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Full-Text Articles in Physical Sciences and Mathematics
Exploring The Mass To Light Ratio Of Massive Galaxies With The Rubin Dp0 Preview Dataset, Denvir Joy Higgins
Exploring The Mass To Light Ratio Of Massive Galaxies With The Rubin Dp0 Preview Dataset, Denvir Joy Higgins
Physics
The Vera C. Rubin Observatory will perform the 10-year long Legacy Survey of Space and Time expected to begin in 2024. LSST will cover the Southern Hemisphere, collecting over two million images with an 8.4-meter telescope and 3200-pixel camera. In collaboration with the scientific community and based on the Outer Rim Simulation \citep{heit19}, the Rubin Observatory released a simulated dataset (DP0) of the data that is expected to be in hand at the 5-year mark. Using this simulated dataset, I have explored the number and luminosity of the most massive local galaxies. Using a sample of the brightest, closest galaxies …
Formation Pathways In Brightest Cluster Galaxies: Measuring The Distribution Of Ages, Metallicities, And Hydrodynamics Of Stellar Populations, Priscilla E. Holguin West
Formation Pathways In Brightest Cluster Galaxies: Measuring The Distribution Of Ages, Metallicities, And Hydrodynamics Of Stellar Populations, Priscilla E. Holguin West
Physics
Brightest Cluster Galaxies (BCGs) are the most massive galaxies in the local universe and have had the full age of the universe to build. This makes their formation and evolution history particularly interesting as they offer a glimpse at potential evolutionary pathways for younger systems. We present the radial profile of ages, metallicities, and preliminary classification of companions to 23 BCGs observed using the SparsePak instrument on WIYN by running the STARLIGHT stellar population synthesis models. This analysis of the BCGs’ stellar populations is done by separating each BCG into different regions, and preliminary results of the stellar populations for …
The Seoul National University Agn Monitoring Project. Ii. Blr Size And Black Hole Mass Of Two Agns, Suvendu Rakshit, Jong-Hak Woo, Elena Gallo, Edmund Hodges-Kluck, Jaejin Shin, Yiseul Jeon, Hyun-Jin Bae, Vivienne Baldassare, Hojin Cho, Wanjin Cho, Adi Foord, Daeun Kang, Wonseok Kang, Marios Karouzos, Minjin Kim, Taewoo Kim, Huynh Anh N. Lee, Daeseong Park, Hyun-Il Sung, Vardha N. Bennert, Matthew A. Malkan
The Seoul National University Agn Monitoring Project. Ii. Blr Size And Black Hole Mass Of Two Agns, Suvendu Rakshit, Jong-Hak Woo, Elena Gallo, Edmund Hodges-Kluck, Jaejin Shin, Yiseul Jeon, Hyun-Jin Bae, Vivienne Baldassare, Hojin Cho, Wanjin Cho, Adi Foord, Daeun Kang, Wonseok Kang, Marios Karouzos, Minjin Kim, Taewoo Kim, Huynh Anh N. Lee, Daeseong Park, Hyun-Il Sung, Vardha N. Bennert, Matthew A. Malkan
Physics
Active galactic nuclei (AGNs) show a correlation between the size of the broad line region and the monochromatic continuum luminosity at 5100 Å, allowing black hole mass estimation based on single-epoch spectra. However, the validity of the correlation is yet to be clearly tested for high-luminosity AGNs. We present the first reverberation mapping results of the Seoul National University AGN Monitoring Project (SAMP), which is designed to focus on luminous AGNs for probing the high end of the size–luminosity relation. We report time lag measurements of two AGNs, namely, 2MASS J10261389+5237510 and SDSS J161911.24+501109.2, using the light curves obtained over …
Hubble's Law Implies Benford's Law For Distances To Galaxies, Theodore P. Hill, Ronald F. Fox
Hubble's Law Implies Benford's Law For Distances To Galaxies, Theodore P. Hill, Ronald F. Fox
Research Scholars in Residence
A recent article by Alexopoulos and Leontsinis presented empirical evidence that the first digits of the distances from the Earth to galaxies are a reasonably good fit to the probabilities predicted by Benford’s law, the well known logarithmic statistical distribution of significant digits. The purpose of the present article is to give a theoretical explanation, based on Hubble’s law and mathematical properties of Benford’s law, why galaxy distances might be expected to follow Benford’s law. The new galaxy-distance law derived here, which is robust with respect to change of scale and base, to additive and multiplicative computational or observational errors, …
