Bentz, Misty C., Peterson, Bradley M., Netzer, Hagai, Pogge, Richard W., Vestergaard, Marianne
We present high-resolution HST images of all 35 AGNs with optical reverberation-mapping results, which we have modeled to create a nucleus-free image of each AGN host galaxy. From the nucleus-free...
Bentz, Misty C., Peterson, Bradley M., Pogge, Richard W., Vestergaard, Marianne
We investigate the relationship between black hole mass and bulge luminosity for AGNs with reverberation-based black hole mass measurements and bulge luminosities from two-dimensional decompositions...
Systematic Uncertainties in Black Hole Masses Determined from Single Epoch Spectra (2008)
Denney, Kelly D., Peterson, Bradley M., Dietrich, Matthias, Vestergaard, Marianne, Bentz, Misty C.
We explore the nature of systematic errors that can arise in measurement of black hole masses from single-epoch spectra of active galactic nuclei (AGNs) by utilizing the many epochs available for NGC...
Watson, Linda C., Martini, Paul, Dasyra, Kalliopi M., Bentz, Misty C., Ferrarese, Laura, Peterson, Bradley M., ...
We present the first use of the Gemini North laser guide star adaptive optics (LGS AO) system and an integral field unit (IFU) to measure the stellar velocity dispersion of the host of a luminous...
Watson, Linda C., Martini, Paul, Dasyra, Kalliopi M., Bentz, Misty C., Ferrarese, Laura, Peterson, Bradley M., ...
We present the first use of the Gemini North laser guide star adaptive optics (LGS AO) system and an integral field unit (IFU) to measure the stellar velocity dispersion of the host of a luminous...
The Observatory for Multi-Epoch Gravitational Lens Astrophysics (OMEGA) (2008)
Moustakas, Leonidas A, Bolton, Adam J, Booth, Jeffrey T, Bullock, James S, Cheng, Edward, Coe, Dan, ...
(abridged) The Observatory for Multi-Epoch Gravitational Lens Astrophysics (OMEGA) is a mission concept for a 1.5-m near-UV through near-IR space observatory that will be dedicated to frequent...
Watson, Linda C., Martini, Paul, Dasyra, Kalliopi M., Bentz, Misty C., Ferrarese, Laura, Peterson, Bradley M., ...
The Observatory for Multi-Epoch Gravitational Lens Astrophysics (OMEGA) (2008)
Moustakas, Leonidas A., Bolton, Adam J., Booth, Jeffrey T., Bullock, James S., Cheng, Edward, Coe, Dan, ...
Stefan Collier, Keith Horne, Bradley M. Peterson
We show how wavelength-dependent time delays between continuum flux variations of AGN can be used to test the standard black hole-accretion disc paradigm, by measuring the temperature structure T (R)...
Reverberation Mapping And The Physics Of Active Galactic Nuclei (2007)
Hagai Netzer, Bradley M. Peterson
. Reverberation-mapping campaigns have revolutionized our understanding of AGN. They have allowed the direct determination of the broad-line region size, enabled mapping of the gas distribution...
Monitoring Of Active Galactic Nuclei: The Why And The How (2007)
Danielle Alloin, O Giovanna Stirpe, Bradley M. Peterson
this report. Similar programmes, albeit with a sometimes different overall emphasis, have been undertaken by other informal organizations during the same time frame. For example, the European...
On the size of the Fe II emitting region in the AGN Akn 120 (2007)
Kuehn, Charles A., Baldwin, Jack A., Peterson, Bradley M., Korista, Kirk T.
We present a reverberation analysis of the strong, variable optical Fe II emission bands in the spectrum of Akn 120, a low-redshift AGN which is one of the best candidates for such a study. On time...
Onken, Christopher A., Valluri, Monica, Peterson, Bradley M., Pogge, Richard W., Bentz, Misty C., Ferrarese, Laura, ...
We present a stellar dynamical estimate of the black hole (BH) mass in the Seyfert 1 galaxy, NGC 4151. We analyze ground-based spectroscopy as well as imaging data from the ground and space, and we...
