Soft X-Ray Absorption by High-Redshift Intergalactic Helium
نویسندگان
چکیده
منابع مشابه
Soft X-Ray Absorption by High-Redshift Intergalactic Helium.
The Lyalpha absorption from intergalactic, once-ionized helium (He ii) has been measured with the Hubble Space Telescope in four quasars over the last few years in the redshift range 2.4<z<3.2. These observations have indicated that the He ii reionization may not have been completed until z approximately 2.8 and that large fluctuations in the intensity of the He ii-ionizing background were pres...
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ژورنال
عنوان ژورنال: The Astrophysical Journal
سال: 2000
ISSN: 0004-637X
DOI: 10.1086/312418