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Abstract: We have analyzed the radio light curves of the Seyfert galaxy III Zw 2 at 22 and 37GHz taken from the database of Metsähovi Radio Observatory, and found evidence of quasi-periodic activity. The light curves show great activity, with very complicated non-sinusoidal variations. Period of was consistently identified by three methods: the Jurkevich method, the power spectrum intensity estimation method and the discrete correlation function method. The variability period of about 5.14yr in III Zw 2 is caused most likely by the helical motion of the jet. [Copyright &y& Elsevier]

Abstract: The James Webb Space Telescope (JWST), due to launch in 2014, shall provide an unprecedented wealth of information in the near and mid-infrared wavelengths, thanks to its high-sensitivity instruments and its 6.5m primary mirror, the largest ever launched into space. NIRSpec and MIRI, the two spectrographs onboard JWST, will play a key role in the study of the spectral features of Active Galactic Nuclei in the 0.6–28μm wavelength range. This article aims at presenting an overview of the possibilities provided by these two instruments, in order to prepare the astronomical community for the JWST era. [Copyright &y& Elsevier]

Abstract: By means of a batch of low-redshift spectral data of AGNs taken from the SDSS, an automated K-nearest neighbor method is developed to classify AGNs into two types: broad-line and narrow-line AGNs. According to the different characteristics of emission lines of broad-line and narrow-line AGNs, the spectral wavebands containing the Hβ, [OIII], Hα and [NII] emission lines are used separately or in combination in the classification. experiment. The results show that the best results are obtained when only the wavebands of H and [NII] are used, and that for a training set of size 1000 and a testing set of 3313, we can achieve a speed of 32.89 single classifications per second. It is demonstrated that, where the typical spectral features are sufficiently exploited, the automated classification method is feasible for the spectra of AGNs in largescale spectral surveys and provides a fast and straightforward alternative to classification schemes based on using the FWHM values of emission lines or the line strength ratio diagnostic diagrams. [Copyright &y& Elsevier]

Abstract: We present preliminary results of an interferometric study of the water megamaser in the merger system Arp 299. This system is composed of two main sources: IC 694 and NGC 3690. There is clear evidence that most of the water maser emission is associated with the nucleus of the latter, confirming the presence of an optically obscured AGN as previously suggested by X-ray observations. Furthermore, emission arises from the inner regions of IC 694, where an OH megamaser is also present. The velocity of the water maser line is blueshifted w.r.t. the optically determined systemic velocity and is consistent with that of the OH megamaser line. This finding might then indicate that both masers are associated with the same (expanding) structure and that, for the first time, strong 22GHz H2O and 1.67GHz OH maser emission has been found to coexist. [Copyright &y& Elsevier]

Abstract: We investigate a corona coupled with an underlying disk through magnetic and radiation fields. By studying the interaction between the corona and disk, we determine the fraction of accretion energy dissipated in the corona for a given black-hole mass and accretion rate. This allows us to calculate the emergent spectra through Monte Carlo simulations. The spectra are then determined as functions of black-hole mass and accretion rate. We find two types of solutions corresponding to hard spectrum and soft spectrum. In the hard-spectrum solution, the accretion energy is dominantly dissipated in the corona. The hard X-ray spectral indices are the same for different accretion rate, i.e., α ∼1.1. In the soft-spectrum solution, the accretion energy is mainly dissipated in the disk. The spectra are dominated by the disk radiation peaked in UV and soft X-rays. For low-luminosity systems (L ⩽0.2L Edd), there exists only the solution of hard spectra; while for high-luminosity systems (L ⩾0.8L Edd), there exist both solutions of hard and soft spectra. The hard spectra are close to the observed spectra in Seyfert galaxies and radio-quiet QSOs. [Copyright &y& Elsevier]

Abstract: Short-term variability of X-ray spectra has been reported for several Active Galactic Nuclei. Significant X-ray flux variations are observed within time scales down to 104–105 s. We discuss short variability time scales in the framework of the X-ray flare model, which assumes the release of a large hard X-ray flux above a small portion of the accretion disk. The resulting observed X-ray spectrum is composed of the primary radiation as well as a reprocessed/Compton reflection component that we model performing numerical radiative transfer simulations. We conduct Monte-Carlo simulations of large flare distributions across the disk including relativistic corrections of the observed radiation and discuss general implications on AGN spectra and their variability. [Copyright &y& Elsevier]

Abstract: We will present first results of ESO-VLT AO-assisted integral-field spectroscopy of a sample of X-ray bright AGN with redshifts of 0.04< z <1. We constructed this sample by cross-correlating the SDSS and ROSAT surveys and utilizing typical AO constraints. This sample allows for a detailed study of the NIR properties of the nuclear and host environments with high spectral resolution on the 100pc scale. These objects can then be compared directly to the local (z <0.01) galaxy populations (observed without AO) at the same linear scale. As a current example, we will present observations of the z =0.034 Seyfert 1.8 galaxy Mrk 609 with the new AO-assisted integral-field spectrometer SINFONI at the VLT. The successful observations show, that in the future – while having observed more objects – we will be able to determine the presence, frequency and importance of nuclear bars and/or circum-nuclear star forming rings in these objects and address the question of how these X-ray luminous AGN and their hosts are linked to optically/UV-bright QSOs, low-z QSOs/radio galaxies, or ULIRGs. [Copyright &y& Elsevier]

