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ORFEUS-SPAS II EUV Spectroscopy of epsilon Canis Majoris (B2 II)

David H. Cohen·Mark Hurwitz·Joseph P. Cassinelli·Stuart Bowyer
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Abstract

We report on extreme-ultraviolet (EUV) spectroscopic observations of the B bright giant epsilon Canis Majoris made during the ORFEUS-SPAS II mission. We assess the performance of the instrument in the EUV and find that the effective area is roughly 3 times that of the Extreme-Ultraviolet Explorer (EUVE) long-wavelength spectrometer and that the spectral resolution is lambda/Delta(lambda) = 1250. We identify most of the features, qualitatively compare different models, and examine the wind-broadened O V and Si IV lines, which display blue edge velocities up to 800 km/s.

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David H. Cohen, Mark Hurwitz, Joseph P. Cassinelli, Stuart Bowyer. 1998-05-20. ORFEUS-SPAS II EUV Spectroscopy of epsilon Canis Majoris (B2 II). https://arxiv.org/abs/astro-ph/9712093

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