The Properties Of Post-Starburst Quasars Based On Optical Spectroscopy, Sabrina L. Cales, Michael S. Brotherton, Zhaohui Shang, Jessie C. Runnoe, Michael A. Dipompeo, Vardha Nicola Bennert, Gabriela Canalizo, Kyle D. Hiner, R. Stoll, Rajib Ganguly, Aleksandar Diamond-Stanic
The Properties Of Post-Starburst Quasars Based On Optical Spectroscopy, Sabrina L. Cales, Michael S. Brotherton, Zhaohui Shang, Jessie C. Runnoe, Michael A. Dipompeo, Vardha Nicola Bennert, Gabriela Canalizo, Kyle D. Hiner, R. Stoll, Rajib Ganguly, Aleksandar Diamond-Stanic
Physics
We present optical spectroscopy of a sample of 38 post-starburst quasars (PSQs) at z ~ 0.3, 29 of which have morphological classifications based on Hubble Space Telescope imaging. These broad-lined active galactic nuclei (AGNs) possess the spectral signatures of massive intermediate-aged stellar populations, making them potentially useful for studying connections between nuclear activity and host galaxy evolution. We model the spectra in order to determine the ages and masses of the host stellar populations, and the black hole masses and Eddington fractions of the AGNs. Our model components include an instantaneous starburst, a power law, and emission lines. We find …
Accretion Properties Of High- And Low-Excitation Young Radio Galaxies, Donghoon Son, Jong-Hak Woo, Sang Chul Kim, Hai Fu, Nozomu Kawakatu, Vardha N. Bennert, Tohru Nagao, Daeseong Park
Accretion Properties Of High- And Low-Excitation Young Radio Galaxies, Donghoon Son, Jong-Hak Woo, Sang Chul Kim, Hai Fu, Nozomu Kawakatu, Vardha N. Bennert, Tohru Nagao, Daeseong Park
Physics
Young radio galaxies (YRGs) provide an ideal laboratory to explore the connection between the accretion disk and radio jet thanks to their recent jet formation. We investigate the relationship between the emission-line properties, the black hole accretion rate, and the radio properties using a sample of 34 low-redshift (z < 0.4) YRGs. We classify YRGs as high-excitation galaxies (HEGs) and low-excitation galaxies (LEGs) based on the flux ratio of high-ionization to low-ionization emission lines. Using the Hα luminosities as a proxy of accretion rate, we find that HEGs in YRGs have ~1 dex higher Eddington ratios than LEGs in YRGs, suggesting that HEGs have a higher mass accretion rate or higher radiative efficiency than LEGs. In agreement with previous studies, we find that the luminosities of emission lines, in particular Hα, are correlated with radio core luminosity, suggesting that accretion and young radio activities are fundamentally connected.
A Local Baseline Of The Black Hole Mass Scaling Relations For Active Galaxies. Ii. Measuring Stellar Velocity Dispersion In Active Galaxies, Chelsea E. Harris, Vardha N. Bennert, Matthew W. Auger, Tommaso Treu, Jong-Hak Woo, Matthew A. Malkan
A Local Baseline Of The Black Hole Mass Scaling Relations For Active Galaxies. Ii. Measuring Stellar Velocity Dispersion In Active Galaxies, Chelsea E. Harris, Vardha N. Bennert, Matthew W. Auger, Tommaso Treu, Jong-Hak Woo, Matthew A. Malkan
Physics
We derive spatially resolved stellar kinematics for a sample of 84 out of 104 observed local (0.02 < z < 0.09) galaxies hosting type-1 active galactic nuclei (AGNs), based on long-slit spectra obtained at the 10 m W. M. Keck-1 Telescope. In addition to providing central stellar velocity dispersions, we measure major axis rotation curves and velocity dispersion profiles using three separate wavelength regions, including the prominent Ca H&K, Mg Ib, and Ca II NIR stellar features. In this paper, we compare kinematic measurements of stellar velocity dispersion obtained for different apertures, wavelength regions, and signal-to-noise ratios, and provide recipes to cross-calibrate the measurements reducing systematic effects to the level of a few percent. We also provide simple recipes based on readily observable quantities such as global colors and Ca H&K equivalent width that will allow observers of high-redshift AGN hosts to increase the probability of obtaining reliable stellar kinematic measurements from unresolved spectra in the region surrounding the Ca H&K lines. In subsequent papers in this series, we will combine this unprecedented spectroscopic data set with surface photometry and black hole mass measurements to study in detail the scaling relations between host galaxy properties and black hole mass.
