相关论文: Testing the AGN unified model with simulated emiss…

A prediction of the classic active galactic nuclei (AGN) unification model is the presence of ionisation cones with different orientations depending on the AGN type. Confirmations of this model exist for present times, but it is less clear…

We present a study of an extended Lyman-alpha (Lya) nebula located in a known overdensity at z~2.38. The data include multiwavelength photometry covering the rest-frame spectral range from 0.1 to 250um, and deep optical spectra of the…

Some cosmological hydrodynamical simulations predict that outflows driven by active galactic nuclei (AGN) play a key role in powering the Ly$\alpha$ nebulae observed around high-redshift quasars. In such simulations, AGN feedback seeded as…

There exist conflicting observations on whether or not the environment of broad and narrow line AGN differ and this consequently questions the validity of the AGN unification model. The high spectroscopic completeness of the GAMA survey…

We present a comprehensive analysis of circumgalactic Lya nebulae around 59 unobscured and 26 obscured quasars at z=2-3, observed with the Keck Cosmic Web Imager (KCWI), to constrain the nature of active galactic nuclei (AGN) at cosmic…

Several `giant' Lyman-$\alpha$ (Ly$\alpha$) nebulae with extent $\gtrsim 300\,$kpc and observed Ly$\alpha$ luminosity of $\gtrsim 10^{44}\,{\rm erg}\,{\rm s}^{-1}\,{\rm cm}^{-2}\,{\rm arcsec}^{-2}$ have recently been detected, and it has…

Extended Ly$\alpha$ emission is commonly observed around star-forming galaxies, opening a window for probing the neutral hydrogen gas in the circumgalactic medium (CGM). In this paper, we develop a prescription of spherically symmetric CGM…

The unification of active galactic nuclei (AGN) is a model that has been difficult to test due to the lack of knowledge on the intrinsic luminosities of the objects. We present a test were we probe the model by statistical investigation of…

Ly$\alpha$ emission nebulae are ubiquitous around high-z galaxies and are tracers of the gaseous environment on scales out to >100 kpc. High-z radio galaxies (HzRGs, type-2 radio-loud quasars) host large scale nebulae observed in the…

The discovery of giant quasar Ly$\alpha$ nebulae at $z>2$ has opened up the possibility to directly study in emission the Circumgalactic and Intergalactic Medium (CGM/IGM). However, the resonant nature of the Ly$\alpha$ line and its…

In unified models, different types of active galaxy nuclei correspond to a single class of objects, where their observed differences are solely due to the different orientations of the obscuring material around the central inner regions.…

The orientation-based unification model of active galactic nuclei (AGNs) posits that the principle difference between obscured (Type 2) and unobscured (Type 1) AGNs is the line-of-sight into the central engine. If this model is correct than…

The detection of Ly$\alpha$ nebulae around $z\gtrsim 6$ quasars provides evidence for extended gas reservoirs around the first rapidly growing supermassive black holes. Observations of $z > 6$ quasars can be explained by cosmological models…

Predictions from current theories and simulations suggest that dual AGN systems are exceedingly rare at high redshifts. The intense radiation and powerful outflows from AGNs regulate star formation, heat the interstellar medium, and drive…

The recent discovery of enormous Ly$\alpha$ nebulae (ELANe), characterized by physical extents $>200$ kpc and Ly$\alpha$ luminosities $>10^{44}$ erg s$^{-1}$, provide a unique opportunity to study the intergalactic and circumgalactic medium…

We select a sample of 90 obscured (type2) AGN with 1.45<z<3.05 from the zCOSMOS-deep galaxy sample by 5 sigma-detection of the high-ionization CIV {\lambda}1549 narrow emission line. The presence of this feature in a galaxy spectrum is…

Active galactic nuclei (AGN) are thought to play a critical role in shaping galaxies, but their effect on the circumgalactic medium (CGM) is not well studied. We present results from the COS-AGN survey: 19 quasar sightlines that probe the…

Recent wide-field integral field spectroscopy has revealed the detailed properties of high redshift Lyman-alpha (Lya) nebulae, most often targeted due to the presence of an active galactic nucleus (AGN). Here, we use VLT/MUSE to resolve the…

Motivated by the claimed detection of a large population of faint active galactic nuclei (AGN) at high redshift, recent studies have proposed models in which AGN contribute significantly to the z > 4 H I ionizing background. In some models,…

Circumgalactic Lyman-alpha (Ly$\alpha$) nebulae are gaseous halos around galaxies exhibiting luminous extended Ly$\alpha$ emission. This work investigates Ly$\alpha$ nebulae from deep imaging of $\sim12~\mathrm{deg}^2$ sky, targeted by the…