相关论文: Long Term Reverberation Mapping of Iron Coronal Li…

We investigated by means of MUSE/VLT observations the true size of the coronal line region (CLR) in a local sample of nine active galactic nuclei known for displaying prominent coronal emission. Our analysis show that the CLR is extended…

(Abridge) The relationship between coronal line (CL) emission and nuclear activity in active galactic nuclei (AGNs) is analyzed, for the first time, based on NIR spectra. The 8 CLs studied, of Si, S, Fe, Al and Ca elements and corresponding…

We present the first intensive study of the variability of the near-infrared coronal lines in an active galactic nucleus (AGN). We use data from a one-year long spectroscopic monitoring campaign with roughly weekly cadence on NGC 5548 to…

We examine the long-term history of the optical spectrum of the extremely variable Active Galactic Nucleus (AGN) MKN 110. By combining various archival data with new data, we cover an unprecedented long period of $\sim$30 years (1987 -…

We present reverberation mapping measurements for the prominent ultraviolet broad emission lines of the active galactic nucleus Mrk817 using 165 spectra obtained with the Cosmic Origins Spectrograph on the Hubble Space Telescope. Our…

Short X-ray reverberation lags are seen across a broad Fe-K energy band in more than twenty active galactic nuclei (AGNs). This broad iron line feature in the lag spectrum is most significant in super-Eddington sources such as Ark 564…

Significant variability in broad emission line strengths of active galactic nuclei (AGN) over months to years has been observed, often accompanied by intrinsic continuum changes. Such spectral variability challenges the traditional AGN…

Many AGN exhibit a highly variable luminosity. Some AGN also show a pronounced time delay between variations seen in their optical continuum and in their emission lines. In effect, the emission lines are light echoes of the continuum. This…

High cadence, high quality observations of active galactic nuclei (AGN) clearly show continuum variations with lags, relative to the shortest observed variable UV continuum, that increase with wavelength ("lag spectra"). These have been…

The fundamental nature and extent of the coronal line region (CLR), which may serve as a vital tracer for Active Galactic Nucleus (AGN) activity, remain unresolved. Previous studies suggest that the CLR is produced by AGN-driven outflows…

Continuum reverberation mapping probes the sizescale of the optical continuum-emitting region in active galactic nuclei (AGN). Through 3 years of multiwavelength photometric monitoring in the optical with robotic observatories, we perform…

Coronal-Line Forest Active Galactic Nuclei (CLiF AGN) are characterized by strong high-ionization lines, which contrast to what is found in most AGNs. Here, we carry out a multiwavelength analysis aimed at understanding the physical…

Spectral energy distributions (SEDs) from X-ray to far-infrared (FIR) wavelengths are presented for a sample of 1246 X-ray luminous active galactic nuclei (AGN; $L_{0.5-10\rm{keV}}>10^{43}$ erg s$^{-1}$), with $z_{\rm{spec}}<1.2$, selected…

We present the Granger causality (GC) test for the X-ray reverberation analysis of Active Galactic Nuclei (AGN). If the light curves in the continuum-dominated band help predict (Granger cause) those dominated by reflection, the Granger…

We present the result of a study of the X-ray emission from the Galactic Centre (GC) Molecular Clouds (MC) within 15 arcmin from Sgr A*. We use XMM-Newton data (about 1.2 Ms of observation time) spanning about 8 years. The MC spectra show…

An intensive reverberation mapping campaign on the Seyfert 1 galaxy Mrk817 using the Cosmic Origins Spectrograph (COS) on the Hubble Space Telescope (HST) revealed significant variations in the response of the broad UV emission lines to…

"Changing-look active galactic nuclei" (CLAGNs) are known to change their apparent types between types 1 and 2, usually accompanied by a drastic change in their luminosity on timescales of years. However, it is still unclear whether…

VLT and NTT spectra are used to examine the nuclear and extended coronal line emission in a sample of well-known Seyfert 1 and 2 galaxies. The excellent spatial resolution obtained with VLT allowed us to map [SiVI] 1.963 $\mu$m and [SiVII]…

We analyze the long-term evolution of the fluxes of six active galactic nuclei (AGN) - 0923+392, 3C 111, 3C 273, 3C 345, 3C 454.3, and 3C 84 - in the frequency range 80-267 GHz using archival calibration data of the IRAM Plateau de Bure…

Forbidden coronal lines has traditionally called the attention due to the high-energy photons required for their production (IP $>$100~eV, where IP is the ionisation potential of the transitions that originate the line). As such, they are…