Publications (85)
Occurrence and Global Properties of Narrow CIV lambda 1549 Absorption Lines in Moderate-Redshift Quasars
M. Vestergaard
A statistical study is presented of (a) the frequency of narrow CIV lambda 1549 absorption lines in 1.5 <~ z <~ 3.6 radio-quiet and radio-loud quasars, and of (b) the UV and radio…
Fuelling the central region of galaxies with misaligned gas accretion
J. L. Tous, S. I. Raimundo, R. Riffel +3
The paper investigates how gas that is kinematically misaligned with a galaxy’s disk fuels central star formation and potentially black‑hole growth, finding that this accretion sus…
Estimating Masses of Supermassive Black Holes in Active Galactic Nuclei from the Halpha Emission Line
E. Dalla BontÃ, B. M. Peterson, C. J. Grier +19
The goal of this project is to construct an estimator for the masses of supermassive black holes in active galactic nuclei (AGNs) based on the broad Halpha emission line. We make u…
Quasar Elemental Abundances at High Redshifts
M. Dietrich, F. Hamann, J. C. Shields +5
We examine rest-frame ultraviolet spectra of 70 high redshift quasars (z>3.5) to study the chemical enrichment history of the gas closely related to the quasars, and thereby estima…
Swift/UVOT grism monitoring of NGC 5548 in 2013: an attempt at MgII reverberation mapping
E. M. Cackett, K. Gultekin, M. C. Bentz +4
Reverberation-mapping-based scaling relations are often used to estimate the masses of black holes from single-epoch spectra of AGN. While the radius-luminosity relation that is th…
Narrow CIV lambda 1549A Absorption Lines in Moderate-Redshift Quasars
M. Vestergaard
A large, high-quality spectral data base of well-selected, moderate-redshift radio-loud and radio-quiet quasars is used to characterize the incidence of narrow associated CIV lambd…
Clues to Quasar Broad Line Region Geometry and Kinematics
M. Vestergaard, B. J. Wilkes, P. D. Barthel
We present evidence that the high-velocity CIV lambda 1549 emission line gas of radio-loud quasars may originate in a disk-like configuration, in close proximity to the accretion d…
Serendipitous discovery of a projected pair of QSOs separated by 4.5 arcsec on the sky
K. E. Heintz, J. P. U. Fynbo, J. -K. Krogager +8
We present the serendipitous discovery of a projected pair of quasi-stellar objects (QSOs) with an angular separation of arcsec. The redshifts of the two QSOs are widel…
MUSE observations of a changing-look AGN I: The re-appearance of the broad emission lines
S. I. Raimundo, M. Vestergaard, J. Y. Koay +3
Optical changing-look Active Galactic Nuclei (AGN) are a class of sources that change type within a short timescale of years or decades. This change is characterised by the appeara…
Evidence for Early or Efficient Black-Hole Growth
M. Vestergaard
Mass estimates, based on scaling relationships, are presented of central black holes in luminous quasars at a range of redshifts (z < 0.5, 1.2 ~< z ~< 6.3). The data show that very…
Variability of Fe II Emission Features in the Seyfert 1 Galaxy NGC 5548
M. Vestergaard, B. M. Peterson
We study the low-contrast Fe II emission blends in the ultraviolet (1250--2200A) and optical (4000--6000A) spectra of the Seyfert 1 galaxy NGC 5548 and show that these features var…
Monitoring of the Einstein Cross with the Nordic Optical Telscope
R. Oestensen, S. Refsdal, R. Stabell +26
We report results from five years of monitoring of the Einstein Cross (Q 2237+0305) with the Nordic Optical Telescope. The photometry, mainly in the R and I bands, has been perform…
Solving the conundrum of intervening strong MgII absorbers towards GRBs and quasars
L. Christensen, S. D. Vergani, S. Schulze +33
Previous studies have shown that the incidence rate of intervening strong MgII absorbers towards GRBs were a factor of 2 - 4 higher than towards quasars. Exploring the similar size…
ALMA Probes the Molecular Gas Reservoirs in the Changing-Look Seyfert Galaxy Mrk 590
J. Y. Koay, M. Vestergaard, V. Casasola +2
