Synthetic spectrum around He iiλ 1640.42 Å compared with the STIS observation. He abundances are green, dashed: −10.0, red, thick: −4.7, blue, thin: −4.2, blue, dashed: −3.1. The insert shows the region Δλ = ± 0.4 Å around the He ii line. For comparison, the observation was smoothed with a low-pass filter (Savitzky & Golay 1964, n = 15, m = 4).
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