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Laser Guide Star Adaptive Optics Imaging Polarimetry of Herbig Ae/Be Stars

Marshall D. Perrin·James R. Graham·Paul Kalas·James P. Lloyd·Claire E. Max·Donald T. Gavel·Deanna M. Pennington·Elinor L. Gates
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Abstract

We have used laser guide star adaptive optics and a near-infrared dual-channel imaging polarimeter to observe light scattered in the circumstellar environment of Herbig Ae/Be stars on scales of 100-300 AU. We discover a strongly polarized, biconical nebula 10 arcseconds in diameter (6000 AU) around the star LkHa 198, and also observe a polarized jet-like feature associated with the deeply embedded source LkHa 198-IR. The star LkHa 233 presents a narrow, unpolarized dark lane consistent with an optically thick circumstellar disk blocking our direct view of the star. These data show that the lower-mass T Tauri and intermediate mass Herbig Ae/Be stars share a common evolutionary sequence.

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Marshall D. Perrin, James R. Graham, Paul Kalas, James P. Lloyd, Claire E. Max, Donald T. Gavel, Deanna M. Pennington, Elinor L. Gates. 2004-02-25. Laser Guide Star Adaptive Optics Imaging Polarimetry of Herbig Ae/Be Stars. https://doi.org/10.1126/science.1094602

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