类星体光谱中的宽吸收线（BALs）确定了可能存在于所有类星体中的高速外流，并可能在星系演化的反馈中发挥重要作用。BALs的变化可以帮助我们了解流出的结构，演化和基本物理性质。在这里，我们报告了我们对24个红移为1.2<z<2.9的发光类星体样本进行的BAL监测活动的第一个结果，重点关注两个不同时间间隔的C IV 1549 BAL变化：类星体静止框架中的4至9个月（短期）和3.8至7.7年（长期）。我们发现39%（7/18）的类星体在短期内发生变化，而65%（15/23）的类星体在长期内发生变化，在长期数据中强度的典型变化更大。变异性通常仅发生在部分BAL谷中。在较高的出流速度的组件更容易变化比那些在较低的速度，和较弱的BALs更容易变化比强BALs。BAL强度的分数变化与BAL特征的强度呈负相关，但与流出速度无关。短期和长期数据都显示出相同的趋势。观察到的行为是最容易理解的结果，云的运动在连续源。如果交叉速度不超过局部开普勒速度，那么观测到的短期变化意味着吸收体距离中央类星体<6 pc。
英文摘要：
Broad absorption lines (BALs) in quasar spectra identify high velocity outflows that likely exist in all quasars and could play a major role in feedback to galaxy evolution. The variability of BALs can help us understand the structure, evolution, and basic physical properties of the outflows. Here we report on our first results from an ongoing BAL monitoring campaign of a sample of 24 luminous quasars at redshifts 1.2<z<2.9, focusing on C IV 1549 BAL variability in two different time intervals: 4 to 9 months (short-term) and 3.8 to 7.7 years (long-term) in the quasar rest-frame. We find that 39% (7/18) of the quasars varied in the short-term, whereas 65% (15/23) varied in the long-term, with a larger typical change in strength in the long-term data. The variability occurs typically in only portions of the BAL troughs. The components at higher outflow velocities are more likely to vary than those at lower velocities, and weaker BALs are more likely to vary than stronger BALs. The fractional change in BAL strength correlates inversely with the strength of the BAL feature, but does not correlate with the outflow velocity. Both the short-term and long-term data indicate the same trends. The observed behavior is most readily understood as a result of the movement of clouds across the continuum source. If the crossing speeds do not exceed the local Keplerian velocity, then the observed short-term variations imply that the absorbers are <6 pc from the central quasar.
窄吸收线流出是类星体流出现象中一个重要但知之甚少的部分。我们讨论了一个特定的NAL流出，具有高速度，时间变化性，和温和的电离，像典型的BAL流，在一个估计的位置只有约5个pc的类星体。它的总柱密度和线宽（内部速度分散）比BAL小~100倍，没有实质性的X射线吸收。我们认为，辐射屏蔽（在一个X-射线/温暖的吸收剂的形式）是不重要的外流加速和中度电离发生在密集的子结构，有一个整体的小体积填充因子的流量。我们还提出了类星体流出线的总体发生率的新估计;例如，大约43%的明亮类星体有C IV NAL流出，而大约68%的类星体有任何种类的C IV流出线（NAL，BAL或mini-BAL）。
It has been suggested that non-relativistic outflows from quasars can naturally account for the missing component of the extragalactic $γ$-ray background and explain the cumulative neutrino background through pion decay in collisions between protons accelerated by the outflow shock and interstellar protons. Here we show that the same quasar outflows are capable of accelerating protons to energies of $\sim 10^{20}$ eV during the early phase of their propagation. The overall quasar population is expected to produce a cumulative ultra high energy cosmic ray flux of $\sim10^{-7}\,\rm GeV\,cm^{-2}s…
Quasar-driven outflows naturally account for the missing component of the extragalactic $γ$-ray background through neutral pion production in interactions between protons accelerated by the forward outflow shock and interstellar protons. We study the simultaneous neutrino emission by the same protons. We adopt outflow parameters that best fit the extragalactic $γ$-ray background data and derive a cumulative neutrino background of $\sim10^{-7}\,\rm GeV\,cm^{-2}\,s^{-1}\,sr^{-1}$ at neutrino energies $E_ν\gtrsim 10$ TeV, which naturally explains the most recent IceCube data without tuning any fr…
Many theoretical models predict that quasar driven outflows account for the observed quenching of star formation in massive galaxies. There is growing observational evidence for quasar-launched massive outflows at z>6, while the details of outflow-host galaxy interaction remain obscure. In this paper, we study the feedback around the highest redshift quasar in the BlueTides simulation, the largest volume cosmological hydrodynamic simulation so far carried out. We present predictions for gas outflows around the brightest $z = 7.54$ quasar which hosts the most massive black hole in the simulatio…