We investigate if the active galactic nucleus (AGN) of Mrk 590, whose supermassive black hole was until recently highly accreting, is turning off due to a lack of central gas to fu…
The Size of the Narrow-Line Emitting Region in the Seyfert 1 Galaxy NGC 5548 from Emission-Line Variability
B. M. Peterson, K. D. Denney, G. De Rosa +8
The narrow [O III] 4959, 5007 emission-line fluxes in the spectrum of the well-studied Seyfert 1 galaxy NGC 5548 are shown to vary with time. From this we show that the narrow line…
Space Telescope and Optical Reverberation Mapping Project. IX. Velocity-Delay Maps for Broad Emission Lines in NGC 5548
Keith Horne, G. De Rosa, B. M. Peterson +155
We report velocity-delay maps for prominent broad emission lines, Ly_alpha, CIV, HeII and H_beta, in the spectrum of NGC5548. The emission-line responses inhabit the interior of a…
An Empirical Ultraviolet Iron Spectrum Template Applicable to Active Galaxies
M. Vestergaard, B. J. Wilkes
Iron emission is often a severe contaminant in optical-ultraviolet spectra of active galaxies. Its presence complicates emission line studies. A viable solution, already successful…
[OII] Emission, Eigenvector 1 and Orientation in Radio-quiet Quasars
J. Kuraszkiewicz, B. J. Wilkes, W. N. Brandt +1
We present supportive evidence that the Boroson and Green eigenvector 1 is not driven by source orientation. Until recently it was generally accepted that eigenvector 1 does not de…
A nuclear molecular outflow in the Seyfert galaxy NGC3227
A. Alonso-Herrero, S. Garcia-Burillo, M. Pereira-Santaella +24
We present ALMA observations of the CO(2-1) and CO(3-2) molecular gas transitions and associated (sub)-mm continua of the nearby Seyfert 1.5 galaxy NGC3227 with angular resolutions…
Hubble Space Telescope Observations of Extended [O III] λ5007 Emission in Nearby QSO2s: New Constraints On AGN / Host Galaxy Interaction
Travis C. Fischer, S. B. Kraemer, H. R. Schmitt +15
We present a Hubble Space Telescope (HST) survey of extended [O III] λ5007 emission for a sample of 12 nearby (z < 0.12), luminous Type 2 quasars (QSO2s), which we use to measure…
Quasar Mass Functions Across Cosmic Time
M. Vestergaard
I present mass functions of actively accreting black holes detected in different quasar surveys which in concert cover a wide range of cosmic history. I briefly address what we lea…
Space Telescope and Optical Reverberation Mapping Project. VIII. Time Variability of Emission and Absorption in NGC 5548 Based on Modeling the Ultraviolet Spectrum
G. A. Kriss, G. De Rosa, J. Ely +164
We model the ultraviolet spectra of the Seyfert 1 galaxy NGC~5548 obtained with the Hubble Space Telescope during the 6-month reverberation-mapping campaign in 2014. Our model of t…
Modelling the AGN broad line region using single-epoch spectra I. The test case of Arp 151
S. I. Raimundo, A. Pancoast, M. Vestergaard +2
We show that individual (single-epoch) spectra of AGN can constrain some of the geometry and dynamics of the AGN broad line region. Studies of the cosmic influence of supermassive…
Central Masses and Broad-Line Region Sizes of Active Galactic Nuclei. II. A Homogeneous Analysis of a Large Reverberation-Mapping Database
B. M. Peterson, L. Ferrarese, K. M. Gilbert +9
We present improved black hole masses for 35 active galactic nuclei (AGNs) based on a complete and consistent reanalysis of broad emission-line reverberation-mapping data. From obj…
Mass Functions of the Active Black Holes in Distant Quasars from the Large Bright Quasar Survey, the Bright Quasar Survey, and the Color-Selected Sample of the SDSS Fall Equatorial Stripe
M. Vestergaard, Patrick S. Osmer
We present mass functions of distant actively accreting supermassive black holes residing in luminous quasars discovered in the Large Bright Quasar Survey, the Bright Quasar Survey…
The spectral state transition of Mkn 590, a potential link between AGNs and X-ray binaries?
