The X-ray properties of z > 4 quasars

被引：42

作者：

Kaspi, S ^{[1
]}

Brandt, WN ^{[1
]}

Schneider, DP ^{[1
]}

机构：

[1] Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA

来源：

ASTRONOMICAL JOURNAL | 2000年 / 119卷 / 05期

关键词：

galaxies : active; galaxies : nuclei; quasars : general; X-rays;

D O I：

10.1086/301362

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

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-ray-selected sources; our study increases the number of X-ray-detected, optically selected z > 4 quasars from one to seven. We present their basic X-ray properties and compare these with those of lower redshift quasars. We do not find any evidence for strong broadband spectral differences between optically selected z > 4 quasars and those at lower redshifts.

引用

页码：2031 / 2037

页数：7

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The X-ray properties of z &gt; 4 quasars

The X-ray properties of z > 4 quasars