2011ApJ...737L..25M

For the first time, using the Submillimeter Array, H₂ CS emission was observed to show a typical bipolar outflow morphology toward DR21(OH). The emission consisted of a strong concentration toward a hot molecular core (MM1a) and a symmetrically extended feature aligned roughly in the north-south direction. H₂ CS is one of the hot core species, and its extended emission is expected to result from the interaction between the outflow of MM1a and the dense ambient gas. We derive H₂ CS column densities of ∼3x10¹⁵/cm2 and ∼1x10¹⁵/cm2 toward MM1a and the centers of the extended emission, respectively. Its fractional abundance, f (H₂CS) ∼ 10^–9 relative to the total H₂abundance, is comparable to those in other star-forming regions, suggesting that H₂ CS may be present in a region closer to the center than previously thought. Our results suggest that the observed H₂ CS emission arises via direct evaporation or sputtering of the solid H₂ CS on the grain surface, and H₂ CS may be one of the major sulfur-bearing species residing in the ice grain mantles in a solid form, at least in the case of DR21(OH).