Emission‐Line Properties ofz > 4 Quasars
نویسندگان
چکیده
منابع مشابه
THE X-RAY PROPERTIES OF z[ 4 QUASARS
We report on a search for X-ray emission from quasars with redshifts greater than 4 using the ROSAT public database. Our search has doubled the number of z[ 4 quasars detected in X-rays from six to 12. Most of those known prior to this work were radio-loud and X-rayÈselected sources ; our study increases the number of X-rayÈdetected, optically selected z[ 4 quasars from one to seven. We present...
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ژورنال
عنوان ژورنال: The Astrophysical Journal
سال: 2002
ISSN: 0004-637X,1538-4357
DOI: 10.1086/324395