B. Palit, A. Rozanska, A. G. Markowitz +8
Using the decade-long multi-band \textit{Swift} observations of the changing look AGN Markarian~590, we capture a clear state transition associated with its recent changing look ev…
Intensive broadband reverberation mapping of Fairall 9 with 1.8 years of daily Swift monitoring
R. Edelson, B. M. Peterson, J. Gelbord +5
We present 1.8 years of near-daily Swift monitoring of the bright, strongly variable Type 1 AGN Fairall 9. Totaling 575 successful visits, this is the largest such campaign reporte…
Determining Central Black Hole Masses in Distant Active Galaxies and Quasars. II. Improved Optical and UV Scaling Relationships
M. Vestergaard, B. M. Peterson
We present four improved empirical relationships useful for estimating the central black hole mass in nearby AGNs and distant luminous quasars alike using either optical or UV sing…
Hubble Space Telescope Observations of [O~III] Emission in Nearby QSO2s: Physical Properties of the Ionised Outflows
Anna Trindade Falcao, S. B. Kraemer, T. C. Fischer +14
We use Hubble Space Telescope (HST)/ Space Telescope Imaging Spectrograph (STIS) long-slit G430M and G750M spectra to analyse the extended [O~III] 5007A emission in a sample of twe…
Space Telescope and Optical Reverberation Mapping Project. XI. Disk-wind characteristics and contributions to the very broad emission lines of NGC 5548
M. Dehghanian, G. J. Ferland, G. A. Kriss +22
In 2014 the NGC 5548 Space Telescope and Optical Reverberation Mapping campaign discovered a two-month anomaly when variations in the absorption and emission lines decorrelated fro…
Early Growth and Efficient Accretion of Massive Black Holes at High Redshift
M. Vestergaard
Black-hole masses of the highest redshift quasars (4 <~ z <~ 6) are estimated using a previously presented scaling relationship, derived from reverberation mapping of nearby quasar…
The First Swift Intensive AGN Accretion Disk Reverberation Mapping Survey
R. Edelson, J. Gelbord, E. Cackett +32
Swift intensive accretion disk reverberation mapping of four AGN yielded light curves sampled 200-350 times in 0.3-10 keV X-ray and six UV/optical bands. Uniform reduction an…
Parsec-scale radio morphology and variability of a changing-look AGN: the case of Mrk 590
J. Y. Koay, M. Vestergaard, H. E. Bignall +2
We investigate the origin of the parsec-scale radio emission from the changing-look active galactic nucleus (AGN) of Mrk 590, and examine whether the radio power has faded concurre…
Velocity-resolved reverberation mapping of five bright Seyfert 1 galaxies
G. De Rosa, M. M. Fausnaugh, C. J. Grier +99
We present the first results from a reverberation-mapping campaign undertaken during the first half of 2012, with additional data on one AGN (NGC 3227) from a 2014 campaign. Our ma…
Space Telescope and Optical Reverberation Mapping Project. II. Swift and HST Reverberation Mapping of the Accretion Disk of NGC 5548
R. Edelson, J. M. Gelbord, K. Horne +47
Recent intensive Swift monitoring of the Seyfert 1 galaxy NGC 5548 yielded 282 usable epochs over 125 days across six UV/optical bands and the X-rays. This is the densest extended…
VLT identification of the optical afterglow of the gamma-ray burst GRB 000131 at z=4.50
M. I. Andersen, J. Hjorth, H. Pedersen +16
We report the discovery of the gamma-ray burst GRB 000131 and its optical afterglow. The optical identification was made with the VLT 84 hours after the burst following a BATSE det…
Swift monitoring of NGC 4151: Evidence for a Second X-ray/UV Reprocessing
R. Edelson, J. Gelbord, E. Cackett +41
Swift monitoring of NGC 4151 with ~6 hr sampling over a total of 69 days in early 2016 is used to construct light curves covering five bands in the X-rays (0.3-50 keV) and six in t…
EELT-HIRES the high-resolution spectrograph for the E-ELT
