SIMBAD references

The HDO 1₀₁-0₀₀ ground-state line at 464GHz has been detected toward the high-mass star-forming clumps W3(OH) and W3(H₂O), together with the higher-lying 2₁₁-2₁₂ and 3₁₂-2₂₁ lines at 241 and 225GHz, respectively. A detailed analysis of the HDO excitation shows that the higher levels are most likely populated by intense far-infrared radiation due to warm dust. The data allow constraints on the dust temperature (T_dust>100K), total column of dust (E(B-V)>500mag) and HDO column density. Combined with H₂¹⁸O data recently obtained by Gensheimer et al., the deuteration of water is found to be lower than that of other species, [HDO]/[H₂O]=(2-6)x10^–4, but comparable to that found for other "hot cores".