FABRY-PEROT IMAGING OF MOLECULAR-HYDROGEN EMISSION IN ORION-KL REGION

A continuum-subtracted image of the H-2 v=1-0 S(1) line covering the c entral 4' square portion of the Orion-KL region, has been obtained usi ng a wide-field Fabry-Perot imager at the Communications Research Labo ratory 1.5 m telescope. Nine H-2 peaks (including four newly identifie d) are found in the core, as well as a curved, bridgelike structure th at encroaches on the inner edge of the disk structure observed in CS ( J = 1-0) emission. This existence of the bridge indicates that the out flow from IRc2 occurs not only toward the bipolar axis but also toward the disk, and suggests channeling by the disk of a more or less isotr opic flow from IRc2 into a bipolar flow. Outside the core, where finge r-like features of H-2 emission are seen, we identify 43 hot H-2 clump s. These are located along filamentary structures seen in CS (J = 1-0) maps and avoid peaks of CS intensity. The geometrical thickness of th e hot H-2 in these features is much smaller than their typical dimensi ons. We conclude that the H-2 emission from the clumps is radiated at the surfaces of the CS filaments, implying that outflow from IRc2 shoc ks the H-2 at the surfaces. From comparison of polarization measuremen ts of Burton et al. (1991) with the present measurements, as well as f rom discussion of the energetics, we rule out the possibility that the H-2 clumps are due to reflection.