The Lick Agn Monitoring Project 2011: Dynamical Modeling Of The Broad-Line Region In Mrk 50, Anna Pancoast, Brendon J. Brewer, Tommaso Treu, Aaron J. Barth, Vardha N. Bennert, Gabriela Canalizo, Alexei V. Filippenko, Elinor L. Gates, Jenny E. Greene, Weidong Li, Matthew A. Malkan, David J. Sand, Daniel Stern, Jong-Hak Woo, Roberto J. Assef, Hyun-Jin Bae, Tabitha Buehler, S. Bradley Cenko, Kelsey I. Clubb, Michael C. Cooper, Aleksandar M. Diamond-Stanic, Kyle D. Hiner, Sebastian F. Hönig, Michael D. Joner, Michael T. Kandrashoff, C. David Laney, Mariana S. Lazarova, A.M. Nierenberg, Dawoo Park, Jeffrey M. Silverman, Donghoon Son, Alessandro Sonnenfeld, Shawn J. Thorman, Erik J. Tollerud, Jonelle L. Walsh, Richard Walters
The Lick Agn Monitoring Project 2011: Dynamical Modeling Of The Broad-Line Region In Mrk 50, Anna Pancoast, Brendon J. Brewer, Tommaso Treu, Aaron J. Barth, Vardha N. Bennert, Gabriela Canalizo, Alexei V. Filippenko, Elinor L. Gates, Jenny E. Greene, Weidong Li, Matthew A. Malkan, David J. Sand, Daniel Stern, Jong-Hak Woo, Roberto J. Assef, Hyun-Jin Bae, Tabitha Buehler, S. Bradley Cenko, Kelsey I. Clubb, Michael C. Cooper, Aleksandar M. Diamond-Stanic, Kyle D. Hiner, Sebastian F. Hönig, Michael D. Joner, Michael T. Kandrashoff, C. David Laney, Mariana S. Lazarova, A.M. Nierenberg, Dawoo Park, Jeffrey M. Silverman, Donghoon Son, Alessandro Sonnenfeld, Shawn J. Thorman, Erik J. Tollerud, Jonelle L. Walsh, Richard Walters
Physics
We present dynamical modeling of the broad-line region (BLR) in the Seyfert 1 galaxy Mrk 50 using reverberation mapping data taken as part of the Lick AGN Monitoring Project (LAMP) 2011. We model the reverberation mapping data directly, constraining the geometry and kinematics of the BLR, as well as deriving a black hole mass estimate that does not depend on a normalizing factor or virial coefficient. We find that the geometry of the BLR in Mrk 50 is a nearly face-on thick disk, with a mean radius of 9.6+1.2 –0.9 light days, a width of the BLR of 6.9 …
The Lick Agn Monitoring Project 2011: Recalibrating Single-Epoch Virial Black Hole Mass Estimates, Daeseong Park, Jong-Hak Woo, Tommaso Treu, Aaron J. Barth, Misty C. Bentz, Vardha N. Bennert, Gabriela Canalizo, Alexei V. Filippenko, Elinor Gates, Jenny E. Greene, Matthew A. Malkan, Jonelle Walsh
The Lick Agn Monitoring Project 2011: Recalibrating Single-Epoch Virial Black Hole Mass Estimates, Daeseong Park, Jong-Hak Woo, Tommaso Treu, Aaron J. Barth, Misty C. Bentz, Vardha N. Bennert, Gabriela Canalizo, Alexei V. Filippenko, Elinor Gates, Jenny E. Greene, Matthew A. Malkan, Jonelle Walsh
Physics
We investigate the calibration and uncertainties of black hole (BH) mass estimates based on the single-epoch (SE) method, using homogeneous and high-quality multi-epoch spectra obtained by the Lick Active Galactic Nucleus (AGN) Monitoring Project for nine local Seyfert 1 galaxies with BH masses <108 M ☉. By decomposing the spectra into their AGNs and stellar components, we study the variability of the SE Hβ line width (full width at half-maximum intensity, FWHMHβ or dispersion, σHβ) and of the AGN continuum luminosity at 5100 Å (L 5100). From the distribution of the "virial products" ( …
