Warm Molecular Gas in the Outflow and Envelope of IRAS 12496-7650 (DK Cha)

dc.creatorvan Kempen, T. A.
dc.creatorHogerheijde, M. R.
dc.creatorvan Dishoeck, E. F.
dc.creatorGuesten, R.
dc.creatorSchilke, P.
dc.creatorNyman, L. -A.
dc.date2006-05-19
dc.date.accessioned2026-07-07T07:08:31Z
dc.date.available2026-07-07T07:08:31Z
dc.descriptionAims:To obtain insight into the physical structure of the warm gas in the inner envelope of protostars and the interaction with the outflow. Methods: Sub-millimeter observations of 12CO, 13CO and/or C18O in J=3-2, J=4-3 and J=7-6 were obtained with the APEX Telescope towards IRAS 12496-7650, an intermediate mass young stellar object. The data are compared to ISO-LWS observations of CO J=14-13 up to J=19-18 lines to test the different proposed origins of the CO lines. Results: The outflow is prominently detected in the 3-2 and 4-3 lines, but not seen at similar velocities in the 7-6 line, constraining the temperature in the high-velocity (> 5 km/s from line center) gas to less than 50 K, much lower than inferred from the analysis of the ISO-LWS data. In addition, no isothermal gas model can reproduce the emission in both the 7-6 and the higher-J ISO-LWS lines.The 7-6 line probably originates in the inner (<250 AU) region of the envelope at ~150 K. Detailed radiative transfer calculations suggest that the ISO-LWS lines are excited by a different mechanism, possibly related to the larger-scale outflow. All possible mechanisms on scales smaller than 8 " are excluded. High-resolution continuum as well as high-J 12CO and isotopic line mapping are needed to better constrain the structure of the warm gas in the inner envelope and the interaction with the outflow.
dc.descriptionAccepted for A&A special issue on APEX first results. 4 pages, 2 figures
dc.identifierhttps://arxiv.org/abs/astro-ph/0605509
dc.identifierhttp://arxiv.org/abs/astro-ph/0605509
dc.identifier.urihttp://salesiana.dossiersoluciones.com/handle/123456789/110733
dc.subjectAstrophysics
dc.titleWarm Molecular Gas in the Outflow and Envelope of IRAS 12496-7650 (DK Cha)
dc.typetext

Files

Collections