相关论文: A Survey of Intrinsic Absorption in Active Galaxie…

We present a study of the intrinsic absorption lines in the ultraviolet spectra of Seyfert 1 galaxies. We find that the fraction of Seyfert 1 galaxies that show absorption associated with their active nuclei is more than one-half (10/17),…

Using the Far Ultraviolet Spectroscopic Explorer (FUSE) we have obtained 87 spectra of 57 low-redshift (z<0.15) active galactic nuclei (AGN). This sample comprises 53 Type 1 AGN and 4 Type 2. All the Type 1 objects show broad O VI 1034…

In a continuing survey of active galactic nuclei observed by the Far Ultraviolet Spectroscopic Explorer, we provide a deeper analysis of intrinsic absorption features found in 35 objects. Our survey is for low-redshift and…

We present far-ultraviolet spectra of the Seyfert 1.5 galaxy NGC 5548 obtained in 2000 June with the Far Ultraviolet Spectroscopic Explorer (FUSE). Our data span the observed wavelength range 915--1185 Angstroms at a resolution of 20 km/s.…

In a survey of the UV-brightest AGN using the Far Ultraviolet Spectroscopic Explorer (FUSE), we commonly find associated absorption in the O VI 1032,1038 resonance doublet. Of 34 Type I AGN observed to date with z < 0.15, 16 show detectable…

We report the results of a new analysis of the ROSAT Wide Field Camera (WFC) all-sky survey data, designed to detect extragalactic sources of extreme ultraviolet (EUV) radiation in regions of low Galactic N_H. We identify a total of 19…

We examine the variability in the intrinsic absorption in the Seyfert 1 galaxy Mrk 279 using three epochs of observations from the Far Ultraviolet Spectroscopic Explorer (FUSE) and two epochs of observations with the Space Telescope Imaging…

We present results from a coordinated FUSE, HST/STIS and Chandra campaign to study intrinsic UV and X-ray absorption in the outflow of the Seyfert 1 galaxy NGC 7469. Previous non-simultaneous observations of this outflow found two distinct…

Analysis of INTEGRAL Core Program and public Open Time observations performed up to April 2005 provides a sample of 62 active galactic nuclei in the 20-100 keV band above a flux limit of ~1.5x10^-11 erg/cm2/s. Most(42) of the sources in the…

We present far-ultraviolet spectra of the Seyfert 1 galaxy Mrk 509 obtained in 1999 November with the Far Ultraviolet Spectroscopic Explorer (FUSE). Our data span the observed wavelength range 915-1185 A at a resolution of ~20 km/s. The…

A fraction of active galactic nuclei do not show the classical Seyfert-type signatures in their optical spectra, i.e. they are optically "elusive". X-ray observations are an optimal tool to identify this class of objects. We combine new…

The Far Ultraviolet Spectroscopic Explorer (FUSE) has surveyed a large sample (> 100) of active galactic nuclei in the low redshift universe (z < 1). Its response at short wavelengths makes it possible to measure directly the EUV spectral…

$\require{mediawiki-texvc}$ We study accretion disk emission from eight Seyfert $1 - 1.5$ active galactic nuclei (AGN) using far ultra-violet ($1300-1800$ ${\AA}$) slit-less grating spectra acquired with AstroSat/UVIT. We correct for the…

We have analyzed archival \textit{Chandra} and \textit{XMM-Newton} data for two nearly complete homogeneously selected samples of type 2 Seyfert galaxies (Sy2s). These samples were selected based on intrinsic Active Galactic Nuclei (AGN)…

Analysis of INTEGRAL Core Program and public Open Time observations has recently provided a sample of 60 extragalactic sources selected in the 20-100 keV band above a flux of 1.5 10^-11 erg/cm2/s. As this band probes heavily obscured…

We present an analysis of the intrinsic UV absorption in the Seyfert 1 galaxy Mrk 279 based on simultaneous long observations with the Hubble Space Telescope (41 ks) and the Far Ultraviolet Spectroscopic Explorer (91 ks). To extract the…

We present ultraviolet spectra of the dwarf Seyfert 1 nucleus of NGC 4395, obtained with the Far Ultraviolet Spectroscopic Explorer (FUSE) and the Hubble Space Telescope's Space Telescope Imaging Spectrograph at velocity resolutions of 7 to…

We present new results for a sample of 33 narrow-lined UV-selected active galactic nuclei (AGNs), identified in the course of a spectroscopic survey for star-forming galaxies at z ~ 2-3. The rest-frame UV composite spectrum for our AGN…

We characterize the incidence of active galactic nuclei (AGNs) is 0.3 < z < 1 star-forming galaxies by applying multi-wavelength AGN diagnostics (X-ray, optical, mid-infrared, radio) to a sample of galaxies selected at 70-micron from the…

We present the far-ultraviolet spectrum of the Seyfert 1 galaxy 2MASX J21362313-6224008 obtained with the Far Ultraviolet Spectroscopic Explorer (FUSE). The spectrum features absorption from Galactic OVI at two velocities and redshifted HI…