The Near-Infrared Broad Emission Line Region of Active Galactic Nuclei -- I. The Observations (2007)
Landt, Hermine, Bentz, Misty C., Ward, Martin J., Elvis, Martin, Peterson, Bradley M., Korista, Kirk T., ...
We present high quality (high signal-to-noise ratio and moderate spectral resolution) near-infrared (near-IR) spectroscopic observations of 23 well-known broad-emission line active galactic nuclei...
The Masses of Black Holes in Active Galactic Nuclei (2007)
Reverberation mapping methods have been used to measure masses in about three dozen AGNs. The consistency of the virial masses computed from line widths and time delays, the relationship between...
NGC 5548 in a Low-Luminosity State: Implications for the Broad-Line Region (2007)
Bentz, Misty C., Denney, Kelly D., Cackett, Edward M., Dietrich, Matthias, Fogel, Jeffrey K. J., Ghosh, Himel, ...
We describe results from a new ground-based monitoring campaign on NGC 5548, the best studied reverberation-mapped AGN. We find that it was in the lowest luminosity state yet recorded during a...
Refining the Radius-Luminosity Relationship for Active Galactic Nuclei (2007)
Bentz, Misty C., Denney, Kelly D., Peterson, Bradley M., Pogge, Richard W.
We have measured the host-galaxy starlight contribution to four lower-luminosity AGNs (NGC 3516, NGC 4593, IC 4329A, and NGC 7469). We include these objects with new broad line region measurements...
The Mass of the Black Hole in the Seyfert 1 Galaxy NGC 4593 from Reverberation Mapping (2006)
Denney, Kelly D., Bentz, Misty C., Peterson, Bradley M., Pogge, Richard W., Cackett, Edward M., Dietrich, Matthias, ...
We present new observations leading to an improved black hole mass estimate for the Seyfert 1 galaxy NGC 4593 as part of a reverberation-mapping campaign conducted at the MDM Observatory....
A Reverberation-Based Mass for the Central Black Hole in NGC 4151 (2006)
Bentz, Misty C., Denney, Kelly D., Cackett, Edward M., Dietrich, Matthias, Fogel, Jeffrey K. J., Ghosh, Himel, ...
We have undertaken a new ground-based monitoring campaign to improve the estimates of the mass of the central black hole in NGC 4151. We measure the lag time of the broad H beta line response...
Desroches, Louis-Benoit, Filippenko, Alexei V., Kaspi, Shai, Laor, Ari, Maoz, Dan, Ganeshalingam, Mohan, ...
We present optical observations of the low-luminosity Seyfert 1 nucleus of NGC 4395, as part of a multiwavelength reverberation-mapping program. Observations were carried out over two nights in 2004...
Frank, Stephan, Bentz, Misty C., Stanek, Krzysztof Z., Mathur, Smita, Dietrich, Matthias, Peterson, Bradley M., ...
We examine the recent report by Prochter et al. (2006) that gamma-ray burst (GRB) sight lines have a much higher incidence of strong MgII absorption than quasar sight lines. We propose that the...
The Mass of the Central Black Hole in the Seyfert Galaxy NGC 4151 (2006)
Metzroth, Kyle G., Onken, Christopher A., Peterson, Bradley M.
In order to improve the reverberation-mapping based estimate of the mass of the central supermassive black hole in the Seyfert 1 galaxy NGC 4151, we have reanalyzed archival ultraviolet monitoring...
O'Neill, Paul M., Kaspi, Shai, Laor, Ari, Nandra, Kirpal, Moran, Edward C., Peterson, Bradley M., ...
We report on two Chandra observations, and a simultaneous Hubble Space Telescope ultraviolet observation, of the dwarf Seyfert 1 galaxy NGC 4395. Each Chandra observation had a duration of ~30 ks,...
Bentz, Misty C., Peterson, Bradley M., Pogge, Richard W., Vestergaard, Marianne, Onken, Christopher A.
We have obtained high resolution images of the central regions of 14 reverberation-mapped active galactic nuclei (AGN) using the Hubble Space Telescope Advanced Camera for Surveys High Resolution...
Peterson, Bradley M., Bentz, Misty C., Desroches, Louis-Benoit, Filippenko, Alexei V., Ho, Luis C., Kaspi, Shai, ...