A. Marconi, P. Di Marcantonio, V. D'Odorico +70
The first generation of E-ELT instruments will include an optical-infrared High Resolution Spectrograph, conventionally indicated as EELT-HIRES, which will be capable of providing…
X-Ray and Optical Variability in NGC 4051 and the Nature of Narrow-Line Seyfert 1 Galaxies
B. M. Peterson, I. M. McHardy, B. J. Wilkes +14
We report on the results of a three-year program of coordinated X-ray and optical monitoring of the narrow-line Seyfert 1 galaxy NGC 4051. The rapid continuum variations observed i…
Hubble Space Telescope [O III] Emission-Line Kinematics in Two Nearby QSO2s: A Case for X-ray Feedback
Anna Trindade Falcão, S. B. Kraemer, T. C. Fischer +15
We present a dynamical study of the narrow-line regions in two nearby QSO2s. We construct dynamical models based on detailed photoionization models of the emission-line gas, includ…
A Revised Broad-Line Region Radius and Black Hole Mass for the Narrow-Line Seyfert 1 NGC 4051
K. D. Denney, L. C. Watson, B. M. Peterson +30
We present the first results from a high sampling rate, multi-month reverberation mapping campaign undertaken primarily at MDM Observatory with supporting observations from telesco…
Discovery of a faint optical jet in 3C 120
J. Hjorth, M. Vestergaard, A. N. Sorensen +1
We report the detection of an optical jet in the nearby Seyfert 1 radio galaxy 3C 120. The optical jet coincides with the well-known radio jet and emits continuum radiation (B,V',I…
Emission Line Properties of AGN from a post-COSTAR FOS HST Spectral Atlas
J. K. Kuraszkiewicz, P. J. Green, D. M. Crenshaw +4
This paper joins a series compiling consistent emission line measurements of large AGN spectral databases, useful for reliable statistical studies of emission line properties. It i…
High Redshift Standard Candles: Predicted Cosmological Constraints
A. L. King, T. M. Davis, K. Denney +2
We investigate whether future measurements of high redshift standard candles (HzSCs) will be a powerful probe of dark energy, when compared to other types of planned dark energy me…
Space Telescope and Optical Reverberation Mapping Project. I. Ultraviolet Observations of the Seyfert 1 Galaxy NGC 5548 with the Cosmic Origins Spectrograph on Hubble Space Telescope
G. De Rosa, B. M. Peterson, J. Ely +47
We describe the first results from a six-month long reverberation-mapping experiment in the ultraviolet based on 170 observations of the Seyfert 1 galaxy NGC 5548 with the Cosmic O…
High Redshift Quasars and Star Formation in the Early Universe
M. Dietrich, I. Appenzeller, M. Vestergaard +1
In order to derive information on the star formation history in the early universe we observed 6 high-redshift (z=3.4) quasars in the near-infrared to measure the relative iron and…
A new cosmological distance measure using AGN
D. Watson, K. D. Denney, M. Vestergaard +1
Accurate distances to celestial objects are key to establishing the age and energy density of the Universe and the nature of dark energy. A distance measure using active galactic n…
Continuum and Emission Line Strength Relations for a large Active Galactic Nuclei Sample
M. Dietrich, F. Hamann, J. C. Shields +5
We report on the analysis of a large sample of 744 type 1 Active Galactic Nuclei, including quasars and Seyfert 1 galaxies across the redshift range from 0 < z < 5 and spanning nea…
XQ-100: A legacy survey of one hundred 3.5 < z < 4.5 quasars observed with VLT/XSHOOTER
S. Lopez, V. D'Odorico, S. L. Ellison +23
We describe the execution and data reduction of the European Southern Observatory Large Programme "Quasars and their absorption lines: a legacy survey of the high-redshift universe…
Hot, Photoionized X-ray Gas in Two Luminous Type 2 Quasars: Chandra-HST Evidence for a Wind-Driven Sequence