Abstract: Although the existence of asymmetrical profile of [OIII]λ5007 has been discovered for ages, its filiation and physics are poorly understood. Two new spectra of I ZWI taken on November 16, 2001 and on December 3, 2002 were compared with the spectra taken by BG92. Following results are obtained. (1) The certain variations of broad [OIII] during about 10 years separating the observations are identified. The inferred length scale of broad [OIII] emitting region ranges from 0.3 to 3pc. By assuming a Keplerian motion in line emitting region, the material emitting broad [OIII] is likely to be located at the transient emission line region, between BLR and NLR. (2) We find a positive relation between the FeII emission and flux of Hβ (or continuum). On the other hand, the parameter RFe decreases with ionizing continuum marginally. (3) We detect a low ionized NLR in I ZWI, because of the low flux ratios [OIII]n/Hβn (∼1.7). [Copyright &y& Elsevier]

Abstract: We present results from the analysis of an XMM-Newton observation of the Seyfert 1 galaxy NGC 7469, the first high resolution X-ray spectrum of this source. The Reflection Grating Spectrometer (RGS) spectrum has several narrow absorption and emission lines of O, N, C and Ne, originating from gas at a range of ionisation parameters, from logξ∼1.6 to logξ∼−2 (where ξ has the units ergcms−1). We demonstrate that the ionisation state of the warm emitter is consistent with that of the high-ionisation phase of the warm absorber, and compare the warm absorber in this object with those in other sources. [Copyright &y& Elsevier]

We present initial results from a follow-up of the 9C survey, complete to 25 mJy at 15 GHz, designed to assemble and investigate a sample of young radio sources. We have made radio continuum maps of 111 sources at frequencies spanning 1.4–43 GHz, and classified them according to their radio size and spectral index between 1.4 and 4.8 GHz. We find that selection at 15 GHz is twice as efficient at picking Gigahertz Peaked Spectrum (GPS) sources as selection at ∼5 GHz. Optical follow-up has now begun; imaging of GPS and compact steep spectrum sources suggests that a significant fraction of the host galaxies have close companions or disturbed morphologies. [Copyright &y& Elsevier]

We summarise the properties of the absorbing haloes around two high-redshift radio galaxies studied with the VLT-UVES echelle spectrograph. The absorbers in 0943−242 (z=2.92) exhibit little further structure compared with previous data—the main absorber still has N(HI)≃1019 cm−2—reinforcing the picture in which the absorbing gas occupies a smooth shell beyond the emission line halo. In 0200+015 (z=2.23) the main absorber now splits into two spatially-resolved systems with N(HI)≃4×1014 cm−2, one of which has strong CIV absorption, implying a metallicity of Z≃10 Z◎. We explain the differences between the two sources with an evolutionary scenario, invoking interaction with the expanding radio source and metal enrichment via a starburst superwind. [Copyright &y& Elsevier]

Narrowband Ly α imaging has been carried out around eight radio galaxies at 2 to search for (proto-)cluster galaxies at the same redshift. Subsequent spectroscopy has led to the discovery of six protoclusters at redshifts z=2.2, 2.9, 2.9, 3.1, 3.2 and 4.1, with velocity dispersions between 300 km s−1 and 1000 km s−1. The estimated masses are in the range 1014–1016 M⊙, comparable to the mass of present day rich clusters of galaxies. [Copyright &y& Elsevier]

Keck LRISp optical spectropolarimetry and VLT ISAAC NIR spectroscopy of an overlapping sample of z∼2.5 radio galaxies has provided a set of uniquely high quality spectra stretching from Ly α to Hα. The measurement of emission and absorption line strengths, continuum polarization and SED allow us to quantify the various emission and scattering mechanisms that comprise the observed spectra. We identify this epoch as critical in the chemical evolution of massive spheroids and show that, while star formation must be very active, most of the UV/optical radiation we see from these luminous sources derives from the AGN. [Copyright &y& Elsevier]

Powerful radio galaxies often display enhanced optical/UV continuum emission and extended emission line regions, elongated and aligned with the radio jet axis. The expansion of the radio source strongly affects the gas clouds in the surrounding IGM, and the kinematic and ionization properties of the extended emission line regions display considerable variation over the lifetime of individual sources, as well as with cosmic epoch. We present the results of deep rest-frame UV and optical imaging and UV spectroscopy of high redshift 6C radio galaxies. The interdependence of the host galaxy and radio source properties are discussed, considering: (i) the relative contribution of shocks associated with the expanding radio source to the observed emission line gas kinematics, and their effect on the ionization state of the gas; (ii) the similarities and differences between the morphologies of the host galaxies and aligned emission for a range of radio source powers; and (iii) the influence of radio power on the strength of the observed alignment effect. [Copyright &y& Elsevier]

Low-luminosity AGNs (LLAGNs) are a very important class of sources since they occur in a significant fraction of local galaxies. Their spectra differ significantly from the canonical luminous AGNs, most notably by the absence of the ‘big blue bump’. Up until now there is no model which can explain the spectra of LLAGNs. Taking NGC 4258 as an example, we propose a coupled jet-disk model for some LLAGNs. [Copyright &y& Elsevier]