Resolving the C IV and Mg II Absorption in NGC 4151 (2009)
Abstract. Observations of the C iv and Mg ii absorption lines in the Seyfert 1 galaxy NGC 4151 obtained with the GHRS in October 1994 are presented. The data from the STScI archive show multiple...
Variable Intrinsic Absorption in Mrk 279 (2008)
Scott, Jennifer E., Arav, Nahum, Gabel, Jack R., Kriss, Gerard A., Quijano, Jessica Kim, Kaastra, Jelle S., ...
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...
Gerard A. Kriss, Arthur F. Davidsen, Wei Zheng, Jeffrey W. Kruk, Brian R. Espey, Up To \theta
We observed NGC 4151 on six separate occasions at intervals of one to three days using the Hopkins Ultraviolet Telescope during the flight of Astro-2 aboard the space shuttle Endeavour in March 1995....
CHEMICAL ABUNDANCES IN AN AGN ENVIRONMENT: X-RAY/UV CAMPAIGN ON THE MARKARIAN 279 OUTFLOW (2007)
Arav, Nahum, Gabel, Jack R., Korrista, Kirk T., Kaastra, Jelle S., Kriss, Gerard A., Behar, Ehud, ...
We present the first reliable determination of chemical abundances in an active galactic nucleus (AGN) outflow. The abundances are extracted from the deep and simultaneous Far Ultraviolet...
HUBBLE SPACE TELESCOPE ULTRAVIOLET SPECTROSCOPY OF 14 LOW-REDSHIFT QUASARS (2007)
Ganguly, Rajib, Brotherton, Michael S., Arav, Nahum, Heap, Sara R., Wisotzki, Lutz, Aldcroft, Thomas L., ...
We present low-resolution ultraviolet spectra of 14 low-redshift (zem ≤ 0:8) quasars observed with the Hubble Space Telescope STIS as part of a Snapshot project to understand the relationship...
Chemical Abundances in AGN Environment: X-Ray/UV Campaign on the MRK 279 Outflow (2006)
Arav, Nahum, Gabel, Jack R., Korista, Kirk T., Kaastra, Jelle S., Kriss, Gerard A., Behar, Ehud, ...
We present the first reliable determination of chemical abundances in an AGN outflow. The abundances are extracted from the deep and simultaneous FUSE and HST/STIS observations of Mrk 279. This data...
Hubble Space Telescope Ultraviolet Spectroscopy of Fourteen Low-Redshift Quasars (2006)
Ganguly, Rajib, Brotherton, Michael S., Arav, Nahum, Heap, Sara R., Wisotzki, Lutz, L. Aldcroft, Thomas, ...
We present low-resolution ultraviolet spectra of 14 low redshift (z em < 0.8) quasars observed with HST/STIS as part of a Snap project to understand the relationship between quasar outflows and...
Hubble Space Telescope Ultraviolet Spectroscopy of Fourteen Low-Redshift Quasars (2006)
Ganguly, Rajib, Brotherton, Michael S., Arav, Nahum, Heap, Sara R., Wisotzki, Lutz, Aldcroft, Thomas L., ...
We present low-resolution ultraviolet spectra of 14 low redshift (z
Scott, Jennifer E., Kriss, Gerard A., Lee, Julia C., Quijano, Jessica Kim, Brotherton, Michael, Canizares, Claude R., ...
We present simultaneous X-ray, far-ultraviolet, and near-ultraviolet spectra of the Seyfert 1 galaxy NGC 7469 obtained with the Chandra X-Ray Observatory, the Far Ultraviolet Spectroscopic Explorer,...
Gabel, Jack R., Arav, Nahum, Kaastra, Jelle S., Kriss, Gerard A., Behar, Ehud, Costantini, Elisa, ...
We present an analysis of the intrinsic UVabsorption in the Seyfert 1 galaxy Mrk 279 based on simultaneous long observations with the Hubble Space Telescope (41 ks) and the Far Ultraviolet...
Gabel, Jack R., Arav, Nahum, Kaastra, Jelle S., Kriss, Gerard A., Behar, Ehud, Costantini, Elisa, ...
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...
FUSE and the Astrophysics of AGN and QSOs (2004)
The high spectral resolution and sensitivity of FUSE have enabled far-ultraviolet studies of AGN and QSOs that are a natural complement to observations using HST, Chandra, and XMM-Newton. Through...
Quasars and the Big Blue Bump (2004)
Shang, Zhaohui, Brotherton, Michael S., Green, Richard F., Kriss, Gerard A., Scott, Jennifer, Quijano, Jessica Kim, ...
We investigate the ultraviolet-to-optical spectral energy distributions (SEDs) of 17 active galactic nuclei (AGNs) using quasi-simultaneous spectrophotometry spanning 900-9000 Angstrom (rest frame)....
A Composite Extreme Ultraviolet QSO Spectrum from the Far Ultraviolet Spectroscopic Explorer (2004)
Scott, Jennifer E., Kriss, Gerard A., Brotherton, Michael, Green, Richard F., Hutchings, John, Shull, J. Michael, ...
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...
