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Constraining the AGN Contribution in a Multiwavelength Study of Seyfert Galaxies
M. Meléndez, S. B. Kraemer, H. R. Schmitt +4
We have studied the relationship between the high- and low-ionization [O IV] lambda 25.89 micron, [Ne III] lambda 15.56 micron and [Ne II] lambda 12.81 micron emission lines with t…
New Indicators for AGN Power: The Correlation Between [O IV] lambda 25.89 micron and Hard X-ray Luminosity for Nearby Seyfert Galaxies
M. Meléndez, S. B. Kraemer, B. K Armentrout +7
We have studied the relationship between the [O IV] lambda 25.89 micron emission line luminosities, obtained from Spitzer spectra, the X-ray continua in the 2-10 keV band, primaril…
Mass Outflow from the Nucleus of the Seyfert 1 Galaxy NGC 4151
D. M. Crenshaw, S. B. Kraemer
We present an analysis of UV and optical spectra of NGC 4151 obtained at high spectral and angular resolutions with the Hubble Space Telescope's (HST's) Space Telescope Imaging Spe…
The Host Galaxies of Narrow-Line Seyfert 1s: Nuclear Dust Morphology and Starburst Rings
R. P. Deo, D. M. Crenshaw, S. B. Kraemer
We present a study of the nuclear morphology of a sample of narrow- and broad-line Seyfert 1 galaxies (NLS1's and BLS1's) based on broad-band images in the Hubble Space Telescope a…
Kinematics of the Narrow-Line Region in the Seyfert 2 Galaxy NGC 1068: Dynamical Effects of the Radio Jet
V. Das, D. M. Crenshaw, R. P. Deo +1
We present a study of high-resolution long-slit spectra of the narrow-line region (NLR) in NGC 1068 obtained with the Space Telescope Imaging Spectrograph (STIS) aboard The Hubble…
The Ionized Gas and Nuclear Environment in NGC 3783 V. Variability and Modeling of the Intrinsic Ultraviolet Absorption
J. R. Gabel, S. B. Kraemer, D. M. Crenshaw +13
We present results on the location, physical conditions, and geometry of the outflow in the Seyfert 1 galaxy NGC 3783 from a study of the variable intrinsic UV absorption. Based on…
Mapping the Kinematics of the Narrow-Line Region in the Seyfert Galaxy NGC 4151
V. Das, D. M. Crenshaw, J. B. Hutchings +6
Using The Hubble Space Telescope's Space Telescope Imaging Spectrograph HST's STIS, observations of the OIII emission from the narrow-line region (NLR) of NGC 4151 were obtained an…
Probing the Ionizing Continuum of Narrow-Line Seyfert 1 Galaxies. I.Observational Results
M. Dietrich, D. M. Crenshaw, S. B. Kraemer
We present optical spectra and emission-line ratios of 12 Narrow-Line Seyfert 1 (NLS1) galaxies that we observed to study the ionizing EUV continuum. A common feature in the EUV co…
Simultaneous X-ray and UV spectroscopy of the Seyfert 1 galaxy NGC 5548.II. Physical conditions in the X-ray absorber
K. C. Steenbrugge, J. S. Kaastra, D. M. Crenshaw +8
We present the results from a 500 ks Chandra observation of the Seyfert 1 galaxy NGC 5548. We detect broadened emission lines of O VII and C VI in the spectra, similar to those obs…
Physical Conditions in the Narrow-Line Region of Markarian 3. I. Observational Results
Nicholas R. Collins, Steven B. Kraemer, D. Michael Crenshaw +3
We use Hubble Space Telescope/Space Telescope Imaging Spectrograph (HST/STIS) longslit low-resolution spectroscopy from 1150A to 10,300A to study the physical conditions in the nar…
Complex X-ray Absorption and the Fe Kalpha Profile in NGC 3516
T. J. Turner, S. B. Kraemer, I. M. George +2
We present data from simultaneous Chandra, XMM-Newton and BeppoSAX observations of the Seyfert 1 galaxy NGC 3516, taken during 2001 April and Nov. We have investigated the nature o…
Simultaneous X-ray and Ultraviolet spectroscopy of the Seyfert galaxy NGC 5548. III. X-ray time variability
J. S. Kaastra, K. C. Steenbrugge, D. M. Crenshaw +8
The Seyfert 1 galaxy NGC 5548 was observed for a week by Chandra using both the HETGS and LETGS spectrometers. In this paper we study the time variability of the continuum radiatio…
