Spectroscopic survey of QSOs to B = 22.5 - The luminosity function
Spectroscopic survey of QSOs to B = 22.5 - The luminosity function
复制标题
DOI：
10.1086/165984
复制
发表时间：
1988-02
期刊：
影响因子：
--
通讯作者：
D. Koo;R. Kron
中科院分区：
文献类型：
--
作者：
D. Koo;R. Kron
类星体光度函数的暗端是根据一个光谱样本估计的，该样本完整到B = 21.1，无偏到B = 22.6，这是迄今为止最暗的调查。光度函数较暗的部分可以描述为不随红移而改变的幂律。转换到一个陡峭的斜率发生在高光度和高红移。在光度-表面密度图中，这一特征对红移的依赖是连续的;没有证据表明在任何光度下红移都是截止的。提出了一种新的模型的演变，充分描述了数据的z大于1。由于类星体的发射率被确定为红移的函数，它表明，在传统的假设下，观测到的类星体不能解释由冈恩-彼得森测试所暗示的星系际介质的电离水平。45篇参考文献。
The faint end of the luminosity function for QSOs is estimated from a spectroscopic sample complete to B = 21.1 and unbiased to B = 22.6, the faintest survey so far. The fainter part of the luminosity function can be described as a power law that does not change with redshift. The turnover to a steeper slope occurs at high luminosity at higher redshift. The dependence on redshift of this feature in the luminosity-surface density diagram is continuous; no evidence is seen for a cutoff in redshift at any luminosity. A new model for the evolution is proposed that adequately describes the data for z greater than one. The emissivity due to QSOs is determined as a function of redshift, and it is shown that, under conventional assumptions, the observed QSOs cannot explain the level of ionization of the intergalactic medium implied by the Gunn-Peterson test. 45 references.