An analysis of ultraviolet spectra of Extreme Helium Stars and new clues to their origins
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چکیده
Abundances of about 18 elements including the heavy elements Y and Zr are determined fromHubble Space Telescope Space Telescope Imaging Spectrograph ultraviolet spectra of seven extreme helium stars (EHes): LSE78, BD+1
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تاریخ انتشار 2005