On the Relationship Between the Optical Emission-Line and X-ray Luminosities in Seyfert 1 Galaxies
S. B. Kraemer, I. M. George, D. M. Crenshaw +1
We have explored the relationship between the [O III] 5007 and the 2--10 keV luminosities for a sample of Broad- and Narrow-Line Seyfert 1 galaxies (BLSy1 and NLSy1, respectivel…
The Effects of Low-Temperature Dielectronic Recombination on the Relative Populations of the Fe M-Shell States
S. B. Kraemer, G. J. Ferland, J. R. Gabel
We examine the effects of low-temperature, or , dielectronic recombination (DR) on the ionization balance of the Fe M-Shell (Fe IX through Fe XVI). Since rates…
The Host Galaxies of Narrow-Line Seyfert 1s: Evidence for Bar-Driven Fueling
D. M. Crenshaw, S. B. Kraemer, J. R. Gabel
We present a study of the host-galaxy morphologies of narrow- and broad-line Seyfert 1 galaxies (NLS1s and BLS1s) based on broad-band optical images from the Hubble Space Telescope…
The Ionized Gas and Nuclear Environment in NGC 3783 III. Detection of a Decreasing Radial Velocity in an Intrinsic UV Absorber
J. R. Gabel, D. M. Crenshaw, S. B. Kraemer +14
We report an intrinsic absorber with decreasing outflow velocity in the Seyfert 1 galaxy NGC 3783. This is the first detection of a change in radial velocity in an outflow associat…
Elemental Abundances in NGC 3516
T. J. Turner, S. B. Kraemer, R. F. Mushotzky +2
We present RGS data from an XMM-Newton observation of the Seyfert 1 galaxy NGC 3516, taken while the continuum source was in an extreme low state. The spectrum shows numerous emiss…
Simultaneous UV and X-ray Spectroscopy of the Seyfert 1 Galaxy NGC 5548. I. Physical Conditions in the UV Absorbers
D. M. Crenshaw, S. B. Kraemer, J. R. Gabel +9
We present new UV spectra of the nucleus of the Seyfert 1 galaxy NGC 5548, which we obtained with the Space Telescope Imaging Spectrograph at high spectral resolution, in conjuncti…
The Kinematics and Physical Conditions of the Ionized Gas in Markarian 509. I. Chandra High-Energy Grating Spectroscopy
T. Yaqoob, B. McKernan, S. B. Kraemer +4
We observed the Seyfert 1 galaxy Mrk 509 simultaneously with Chandra/HETG, HST/STIS and RXTE. We measure strong absorption lines from He-like Ne and Mg, and from H-like N, O, and N…
The Kinematics and Physical Conditions pf the Ionized Gas in Markarian 509. II. STIS Echelle Observations
S. B. Kraemer, D. M. Crenshaw, T. Yaqoob +5
We present observations of the UV absorption lines in the luminous Seyfert 1 galaxy Mrk 509, obtained with the medium resolution (lambda/Delta-lambda ~ 40,000) echelle gratings of…
Balmer and He I absorption in the nuclear spectrum of NGC 4151
J. B. Hutchings, D. M. Crenshaw, S. B. Kraemer +4
Spectra taken with the Space Telescope Imaging Spectrograph (STIS) allow accurate location and extraction of the nuclear spectrum of NGC 4151, with minimal contamination by extende…
The Spectral Energy Distribution of the Seyfert galaxy Ton S180
T. J. Turner, P. Romano, S. B. Kraemer +14
We present spectral results from a multi-satellite, broad-band campaign on the Narrow-line Seyfert 1 galaxy Ton S180 performed at the end of 1999. We discuss the spectral-energy di…
On the Nature of Intrinsic Absorption in Reddened Seyfert 1 Galaxies
D. M. Crenshaw, S. B. Kraemer
We discuss the origin of the ``dusty lukewarm absorber'', which we previously identified in the reddened Seyfert 1 galaxies NGC 3227 and Akn 564. This absorber is characterized by…
STIS Echelle Observations of the Intrinsic UV Absorption in the Seyfert 1 Galaxy NGC 3783
S. B. Kraemer, D. M. Crenshaw, J. R. Gabel
We present observations of the UV absorption lines in the Seyfert 1 galaxy NGC 3783, obtained with the medium resolution echelle gratings of the Space Telescope Imaging Spectrograp…