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Fig. 4


Comparison of the He II 1640 Å (top: STIS spectrum) and 4868 Å (bottom: NOT spectrum) line profiles from Nov. 20/21. Note that the two spectral intervals were nearly simultaneous, making this comparison possible. The He II 4686 Å is severely blended but the line accounts for the excess emission. In the bottom panel, the He II 1640 Å line is shown (dashed line) for comparison scaled by the continuum flux.

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