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arXiv · 1011.4475

PACS spectroscopy of OH/IR stars

R. Lombaert·B. L. de Vries·L. Decin·J. A. D. L. Blommaert·P. Royer·E. De Beck·A. de Koter·L. B. F. M. Waters
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Abstract

Observations of high-excitation molecular emission lines can greatly increase our understanding of AGB winds, as they trace the innermost regions of the circumstellar envelope. The PACS spectrometer on-board the Herschel Space Telescope, provides for the first time the spectral resolution and sensitivity necessary to trace these lines. We report on the first modelling efforts of a PACS spectral scan for the OH/IR star V669 Cas. Central to our methodology is the consistent treatment of both dust and gas by using a line radiative transfer and a continuum radiative transfer code conjointly. Water emission lines are found to be extremely sensitive to the dust-to-gas ratio, emphasizing the need of consistent modelling for dust and gas.

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R. Lombaert, B. L. de Vries, L. Decin, J. A. D. L. Blommaert, P. Royer, E. De Beck, A. de Koter, L. B. F. M. Waters. 2010-11-19. PACS spectroscopy of OH/IR stars. https://arxiv.org/abs/1011.4475

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