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Table A.1

Elemental composition. a(b) means a × 10b.

Element Number fraction

H 1
He 7.59(–2)
C 2.70(–4)δCa
N 2.14(–5)
O 2.88(–4)
Mg 4.17(–6)
Si 7.94(–6)
S 1.91(–6)
Fe 4.27(–6)



depending on the amount of volatile carbon, see main text.

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