Deuterated Methanol in the Orion Compact Ridge

摘要

We show that, when these mantles are evaporated, the CH_2DOH/CH_3OD ratio can be altered by gas-phase reactions that preferentially form CH_3OD via reaction of H_2DO~+ with CH_3OH. We find that an unrea- listically high HDO/H_2O ratio of 0.1 is necessary to drive the CH_2DOH/CH_3OD ratio to within the observed range. Before concluding that the observed gas-phase CH_2DOH/CH_3OD ratio is inconsistent with these grain-surface reactions, we recommend that more accurate determinations of this ratio be made in the Compact Ridge and in other hot cores.