Anna Trindade Falcão, S. Kraemer, L. Feuillet +17
We present new Chandra/ACIS-S imaging spectroscopy of two luminous type 2 quasars, FIRST J120041.4+314745 (=0.116) and 2MASX J13003807+5454367 (=0.088), and compare their X-r…
Space Telescope and Optical Reverberation Mapping Project. III. Optical Continuum Emission and Broad-Band Time Delays in NGC 5548
M. M. Fausnaugh, K. D. Denney, A. J. Barth +94
We present ground-based optical photometric monitoring data for NGC 5548, part of an extended multi-wavelength reverberation mapping campaign. The light curves have nearly daily ca…
Reverberation Mapping Results from MDM Observatory
Kelly D. Denney, B. M. Peterson, R. W. Pogge +6
We present results from a multi-month reverberation mapping campaign undertaken primarily at MDM Observatory with supporting observations from around the world. We measure broad li…
Diverse Broad Line Region Kinematic Signatures From Reverberation Mapping
K. D. Denney, B. M. Peterson, R. W. Pogge +40
A detailed analysis of the data from a high sampling rate, multi-month reverberation mapping campaign, undertaken primarily at MDM Observatory with supporting observations from tel…
The UV spectra of NLS1s - Implications for their broad line regions
J. K. Kuraszkiewicz, B. J. Wilkes, B. Czerny +3
We study the UV spectra of NLS1 galaxies and compare them with typical Seyfert 1 galaxies and quasars. The NLS1 spectra show narrower UV lines as well as weaker CIV lambda 1549 and…
Elemental Abundances in the Broad Emission Line Region of Quasars at Redshifts larger than 4
M. Dietrich, I. Appenzeller, F. Hamann +4
We present observations of 11 high redshift quasars ($3.9 \la z \la 5.0$) observed with low spectral resolution in the restframe ultraviolet using FORS 1 at the VLT UT 1. The emiss…
The Changing-Look Quasar Mrk 590 is Awakening
S. Mathur, K. D. Denney, A. Gupta +9
Mrk 590 was originally classified as a Seyfert 1 galaxy, but then it underwent dramatic changes: the nuclear luminosity dropped by over two orders of magnitude and the broad emissi…
Black Hole Masses of High-Redshift Quasars
M. Vestergaard
Black-hole masses of distant quasars cannot be measured directly, but can be estimated to within a factor 3 to 5 using scaling relationships involving the quasar luminosity and bro…
The High A(V) Quasar Survey: Reddened quasi-stellar objects selected from optical/near-infrared photometry - II
J. -K. Krogager, S. Geier, J. P. U. Fynbo +9
Quasi-stellar objects (QSOs) whose spectral energy distributions (SEDs) are reddened by dust either in their host galaxies or in intervening absorber galaxies are to a large degree…
Space Telescope and Optical Reverberation Mapping Project. XII. Broad-Line Region Modeling of NGC 5548
P. R. Williams, A. Pancoast, T. Treu +155
We present geometric and dynamical modeling of the broad line region for the multi-wavelength reverberation mapping campaign focused on NGC 5548 in 2014. The dataset includes photo…
The extended High A(V) Quasar Survey: Searching for dusty absorbers toward mid-infrared selected quasars
J. -K. Krogager, J. P. U. Fynbo, K. E. Heintz +6
We present the results of a new spectroscopic survey for dusty intervening absorption systems, particularly damped Ly absorbers (DLAs), towards reddened quasars. The candidate…
Space Telescope and Optical Reverberation Mapping Project. VII. Understanding the UV anomaly in NGC 5548 with X-Ray Spectroscopy
S. Mathur, A. Gupta, K. Page +147
During the Space Telescope and Optical Reverberation Mapping Project (STORM) observations of NGC 5548, the continuum and emission-line variability became de-correlated during the s…
Black-Hole Mass Measurements
M. Vestergaard
The applicability and apparent uncertainties of the techniques currently available for measuring or estimating black-hole masses in AGNs are briefly summarized.
