High resolution millimeter-wave to infrared spectroscopy of circumstellar disks
- Creators
-
Blake, Geoffrey A.
- Others:
- Caroff, L.
- Moon, L. J.
- Backman, D.
- Praton, E.
Abstract
The role of high spectral and spatial resolution spectroscopy in understanding the evolution of the gaseous component of circumstellar accretion disks is described. Millimeter-wave emission lines from trace constituents such as CO, CN, HCO+, and HCN can be used to probe the kinematic and physicochemical properties in the near-surface regions of disks beyond 100 AU, but, thanks to extensive molecular depletion in the midplane, they are not a reliable proxy for the disk mass. Mid-infrared observations of the pure rotational transitions of molecular hydrogen would alleviate many of these concerns, and results from the ISO SWS instrument on several \transitional" disks are presented. The measurements of these weak lines used beams substantially larger than the disk angular diameter, and so must be verified or refuted by high angular resolution spectroscopy from the ground. Finally, the high resolution M-band (5 µm) spectroscopy of CO in disks is outlined. Emission lines that are likely optically pumped by hot dust in the inner disk (R ≾ 1 AU) are seen toward inclined systems, while the absorption spectra of edge-on disks clearly reveal the molecular depletion inferred at millimeter-wavelengths.
Additional Information
© 2004 Astronomical Society of the Pacific. The results outlined here form the thesis and postdoctoral research of several young scientists at Caltech and in Prof. Ewine van Dishoeck's astrochemistry group at Leiden University with whom it has been my great privilege to learn these past several years. Their dedication and camaraderie are gratefully acknowledged. The OVRO Millimeter Array and Caltech Submillimeter Observatory are operated with support from the National Science Foundation, grants AST 99-81546 and AST 99-80846. The NIRSPEC data were obtained at the Keck II telescope of the W.M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W.M. Keck Foundation.Attached Files
Published - Blake_2004p79.pdf
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Additional details
- Eprint ID
- 34826
- Resolver ID
- CaltechAUTHORS:20121010-130405299
- NSF
- AST 99-81546
- NSF
- AST 99-80846
- W. M. Keck Foundation
- Created
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2012-10-12Created from EPrint's datestamp field
- Updated
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2019-10-03Created from EPrint's last_modified field
- Caltech groups
- Division of Geological and Planetary Sciences (GPS)
- Series Name
- Astronomical Society of the Pacific Conference Series
- Series Volume or Issue Number
- 324