منابع مشابه
Helium Absorption by Protogalactic Gas
We present a new, high resolution HST/GHRS spectrum of quasar Q0302003, and use the He Lyman-α absorption, together with a high resolution Keck spectrum of the HI Lyman-α forest, to probe the distribution and ionization state of the protogalactic foreground gas at z ≈ 3.3. Within ≈ 4000 km/sec of the quasar redshift the spectrum shows a substantial flux (τ ≈ 1) with “He Lyman-α forest” absorpti...
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ژورنال
عنوان ژورنال: Nature
سال: 1922
ISSN: 0028-0836,1476-4687
DOI: 10.1038/109112a0