THE EXCITATION AND ABUNDANCE OF HDO TOWARD W 3(OH) (H2O)/

The HDO 1(01) - O-00 ground-state line at 464 GHz has been detected to ward the high-mass star-forming clumps W 3(OH) and W 3(H2O), together with the higher-lying 2(11) - 2(12) and 3(12) - 2(21) lines at 241 and 225 GHz, respectively. A detailed analysis of the HDO excitation show s that the higher levels are most likely populated by intense far-infr ared radiation due to warm dust. The data allow constraints on the dus t temperature (T-dust > 100 K), total column of dust (E(B - V) > 500 m ag) and HDO column density. Combined with (H2O)-O-18 data recently obt ained by Gensheimer et al. (1996), the deuteration of water is found t o be lower than that of other species, [HDO]/[H2O]=(2-6) 10(-4), but c omparable to that found for other ''hot cores''.