Related papers: Isotropic Luminosity Indicators in a Complete AGN …

We present a sample of twenty-one ROSAT bright active galactic nuclei (AGN), representing a range of spectral classes, and selected for follow-up snap-shot observations with XMM-Newton. The typical exposure was between 5-10 ks. The objects…

We selected 27244 nearby, red, giant early-type galaxies (RGEs) from the Sloan Digital Sky Survey (SDSS). In a large fraction (53%) of their spectra the [O III] emission line is detected, with an equivalent width (EW) distribution strongly…

We present a 5-8 micron analysis of the Spitzer-IRS spectra of 71 ultraluminous infrared galaxies (ULIRGs) with redshift z < 0.15, devoted to the study of the role of active galactic nuclei (AGN) and starbursts (SB) as the power source of…

We present the X-ray spectral analysis of two complementary sets of intermediate Seyfert galaxies (ISs). Analyzing X-ray data, we estimate the hydrogen abundance $N_H$ and test its connection with the [O III] luminosity acquired from…

We report MIPS photometry of 20 radio-loud quasars and galaxies at 24 and 70 um (and of five at 160 um). We combine this sample with additional sources detected in the far infrared by IRAS and ISO for a total of 47 objects, including 23…

We describe a complete volume limited sample of nearby active galaxies selected by their 14-195keV luminosity, and outline its rationale for studying the mechanisms regulating gas inflow and outflow. We describe also a complementary sample…

We present ROSAT HRI and ASCA observations of the well known ULIRG IRAS19254-7245 (the Superantennae). The object is not detected by ROSAT yielding a 3\sigma upper limit of L_x ~8x10^{41} erg/s in the 0.1-2 keV band. However, we obtain a…

Type 2 active galactic nuclei (AGN) show signatures of accretion onto a supermassive black hole through strong, high-ionization, narrow emission lines extended on scales of 100s to 1000s of parsecs, but they lack the broad emission lines…

We present new XMM-Newton observations of two luminous and high accretion-rate radio-quiet active galactic nuclei (AGNs) at z~2. Together with archival X-ray and rest-frame optical spectra of three sources with similar properties as well as…

This paper presents a comprehensive study of the X-ray properties of low-ionization nuclear emission-line regions (LINERs) and low-luminosity Seyfert galaxies based on observations obtained with ASCA. We analyzed data of 53 observations of…

The high-ionization mid-IR lines, excited in the Narrow Line Regions (NLR) of Active Galactic Nuclei (AGN), barely affected by stellar excitation and dust extinction, trace the AGN bolometric power. We used the complete 12 micron sample of…

We present mid-infrared data of a sample of 57 AGNs obtained with the instrument ISOCAM on board the satellite ISO. The images were obtained through the LW2 (6.75 microns) and LW7 (9.62 microns) filters. This is a new analysis of Clavel et…

8.4-GHZ radio imaging study of an optically selected sample of early type Seyfert galaxies; comparison of images taken at two epochs reveals possible variation in the nuclear radio flux density in five of them over a seven year period. It…

I present ASCA observations of IRAS00317-2142, the most luminous (Lx~10^43 erg s-1 0.1-2 keV) of the 'composite' class of galaxies. This enigmatic class of objects presents narrow-emission line optical spectra classifying these galaxies as…

Dust reprocesses the intrinsic radiation of active galactic nuclei (AGNs) to emerge at longer wavelengths. The observed mid-infrared (MIR) luminosity depends fundamentally on the luminosity of the central engine, but in detail it also…

We present medium resolution (R approx. 1500) ISO-SWS 2.4--45 micron spectra of a sample of 29 galaxies with active nuclei. This data set is rich in fine structure emission lines tracing the narrow line regions and (circum-)nuclear star…

The application of multi-wavelength selection techniques is crucial for discovering a complete and unbiased set of Active Galactic Nuclei (AGNs). Here, we select a sample of 72 AGN candidates in the Extended Groth Strip (EGS) using deep…

We present mid-IR observations of the prototypical Seyfert 2 galaxy NGC 1068 obtained with ISOCAM between 5 and 16micron. The proximity of this galaxy coupled with the spectro-imaging capabilities of the instrument allow us to separate the…

We present new, quasi-simultaneous hard X-ray and near-IR spectra of the ultraluminous infrared galaxy IRAS 05189-2524, and discuss them together with archival and literature data. The 1.9 Seyfert nucleus is Compton-thin. The near-IR broad…

We present the results of an optical spectroscopic survey designed to search for low-luminosity, "dwarf" Seyfert nuclei in a magnitude-limited sample of 486 bright, northern galaxies. Moderate-resolution spectra of exceptionally high…