. Later, the Kharkov group carried out higher frequency measurements. Using a heated quartz absorption cell utilizing an automated synthesizer-based spectrometer (Ilyushin et al., 2005JMoSp.231...15I), the Kharkov group provided 75 new measurements between 78GHz and 240GHz. The urea lines for which we searched were calculated using the millimeter-wave data discussed above, as well as the hyperfine-free data from the existing literature cited earlier.

As an aid to further interstellar searches for urea transitions, we provide a complete list of predicted rotational lines of urea available in Table6 covering the frequency range of 1GHz to 600GHz.

(1 data file).