A reverberation-mapping program on NGC 4395, the least-luminous known Seyfert 1 galaxy, undertaken with the Space Telescope Imaging Spectrograph on the Hubble Space Telescope, yields a measurement of...
The Relationship Between Luminosity and Broad-Line Region Size in Active Galactic Nuclei (2005)
Kaspi, Shai, Maoz, Dan, Netzer, Hagai, Peterson, Bradley M., Vestergaard, Marianne, Jannuzi, Buell T.
We reinvestigate the relationship between the characteristic broad-line region size (R_blr) and the Balmer emission-line, X-ray, UV, and optical continuum luminosities. Our study makes use of the...
Onken, Christopher A., Ferrarese, Laura, Merritt, David, Peterson, Bradley M., Pogge, Richard W., Vestergaard, Marianne, ...
We calibrate reverberation-based black hole masses in active galactic nuclei (AGNs) by using the correlation between black hole mass, M, and bulge/spheroid stellar velocity dispersion, sigma. We use...
Black Hole Masses from Reverberation Measurements (2004)
We have reanalyzed in a consistent way existing reverberation data for 35 AGNs for the purpose of refining the black hole masses derived from these data. We find that the precision (or random...
Correlated long-term optical and x-ray variations in NGC 5548 (2003)
Uttley, Phillip, Edelson, Rick, McHardy, Ian, Peterson, Bradley M., Markowitz, Alex
We combine the long-term optical light curve of the Seyfert 1 galaxy NGC5548 with the X-ray light curve measured by the Rossi X-ray Timing Explorer over 6 years, to determine the relationship between...
Correlated long-term optical and X-ray variations in NGC 5548 (2003)
Uttley, Phil, Edelson, Rick, McHardy, Ian, Peterson, Bradley M., Markowitz, Alex
We combine the long-term optical light curve of the Seyfert 1 galaxy NGC5548 with the X-ray light curve measured by the Rossi X-ray Timing Explorer over 6 years, to determine the relationship between...
Correlated long-term optical and x-ray variations in NGC 5548 (2003)
Uttley, Philip, Edelson, Rick, McHardy, Ian M., Peterson, Bradley M., Markowitz, Alex
We combine the long-term optical light curve of the Seyfert 1 galaxy NGC 5548 with the X-ray light curve measured by the Rossi X-Ray Timing Explorer over 6 years, to determine the relationship...
An Intrinsic Baldwin Effect in the H-beta Broad Emission Line in the Spectrum of NGC 5548 (2002)
Gilbert, Karoline M., Peterson, Bradley M.
We investigate the possibility of an intrinsic Baldwin Effect (i.e.,nonlinear emission-line response to continuum variations) in the broad H-beta emission line of the active galaxy NGC 5548 using...
Masses of Black Holes in Active Galactic Nuclei (2002)
We present a progress report on a project whose goal is to improve both the precision and accuracy of everberation-based black-hole masses. Reverberation masses appear to be accurate to a factor of...
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...
The Structure and Energetics of Active Galactic Nuclei (2002)
The black-hole/accretion-disk paradigm for active galactic nuclei (AGNs) is now reasonably secure, but there are still important unresolved issues, some of which will require the capabilities of an 8...
The Mass of the Central Black Hole in the Seyfert Galaxy NGC 3783 (2002)
Onken, Christopher A., Peterson, Bradley M.
Improved analysis of ultraviolet and optical monitoring data on the Seyfert 1 galaxy NGC 3783 provides evidence for the existence of a supermassive, (8.7+/-1.1)x10^6 M_sun, black hole in this galaxy....
Observational Requirements for High-Fidelity Reverberation Mapping (2002)
Horne, Keith, Peterson, Bradley M., Collier, Stefan J., Netzer, Hagai
We present a series of simulations to demonstrate that high-fidelity velocity-delay maps of the emission-line regions in active galactic nuclei can be obtained from time-resolved spectrophotometric...
Variability of Active Galactic Nuclei (2001)
Continuum and emission-line variability of active galactic nuclei provides a powerful probe of microarcsecond scale structures in the central regions of these sources. In this contribution, we review...
Ferrarese, Laura, Pogge, Richard W., Peterson, Bradley M., Merritt, David, Wandel, Amri, Joseph, Charles L.
