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Table 1

Helium line enhancement factors from different studies.

Study He i λ584 He ii λ304 He iiλ256

Jordan (1975) 15 5.5
MacPherson & Jordan (1999) 10–14 13–25
Pietarila & Judge (2004) 2–10 27
Giunta et al. (2015) 0.5–2 13 5
This work 7 10 7

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