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Session 57 - Astrophysical Diagnostics from Polarimetry.
Display session, Wednesday, June 12
Tripp Commons,

[57.12] WUPPE Observations of the Reflection Nebula NGC 7023

A. D. Code, J. J. Johnson, C. M. Anderson, K. S. Bjorkman, B. Babler, G. K. Fox, M. R. Mead, W. Sanders, A. J. Weitenbecke (Univ. of Wisconsin), O. L. Lupie (STScI), R. J. Edgar (SAO)

During the March 1995 Astro-2 Mission the Wisconsin Ultraviolet Photopolarimeter Experiment (WUPPE) obtained spectropolarimetry of a region in the bright reflection nebula NGC 7023. The observations also included spectropolarimetry of the illuminating star HD 200775 and measurements of the instrumental scattered light contribution at the position of the nebular photometry. The observations provide a measurement of the ultraviolet polarization of the scattered light from the nebula and a measurement of the ultraviolet albedo. Of particular interest is the variations across the 2200 Angstrom extinction bump. The spectrum indicates an increase in albedo across the bump, contrary to the results that have been reported by other investigators (Witt,et al. 1992 ApJ 395 L5). The implications of these results are explored by comparison with possible models obtained by employing a Monte Carlo radiative transfer code.

Program listing for Wednesday