We report the first results of a program to measure accurate stellar velocity dispersions in the bulges of the host galaxies of active galactic nuclei (AGNs) for which accurate black hole (BH) masses...
Peterson, Bradley M., Wandel, Amri
Emission-line variability data for Seyfert 1 galaxies provide strong evidence for the existence of supermassive black holes in the nuclei of these galaxies, and that the line-emitting gas is moving...
Gross, Matthew F, Spear, Robert M, Peterson, Bradley M
Statement of findings Varying concentrations of helium-oxygen (heliox) mixtures were evaluated in mechanically ventilated children with bronchiolitis. We hypothesized that, with an increase in the...
Intensive HST, RXTE and ASCA Monitoring of NGC 3516: Evidence Against Thermal Reprocessing (1999)
Edelson, Rick, Koratkar, Anuradha, Nandra, Kirpal, Goad, Michael, Peterson, Bradley M., Collier, Stefan, ...
During 1998 April 13-16, NGC 3516 was monitored almost continuously with HST for 10.3 hr in the UV and 2.8 d in the optical, and simultaneous RXTE and ASCA monitoring covered the same period. The...
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...
Peterson, Bradley M., Wandel, Amri
Emission-line variability data on NGC 5548 argue strongly for the existence of a mass of order 7 x 10^7 solar masses within the inner few light days of the nucleus in the Seyfert 1 galaxy NGC 5548....
Collier, Stefan, Horne, Kieth, Wanders, Ignaz, Peterson, Bradley M.
We show how wavelength-dependent time delays between continuum flux variations of AGN can be used to test the standard black hole-accretion disc paradigm, by measuring the temperature structure...
Peterson, Bradley M., Wanders, Ignaz, Horne, Keith, Collier, Stefan, Alexander, Tal, Kaspi, Shai, ...
We describe a model-independent method of assessing the uncertainties in cross-correlation lags determined from AGN light curves, and use this method to investigate the reality of lags between UV and...
Optical Continuum and Emission-Line Variability of Seyfert 1 Galaxies (1998)
Peterson, Bradley M., Wanders, Ignaz, Bertram, Ray, Hunley, James F., Pogge, Richard W., Wagner, R. Mark
We present the light curves obtained during an eight-year program of optical spectroscopic monitoring of nine Seyfert 1 galaxies: 3C 120, Akn 120, Mrk 79, Mrk 110, Mrk 335, Mrk 509, Mrk 590, Mrk 704,...
Evidence for a Physically Compact Narrow-Line Region in the Seyfert 1 Galaxy NGC 5548 (1997)
Kraemer, Steven B., Crenshaw, D. Michael, Filippenko, Alexei V., Peterson, Bradley M.
We have combined HST/FOS and ground-based spectra of the Seyfert 1 galaxy NGC 5548 to study the narrow emission lines over the 1200 -- 10,000 angstrom region. All of the spectra were obtained when...
Reverberation Mapping and the Physics of Active Galactic Nuclei (1997)
Netzer, Hagai, Peterson, Bradley M.
Reverberation-mapping campaigns have revolutionized our understanding of AGN. They have allowed the direct determination of the broad-line region size, enabled mapping of the gas distribution around...
X-ray Observations of the Broad-Line Radio Galaxy 3C 390.3 (1997)
Leighly, Karen M., O'Brien, Paul T., Edelson, Rick, George, Ian M., Malkan, Matthew A., Matsuoka, Masaru, ...
We present the data and preliminary analysis for a series of 90 ROSAT HRI and two ASCA observations of the broad-line radio galaxy 3C 390.3. These data were obtained during the period 1995 January 2...
Gross, Matthew F, Spear, Robert M, Peterson, Bradley M
Varying concentrations of helium-oxygen (heliox) mixtures were evaluated in mechanically ventilated children with bronchiolitis. We hypothesized that, with an increase in the helium:oxygen ratio, and...
Gross, Matthew F, Spear, Robert M, Peterson, Bradley M
Varying concentrations of helium-oxygen (heliox) mixtures were evaluated in mechanically ventilated children with bronchiolitis. We hypothesized that, with an increase in the helium:oxygen ratio, and...