Related papers: Multiple Emission States in Active Galactic Nuclei
Active Galactic Nuclei (AGN), such as Seyfert galaxies, quasars, etc., show light variations in all wavelength bands, with various amplitude and in many time scales. The variations usually look erratic, not periodic nor purely random. Many…
Apart from viewing-dependent obscuration, intrinsic broad-line emission from active galactic nuclei (AGNs) follows an evolutionary sequence: Type $1 \to 1.2/1.5 \to 1.8/1.9 \to 2$ as the accretion rate onto the central black hole is…
Observations and simulations show that outflows in active galactic nuclei (AGN) contain gas in different phases. To understand their true impact on galaxy evolution, we advocate consistent and unbiased investigation of these multiphase…
The relationships between galaxies of intermediate stellar mass and moderate luminosity active galactic nuclei (AGNs) at 1<z<3 are investigated with the Galaxy Mass Assembly ultra-deep Spectroscopic Survey (GMASS) sample complemented with…
Active Galactic Nuclei (AGN) are energetic astrophysical sources powered by accretion onto supermassive black holes in galaxies, and present unique observational signatures that cover the full electromagnetic spectrum over more than twenty…
We discuss the theory and implementation of statistically rigorous fits to synchrotron self Compton models for datasets obtained from multi-wavelength observations of active galactic nuclei spectral energy distributions. The methods and…
In most galaxies, the fluxes of rotational H2 lines strongly correlate with star formation diagnostics (such as polycyclic aromatic hydrocarbons, PAH), suggesting that H2 emission from warm molecular gas is a minor byproduct of star…
Shocks in jets and hot spots of Active Galactic Nuclei (AGN) are one prominent class of possible sources of very high energy cosmic ray particles (above 10^18eV). Extrapolating their spectrum to their plausible injection energy from some…
Active galactic nuclei (AGN) are known as sources of high energy gamma-rays. The emission probably results from non-thermal radiation of relativistic jets belonging to the AGN. Earlier investigations of these processes have suggested that…
Active galactic nuclei (AGNs) exhibit complex variability across multiple wavelengths, reflecting diverse physical processes near their central engines. This work investigates the temporal variability of four AGNs Mrk~509, NGC~5548,…
The appearance of active galactic nuclei (AGN) depends so strongly on orientation that our current classification schemes are dominated by random pointing directions instead of more interesting physical properties. Light from the centers of…
Fluxes emitted at different wavebands from active galactic nuclei (AGNs) fluctuate at both long and short timescales. The variation can typically be characterized by a broadband power spectrum, which exhibits a red-noise process at high…
A sample of radio-loud active galactic nuclei (AGN) at 2cm is studied to test the isotropic distribution of radio sources in the sky and their uniform distribution in space. The sample is complete flux-density limits of 1.5Jy for positive…
We investigate faint radio emission from low- to high-luminosity Active Galactic Nuclei (AGN) selected from the Sloan Digital Sky Survey (SDSS). Their radio properties are inferred by co-adding large ensembles of radio image cut-outs from…
We employ hydrodynamical simulations using the moving-mesh code AREPO to investigate the role of energy and momentum input from Active Galactic Nuclei (AGN) in driving large-scale galactic outflows. We start by reproducing analytic…
We review the continuum emission of Active Galactic Nuclei (AGN) over the entire electromagnetic spectrum. After a brief historical introduction, we describe the main spectral properties of unobscured AGN, discussing the selection biases…
Extragalactic cosmic ray populations are important diagnostic tools for tracking the distribution of energy in nuclei and for distinguishing between activity powered by star formation versus active galactic nuclei (AGNs). Here, we compare…
Radio and gamma-ray emission from active galactic nuclei (AGN) are thought to share a common origin, related to the ejection phenomena in the vicinity of supermassive black holes. Thanks to its sensitivity, surveying capability, and broad…
We perform simulations to study the effects of active galactic nuclei (AGNs) radiation and wind feedback on the properties of slowly rotating accretion flow at parsec scale. We find that when only radiative feedback is considered, outflows…
Optical changing-look Active Galactic Nuclei (AGN) are a class of sources that change type within a short timescale of years or decades. This change is characterised by the appearance or disappearance of broad emission lines, often…