具有最高红移（z~6）的类星体（QSO）是研究超大质量黑洞（BH）早期生长的独特探针。到目前为止，只有最明亮的类星体被研究过，通常一次只研究一个物体。在这里，我们提出了迄今为止最广泛的一致性分析z>4类星体与观测到的近红外光谱，结合我们正在进行的VLT-ISAAC计划的3个新的z~6对象与19个4<z<6.5来源的文献。新的光源将现有的SDSS样本扩展到类星体光度函数的暗端。使用极大似然拟合例程优化我们的光谱分解，我们估计的黑洞质量（MBH），爱丁顿比（定义为Lbol/LEdd）和Fe II/Mg II线比，一个代理的化学丰度，以表征中心对象和宽线区域气体。在我们的样本宿主黑洞中，质量约为10^9 M \odot的类星体正在接近爱丁顿光度的地方吸积，这与早期的结果一致。我们发现观测到的爱丁顿比的分布在较低的红移处与SDSS类星体的亮度匹配的比较样本的分布有显著的不同（0.35<z<2.25）：平均值<log（Lbol/LEdd）>=-0.37（Lbol/LEdd~0.43），对于z>4的样品具有0.20 dex的散射，并且对于<log（Lbol/LEdd）>=-0.80（Lbol/LEdd~0.16），对于0.35<z<2.25样品，分散度为0.24 dex。这意味着，在给定的光度下，高z的MBH通常低于低红移的平均MBH，即z>4的源比低红移的源吸积得更快。我们表明，派生的FeII/MgII的比例依赖于敏感的分析：我们的自洽，均匀的分析显着减少了FeII/MgII分散在以前的研究中发现。在红移范围4<z<6.5 [...]内，测量的Fe II/Mg II线比没有显示出随宇宙时间演化的迹象。
英文摘要：
[abridged] Quasars (QSOs) at the highest known redshift (z~6) are unique probes of the early growth of supermassive black holes (BHs). Until now, only the most luminous QSOs have been studied, often one object at a time. Here we present the most extensive consistent analysis to date of z>4 QSOs with observed NIR spectra, combining three new z~6 objects from our ongoing VLT-ISAAC program with nineteen 4<z<6.5 sources from the literature. The new sources extend the existing SDSS sample towards the faint end of the QSO luminosity function. Using a maximum likelihood fitting routine optimized for our spectral decomposition, we estimate the black hole mass (MBH), the Eddington ratio (defined as Lbol/LEdd) and the FeII/MgII line ratio, a proxy for the chemical abundance, to characterize both the central object and the broad line region gas. The QSOs in our sample host BHs with masses of ~10^9 M\odot that are accreting close to the Eddington luminosity, consistent with earlier results. We find that the distribution of observed Eddington ratios is significantly different than that of a luminosity-matched comparison sample of SDSS QSOs at lower redshift (0.35<z<2.25): the average <log(Lbol/LEdd)>=-0.37 (Lbol/LEdd~0.43) with a scatter of 0.20 dex for the z>4 sample and the <log(Lbol/LEdd)>=-0.80 (Lbol/LEdd~0.16) with a scatter of 0.24 dex for the 0.35<z<2.25 sample. This implies that, at a given luminosity, the MBH at high-z is typically lower than the average MBH of the lower-redshift population, i.e. the z>4 sources are accreting significantly faster than the lower-redshift ones. We show that the derived FeII/MgII ratios depend sensitively on the performed analysis: our self-consistent, homogeneous analysis significantly reduces the FeII/MgII scatter found in previous studies. The measured FeII/MgII line ratios show no sign of evolution with cosmic time in the redshift range 4<z<6.5 [...]
Wavelength-resolved reverberation mapping of intermediate redshift quasars HE 0413-4031 and HE 0435-4312: Dissecting Mg II, optical Fe II, and UV Fe II emission regions
Effects of heterogeneous data sets and time-lag measurement techniques on cosmological parameter constraints from MgII and CIV reverberation-mapped quasar data
Environment or Outflows? New insight into the origin of narrow associated QSO absorbers
最近对类星体光谱中窄吸收线系统的详细研究表明，至少有50%的类星体具有与中心引擎相关的窄吸收线，并且在大多数情况下，它们被发现是向外流出的。对NAL的研究是否会为无处不在的类星体反馈提供大量证据，从而阻止星系中恒星的形成？我提出了新的结果分布的视线之间的速度偏移的MgII吸收剂和他们的背景类星体，基于一个大的目录的吸收剂从SDSS DR 6和大大改善类星体红移的估计。我的分析揭示了一个高速人口的MgII NALS延伸到至少6000公里/秒的类星体，这不能归因于集群的本地星系，类似于最近观察到的CIV吸收器。在类星体的强电离场中存在这种低电离气体云表明，我们可能确实目睹了气体的机械排出，以及先前观察到的加热。我还表明，有一个显着过剩的低速MgII NALS在无线电响亮的类星体相比，无线电安静的类星体。在不久的将来，改进的类星体聚类结果将使我们能够判断这是由于环境还是反馈效应。
Consistency study of high- and low-accreting Mg ii quasars: No significant effect of the Fe ii to Mg ii flux ratio on the radius-luminosity relation dispersion
Assessing the dust selection bias in quasar absorbers at 0.7 < z< 1.6: Zn/Fe abundances in a radio-selected sample
完整的光学和无线电吸收线系统（CORALS）调查以前曾被用来证明z>1.6阻尼莱曼α系统的数密度，气体和金属含量在震级有限的调查中没有被显著低估。本文选取了在红移0.7 < z < 1.6范围内光学完全0.7 < z <0.5的Mg Ⅱ强吸收体样品< 1.6 CORALS sample of Ellison et al. is used to assess the potential of dust bias at intermediate redshifts. From echelle spectra of all CORALS absorbers with MgII lambda 2796 and FeII lambda 2600 rest equivalent widths >，测定了Zn、Cr、Fe、Mn和Si的柱密度。的范围内的灰尘，金属比和推断的数密度的DLAs从D-指数是一致的光学样品。我们还报道了在红移范围1.7 < z< 2.0的阶梯光栅数据中发现的4个新吸收体，其中两个是确认的DLA，一个是亚DLA，而第四个Lya线没有被覆盖。