Echo mapping of the black hole accretion flow in NGC 7469
Raj Prince, Juan V. Hernández Santisteban, Keith Horne +20
Reverberation mapping (RM) can measure black hole accretion disc sizes and radial structure through observed time lags that should increase with wavelength as .…
Hubble Space Telescope Observations of Nearby Type 1 Quasars. I. Characterisation of the Extended [O III] 5007Ã Emission
Anna Trindade Falcão, S. B. Kraemer, T. C. Fischer +13
We use the Hubble Space Telescope to analyse the extended [O III] 5007A emission in seven bright radio-quiet type 1 quasars (QSO1s), focusing on the morphology and physical conditi…
Multiwavelength Monitoring of the Narrow-Line Seyfert 1 Galaxy Akn 564. III. Optical Observations and the Optical--UV--X-ray Connection
O. Shemmer, P. Romano, R. Bertram +36
We present the results of a two-year long optical monitoring program of the narrow-line Seyfert 1 galaxy Akn 564. The majority of this monitoring project was also covered by X-ray…
X-ray Emission from the Radio Jet in 3C 120
D. E. Harris, J. Hjorth, A. C. Sadun +2
We report the discovery of X-ray emission from a radio knot at a projected distance of 25" from the nucleus of the Seyfert galaxy, 3C 120. The data were obtained with the ROSAT Hig…
Space Telescope and Optical Reverberation Mapping Project. X. Understanding the Absorption-Line Holiday in NGC 5548
M. Dehghanian, G. J. Ferland, G. A. Kriss +27
The flux variations in the emission lines in active galactic nuclei (AGNs) are driven by variations in the ionizing continuum flux --which are usually reflected in the observable U…
Space Telescope and Optical Reverberation Mapping Project VI: reverberating Disk Models for NGC 5548
D. Starkey, Keith Horne, M. M. Fausnaugh +90
We conduct a multiwavelength continuum variability study of the Seyfert 1 galaxy NGC 5548 to investigate the temperature structure of its accretion disk. The 19 overlapping continu…
Intensive disc-reverberation mapping of Fairall 9: 1st year of Swift & LCO monitoring
J. V. Hernández Santisteban, R. Edelson, K. Horne +33
We present results of time-series analysis of the first year of the Fairall 9 intensive disc-reverberation campaign. We used Swift and the Las Cumbres Observatory global telescope…
Determining Central Black Hole Masses in Distant Active Galaxies
M. Vestergaard
An empirical relationship, of particular interest for studies of high redshift active galactic nuclei (AGNs) and quasars, between the masses of their central black-holes and rest-f…
A dusty compact object bridging galaxies and quasars at cosmic dawn
S. Fujimoto, G. B. Brammer, D. Watson +18
Understanding how super-massive black holes form and grow in the early Universe has become a major challenge since the discovery of luminous quasars only 700 million years after th…
Space Telescope and Optical Reverberation Mapping Project. V. Optical Spectroscopic Campaign and Emission-Line Analysis for NGC 5548
L. Pei, M. M. Fausnaugh, A. J. Barth +153
We present the results of an optical spectroscopic monitoring program targeting NGC 5548 as part of a larger multi-wavelength reverberation mapping campaign. The campaign spanned s…
Determining the fraction of reddened quasars in COSMOS with multiple selection techniques from X-ray to radio wavelengths
K. E. Heintz, J. P. U. Fynbo, P. Møller +8
The sub-population of quasars reddened by intrinsic or intervening clouds of dust are known to be underrepresented in optical quasar surveys. By defining a complete parent sample o…
A Sample of Quasars with Strong Nitrogen Emission Lines from the Sloan Digital Sky Survey
Linhua Jiang, Xiaohui Fan, M. Vestergaard
