Far-IR Excited OH Lines from Orion KL Outflows

摘要: As part of the first far-IR line survey towards Orion KL, we present detection seven new rotationally excited OH �–doublets (at ∼48, ∼65, ∼71, ∼79, ∼98 and ∼115 µm). Observations were performed with Long Wavelength Spectrometer (LWS) Fabry–Perots on board Infrared Space Observatory (ISO). In total, more than 20 resolved rotational lines, upper energy levels up to ∼620 K, have been detected at an angular velocity resolutions ∼80 ′′ ∼33 km s −1 respectively. profiles show a complex behavior evolving from pure absorption, P–Cygni type emission. We also large scale 6 ′ declination raster in 2 �3/2 J=5/2 + –3/2 − J=7/2 –5/2 lines 119.441 84.597 µm) revealing decrease excitation outside core cloud. From observed profiles, mean intrinsic widths offsets between emission absorption peaks conclude that most arises outflow(s), i.e. “plateau” spectral component. determine averaged abundance relative H2 �(OH)=(0.5–1.0)×10 −6 , kinetic temperature &100 K density n(H2)≃5×10 5 cm −3 . Even these conditions, is heavily coupled strong dust continuum inner ”hot core” regions expanding flow itself. Subject headings: infrared: ISM —ISM: individual (Orion KL)—ISM: jets outflows molecules — radiative transfer