The origin of the extragalactic $γ$-ray background permeating throughout the Universe remains a mystery forty years after its discovery. The extrapolated population of blazars can account for only half of the background radiation at the energy range of ~ 0.1-10 GeV. Here we show that quasar-driven outflows generate relativistic protons that produce the missing component of the extragalactic $γ$-ray background and naturally match its spectral fingerprint, with a generic break above ~ 1 GeV. The associated $γ$-ray sources are too faint to be detected individually, explaining why they had not bee…
An analysis of ~19500 narrow (<200 km/s) CIV 1548.2,1550.8 absorbers in ~34000 Sloan Digital Sky Survey quasar spectra is presented. The statistics of the number of absorbers as a function of outflow-velocity shows that in approximately two-thirds of outflows, with multiple CIV absorbers present, absorbers are line-locked at the 500 km/s velocity separation of the CIV absorber doublet; appearing as 'triplets' in the quasar spectra. Line-locking is an observational signature of radiative line driving in outflowing material, where the successive shielding of 'clouds' of material in the outflow l…
GBT Detection of Polarization-dependent HI Absorption and HI Outflows in Local ULIRGs and Quasars
本文介绍了用罗伯特C。伯德格林班克望远镜（GBT）这些残骸是从类星体/ULIRG演化研究（QUEST）的超亮红外星系（ULIRG; L $_{8-1000 μm} > 10^{12}$ L $_\odot$）和类星体样本中选择的;我们的目标都是由活动星系核（AGN）控制的，并且是建议的ULIRG到类星体演化序列的后期阶段的样本。我们发现HI吸收（发射）的流行率是100%（29%）在ULIRG与HI检测，100%（88%）在FIR强类星体，和63%（100%）在FIR弱类星体。吸收功能与强大的中性外流，从主要驱动的恒星形成ULIRGs被驱动的类星体的活动星系核。在某些情况下，这些流出物的速度超过1500 km s $^{-1}$。出乎意料的是，我们在57%的光谱中发现了偏振相关的HI吸收（分别为88%和63%的FIR强和FIR弱类星体）。我们将这一结果归因于前景HI云对这些源的偏振连续辐射的吸收。在显示偏振光谱的类星体中，约有60%是射电强的，远高于在活动星系核中观测到的$\sim$ 10%。这种差异表明，射电喷流在塑造这些星系的环境方面起着重要作用。这些系统可能代表了一个过渡阶段，在丰富的气体合并到“成熟”的射电星系的演变。
Quasar feedback models often predict an expanding hot gas bubble which drives a galaxy-scale outflow. In many circumstances this hot gas radiates inefficiently and is therefore difficult to observe directly. We present an indirect method to detect the presence of a hot bubble using hydrostatic photoionization calculations of the cold (~10^4 K) line-emitting gas. We compare our calculations with observations of the broad line region, the inner face of the torus, the narrow line region (NLR), and the extended NLR, and thus constrain the hot gas pressure at distances 0.1 pc -- 10 kpc from the cen…
Broad absorption lines seen in some quasars prove the existence of ionized plasma outflows from the accretion disk. Outflows together with powerful jets are important feedback processes. Understanding physics behind BAL outflows might be a key to comprehend Galaxy Evolution as a whole. First radio-loud BAL quasar was discovered in 1997 and this discovery has opened new possibilities for studies of the BAL phenomena, this time on the basis of radio emission. However, information about the radio structures, orientation and age of BAL quasars is still very limited due to weak radio emission and s…
We study the geometry and the internal structure of the outflowing wind from the accretion disk of a quasar by observing multiple sightlines with the aid of strong gravitational lensing. Using Subaru/HDS, we performed high-resolution ($R$ $\sim$ 36,000) spectroscopic observations of images A and B of the gravitationally lensed quasar SDSS J1029+2623 (at $z_{em}$ $\sim$ 2.197) whose image separation angle, $θ$ $\sim$ 22$^{\prime\prime}\!\!$.5, is the largest among those discovered so far. We confirm that the difference in absorption profiles in the images A and B discovered by Misawa et al. (20…
Broad emission-line outflows of active galactic nuclei (AGNs) have been proposed for many years but are very difficult to quantitatively study because of the coexistence of the gravitationally-bound and outflow emission. We present detailed analysis of a heavily reddened quasar, SDSS J000610.67+121501.2, whose normal ultraviolet (UV) broad emission lines (BELs) are heavily suppressed by the Dusty Torus as a natural "Coronagraph", thus the blueshifted BELs (BBELs) can be reliably measured. The physical properties of the emission-line outflows are derived as follows: ionization parameter $U \sim…
