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Session 50 - Molecular Outflows, Stellar Jets, and Herbig-Haro Objects.
Display session, Tuesday, January 14
We present near-infrared images of Cep A East exhibiting two diffuse emission features: a reflection nebula and (presumably shock excited) line emission. We have generated color maps of Cep A East using broadband images taken at 4.67 \mum, 3.81 \mum, and 2.158 \mum showing the gradient of extinction across the reflection nebula. High degrees of polarization observed at 2.2 \mum (Casement amp; McLean, ApJ, 462 , 797, 1996) and 3.6 \mum (Lenzen et al, A amp; A, 137 , 202, 1984) imply scattered starlight; at longer wavelengths, the emission could possibly have a thermal component. Investigation of various point sources which become more apparent at longer wavelengths prompts us to consider whether they and/or the compact sources in HW2 and HW3 are the exciting sources.
We also present our current interpretations of near-infrared spectroscopic imaging (R = 800) of Cep A East in the molecular hydrogen, v: 1--0 S, 2.122 \mum line and the forbidden ionized iron 1.644 \mum line. Two distinct regions of presumably shocked excited line emission are observed in both lines: a southern `interstellar bullet' (Burton amp; Allen, Nature, 363, 54) consisting of an iron knot followed by a molecular hydrogen tail, and a northern region of more diffuse emission.
All observations were carried out at the Wyoming Infrared Observatory 2.3 m telescope with the University of Rochester 3rd Generation Infrared Camera. The spectroscopic imaging was accomplished in conjunction with the Naval Research Laboratory and National Air and Space Museum Fabry-Perot Interferometer.
Program listing for Tuesday