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Rocket Observations of Far-Ultraviolet Dust Scattering in NGC 2023

Eric B. Burgh·Stephan R. McCandliss·Paul D. Feldman
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Abstract

The reflection nebula NGC 2023 was observed by a rocket-borne long-slit imaging spectrograph in the 900 -- 1400 Angstrom bandpass on 2000 February 11. A spectrum of the star, as well as that of the nebular scattered light, was recorded. Through the use of a Monte Carlo modeling process, the scattering properties of the dust were derived. The albedo is low, 0.2 -- 0.4, and decreasing toward shorter wavelengths, while the phase function asymmetry parameter is consistent with highly forward-scattering grains, g~0.85. The decrease in albedo, while the optical depth increases to shorter wavelengths, implies that the far-UV rise in the extinction curve is due to an increase in absorption efficiency.

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Eric B. Burgh, Stephan R. McCandliss, Paul D. Feldman. 2002-04-09. Rocket Observations of Far-Ultraviolet Dust Scattering in NGC 2023. https://doi.org/10.1086/341194

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