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Fig. 2
Comparison of He II 1640 Å (solid) with He II 4686 Å (dot-dash) from epoch 1 (top) and epoch 2 (bottom). All spectra were dereddened with E(B − V) = 0.5. For display purposes, the optical NOT spectrum is multiplied by a factor of 40 with a boxcar smoothing to 11 points.
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