MEAN AND EXTREME RADIO PROPERTIES OF QUASARS AND THE ORIGIN OF RADIO EMISSION
MEAN AND EXTREME RADIO PROPERTIES OF QUASARS AND THE ORIGIN OF RADIO EMISSION
复制标题
DOI：
10.1088/0004-6256/149/2/61
复制
发表时间：
2014-05
期刊：
影响因子：
--
通讯作者：
Rachael M. Kratzer;G. Richards
中科院分区：
文献类型：
--
作者：
Rachael M. Kratzer;G. Richards
我们研究了类星体的射电响度（RLF）和（使用叠加分析）平均射电响度的演变。我们考虑这些特性如何随着红移和光度、黑洞（BH）质量和吸积率以及与宽发射线区域中风的主导地位相关的参数而演变。我们将 FIRST 源目录与主要来自斯隆数字巡天的发光类星体样本（光谱和光度）进行匹配。在考虑了高红移下 BH 质量估计的灾难性误差后，我们发现 RLF 和平均射电光度都会随着 BH 质量的增加和吸积率的降低而增加。类似地，类星体的 RLF 和平均无线电响度都会增加，这些类星体被认为具有较弱的辐射线驱动的宽发射线区域的风分量。与过去的工作一致，我们发现 RLF 随着光学/紫外光度的增加和红移的减少而增加，而平均无线电响度以完全相反的方式演变。 L − z ?> 中平均无线电响度和 RLF 之间的行为差异可能表明选择效应会影响我们对 RLF 演变的理解；需要对光学和无线电进行更深入的调查来解决这种差异。最后，我们认为射电响（RL）和射电静（RQ）类星体可能是平行序列，但只有分布极端的 RQ 类星体才可能成为 RL，这可能是通过自旋和/或合并历史的微小差异。
We investigate the evolution of both the radio-loud fraction (RLF) and (using stacking analysis) the mean radio loudness of quasars. We consider how these properties evolve as a function of redshift and luminosity, black hole (BH) mass and accretion rate, and parameters related to the dominance of a wind in the broad emission-line region. We match the FIRST source catalog to samples of luminous quasars (both spectroscopic and photometric), primarily from the Sloan Digital Sky Survey. After accounting for catastrophic errors in BH mass estimates at high redshift, we find that both the RLF and the mean radio luminosity increase for increasing BH mass and decreasing accretion rate. Similarly, both the RLF and mean radio loudness increase for quasars that are argued to have weaker radiation line driven wind components of the broad emission-line region. In agreement with past work, we find that the RLF increases with increasing optical/UV luminosity and decreasing redshift, while the mean radio loudness evolves in the exact opposite manner. This difference in behavior between the mean radio loudness and the RLF in L − z ?> may indicate selection effects that bias our understanding of the evolution of the RLF; deeper surveys in the optical and radio are needed to resolve this discrepancy. Finally, we argue that radio-loud (RL) and radio-quiet (RQ) quasars may be parallel sequences, but where only RQ quasars at one extreme of the distribution are likely to become RL, possibly through slight differences in spin and/or merger history.