X-ray/UV Campaign on the Mrk 279 AGN Outflow: Constraining Inhomogeneous Absorber Models (2004)
Arav, Nahum, Kaastra, Jelle, Kriss, Gerard A., Korista, Kirk T., Gabel, Jack, Proga, Daniel
We investigate the applicability of inhomogeneous absorber models in the formation of AGN outflow absorption-troughs. The models we explore are limited to monotonic gradients of absorbing column...
A Far-Ultraviolet Spectroscopic Survey of Low-Redshift AGN (2004)
Using the Far Ultraviolet Spectroscopic Explorer (FUSE) we have obtained 87 spectra of 57 low-redshift (z
UV and X-ray Observations of Mass Outflows in AGN (2004)
More than half of all low-redshift AGN exhibit UV and X-ray absorption by highly ionized gas. The observed UV and X-ray absorption lines are almost always blue-shifted at velocities of hundreds of...
A Composite Extreme Ultraviolet QSO Spectrum from FUSE (2004)
Scott, Jennifer E., Kriss, Gerard A., Brotherton, Michael, Green, Richard F., Hutchings, John, Shull, J. Michael, ...
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...
Scott, Jennifer E., Kriss, Gerard A., Lee, Julia C., Arav, Nahum, Ogle, Patrick, Roraback, Kenneth, ...
We present a study of the intrinsic X-ray and far-ultraviolet absorption in the Seyfert 1.5 galaxy Markarian 279 using simultaneous observations from the Chandra X-ray Observatory, the Space...
Shull, J. Michael, Tumlinson, Jason, Giroux, Mark L., Kriss, Gerard A., Reimers, Dieter
We provide an in-depth analysis of the He II and H I absorption in the intergalactic medium (IGM) at redshifts z = 2.3-2.9 toward HE 2347-4342, using spectra from the Far Ultraviolet Spectroscopic...
The Ionized Gas and Nuclear Environment in NGC 3783 II. Averaged HST/STIS and FUSE Spectra (2002)
Gabel, Jack R., Crenshaw, D. Michael, Kraemer, Steven B., Brandt, W. N., George, Ian M., Hamann, Frederick W., ...
We present observations of the intrinsic absorption in the Seyfert 1 galaxy NGC 3783 obtained with the STIS/HST and FUSE. We have coadded multiple STIS and FUSE observations to obtain a high S/N...
Warm Absorbers in AGN: A Multi-Temperature Wind (2001)
Krolik, Julian H., Kriss, Gerard A.
Although soft X-ray absorption features in AGN were discovered almost ten years ago, the nature and location of the gas creating them has remained controversial. Guided by the results of recent...
FUSE Observations of Warm Absorbers in AGN (2001)
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...
Far-Ultraviolet Spectra of AGN: First Results from FUSE (2000)
Composite spectra derived from HST observations of moderate redshift (z~1) quasars show that the peak of the spectral energy distribution is at ~1000 A, and that the ionizing continuum falls off...
Kriss, Gerard A., Peterson, Bradley M., Crenshaw, D. Michael, Zheng, Wei
From 1996 June 10 to 1996 July 29 the International AGN Watch monitored the Seyfert 1 galaxy NGC 7469 using IUE, RXTE, and a network of ground-based observatories. On 1996 June 18, in the midst of...
Spatially Resolved Hopkins Ultraviolet Telescope Spectra of NGC 1068 (1999)
Grimes, John P., Kriss, Gerard A., Espey, Brian R.
We present spatially resolved far-UV spectra (912-1840 A) of NGC 1068 obtained using the Hopkins Ultraviolet Telescope (HUT) during the March 1995 Astro-2 mission. Three spectra of this prototypical...
The Very Highly Ionized Broad Absorption Line System of the QSO SBS1542+541 (1998)
Telfer, Randal C., Kriss, Gerard A., Zheng, Wei, Davidsen, Arthur F., Green, Richard F.
We have analyzed the broad absorption line system of the bright (V=16.5) high-redshift (z=2.361) QSO SBS1542+541 using UV spectra from the HST FOS along with optical data from the MMT and the Steward...
M87: A Misaligned BL LAC? (1997)
Tsvetanov, Zlatan I., Hartig, George F., Ford, Holland C., Dopita, Michael A., Kriss, Gerard A., Pei, Yichuan C., ...
The nuclear region of M87 was observed with the Faint Object Spectrograph (FOS) on the Hubble Space Telescope (HST) at 6 epochs, spanning 18 months, after the HST image quality was improved with the...
The He II Opacity of the Lyman-alpha Forest and the Intergalactic Medium (1997)
Zheng, Wei, Davidsen, Arthur F., Kriss, Gerard A.
Based on the empirical formulas governing the distribution of Ly-a forest absorption, we use a Monte-Carlo technique to calculate the average HeII optical depth produced by these forest lines. A...
Resolving the C IV and Mg II Absorption in NGC 4151 (1996)
Observations of the C IV and Mg II absorption lines in the Seyfert 1 galaxy NGC 4151 obtained with the GHRS in October 1994 are presented. The data from the STScI archive show multiple broad and...
Observable Properties of X-ray Heated Winds in AGN: Warm Reflectors and Warm Absorbers (1995)
Krolik, Julian H., Kriss, Gerard A.
When an AGN is obscured, the warm reflecting gas nearby can be seen by a combination of bremsstrahlung, intrinsic line emission, and reflection of the nuclear continuum, both by electron scattering...