We report on 293 quasars with strong NIV] lambda 1486 or NIII] lambda 1750 emission lines (rest-frame equivalent width > 3 Ã ) at 1.7 < z < 4.0 selected from the Sloan Digital Sky…
An Empirical Ultraviolet Template for Iron Emission in Quasars as Derived from I Zw 1
M. Vestergaard, B. J. Wilkes
We present an empirical template spectrum suitable for fitting/subtracting and studying the FeII and FeIII line emission in the restframe UV spectra of active galatic nuclei (AGNs)…
Black-hole masses of distant quasars
M. Vestergaard
A brief overview of the methods commonly used to determine or estimate the black hole mass in quiescent or active galaxies is presented and it is argued that the use of mass-scalin…
On the Scatter in the Radius - Luminosity Relationship for Active Galactic Nuclei
E. Kilerci Eser, M. Vestergaard, B. M. Peterson +2
We investigate and quantify the observed scatter in the empirical relationship between the broad line region size R and the luminosity of the active galactic nucleus (AGN), in orde…
Optical/near-infrared selection of red QSOs: Evidence for steep extinction curves towards galactic centers?
J. P. U. Fynbo, J. -K. Krogager, B. Venemans +5
We present the results of a search for red QSOs using a selection based on optical imaging from SDSS and near-infrared imaging from UKIDSS. For a sample of 58 candidates 46 (79%) a…
Mass Functions of the Active Black Holes in Distant Quasars from the Sloan Digital Sky Survey Data Release 3
M. Vestergaard, X. Fan, C. A. Tremonti +2
We present the mass functions of actively accreting supermassive black holes over the redshift range 0.3 <= z <= 5 for a well-defined, homogeneous sample of 15,180 quasars from the…
Space Telescope and Optical Reverberation Mapping Project. IV. Anomalous behavior of the broad ultraviolet emission lines in NGC 5548
M. R. Goad, K. T. Korista, G. De Rosa +99
During an intensive Hubble Space Telescope (HST) Cosmic Origins Spectrograph (COS) UV monitoring campaign of the Seyfert~1 galaxy NGC 5548 performed from 2014 February to July, the…
FeII/MgII Emission Line Ratio in High Redshift Quasars
M. Dietrich, F. Hamann, I. Appenzeller +1
We present results of the analysis of near infrared spectroscopic observations of 6 high-redshift quasars (z > 4), emphasizing the measurement of the ultraviolet FeII/MgII emission…
Modelling the AGN broad line region using single-epoch spectra II. Nearby AGN
S. I. Raimundo, M. Vestergaard, M. R. Goad +4
The structure of the broad line region (BLR) is an essential ingredient in the determination of active galactic nuclei (AGN) virial black hole masses, which in turn are important t…
Reverberation Mapping Measurements of Black Hole Masses in Six Local Seyfert Galaxies
K. D. Denney, B. M. Peterson, R. W. Pogge +40
We present the final results from a high sampling rate, multi-month, spectrophotometric reverberation mapping campaign undertaken to obtain either new or improved Hbeta reverberati…
The Galaxy Counterparts of the two high-metallicity DLAs at z=2.412 and z=2.583 towards Q0918+1636
J. P. U. Fynbo, S. Geier, L. Christensen +9
The quasar Q0918+1636 (z=3.07) has two intervening high-metallicity Damped Lyman-alpha Absorbers (DLAs) along the line of sight, at redshifts of z=2.412 and 2.583. The z=2.583 DLA…
Spectroscopy of the short-hard GRB 130603B: The host galaxy and environment of a compact object merger
A. de Ugarte Postigo, C. C. Thoene, A. Rowlinson +40
Short duration gamma-ray bursts (SGRBs) are thought to be related to the violent merger of compact objects, such as neutron stars or black holes, which makes them promising sources…