The Lick Agn Monitoring Project 2011: Reverberation Mapping Of Markarian 50, Aaron J. Barth, Anna Pancoast, Shawn J. Thorman, Vardha N. Bennert, David J. Sand, Weidong Li, Gabriela Canalizo, Alexei V. Filippenko, Elinor L. Gates, Jenny E. Greene, Matthew A. Malkan, Daniel Stern, Tommaso Treu, Jong-Hak Woo, Roberto J. Assef, Hyun-Jin Bae, Brendon J. Brewer, Tabitha Buehler, S. Bradley Cenko, Kelsey I. Clubb, Michael C. Cooper, Aleksandar M. Diamond-Stanic, Kyle D. Hiner, Sebastian F. Hönig, Michael D. Joner, Michael T. Kandrashoff, C. David Laney, Mariana S. Lazarova, A. M. Nierenberg, Dawoo Park, Jeffrey M. Silverman, Donghoon Son, Alessandro Sonnenfeld, Erik J. Tollerud, Jonelle L. Walsh, Richard Walters, Robert L. Da Silva, Michele Fumagalli, Michael D. Gregg, Chelsea E. Harris, Eric Y. Hsiao, Jeffrey Lee, Liliana Lopez, Jacob Rex, Nao Suzuki, Jonathan R. Trump, David Tytler, Gábor Worseck, Hassan M. Yesuf
The Lick Agn Monitoring Project 2011: Reverberation Mapping Of Markarian 50, Aaron J. Barth, Anna Pancoast, Shawn J. Thorman, Vardha N. Bennert, David J. Sand, Weidong Li, Gabriela Canalizo, Alexei V. Filippenko, Elinor L. Gates, Jenny E. Greene, Matthew A. Malkan, Daniel Stern, Tommaso Treu, Jong-Hak Woo, Roberto J. Assef, Hyun-Jin Bae, Brendon J. Brewer, Tabitha Buehler, S. Bradley Cenko, Kelsey I. Clubb, Michael C. Cooper, Aleksandar M. Diamond-Stanic, Kyle D. Hiner, Sebastian F. Hönig, Michael D. Joner, Michael T. Kandrashoff, C. David Laney, Mariana S. Lazarova, A. M. Nierenberg, Dawoo Park, Jeffrey M. Silverman, Donghoon Son, Alessandro Sonnenfeld, Erik J. Tollerud, Jonelle L. Walsh, Richard Walters, Robert L. Da Silva, Michele Fumagalli, Michael D. Gregg, Chelsea E. Harris, Eric Y. Hsiao, Jeffrey Lee, Liliana Lopez, Jacob Rex, Nao Suzuki, Jonathan R. Trump, David Tytler, Gábor Worseck, Hassan M. Yesuf
Physics
The Lick AGN Monitoring Project 2011 observing campaign was carried out over the course of 11 weeks in spring 2011. Here we present the first results from this program, a measurement of the broad-line reverberation lag in the Seyfert 1 galaxy Mrk 50. Combining our data with supplemental observations obtained prior to the start of the main observing campaign, our data set covers a total duration of 4.5 months. During this time, Mrk 50 was highly variable, exhibiting a maximum variability amplitude of a factor of ~4 in the U-band continuum and a factor of ~2 in the Hβ …
The Relation Between Black Hole Mass And Host Spheroid Stellar Mass Out To Z~2, Vardha N. Bennert, Matthew A. Auger, Tommaso Treu, Jong-Hak Woo, Matthew A. Malkan
The Relation Between Black Hole Mass And Host Spheroid Stellar Mass Out To Z~2, Vardha N. Bennert, Matthew A. Auger, Tommaso Treu, Jong-Hak Woo, Matthew A. Malkan
Physics
We combine Hubble Space Telescope images from the Great Observatories Origins Deep Survey with archival Very Large Telescope and Keck spectra of a sample of 11 X-ray-selected broad-line active galactic nuclei in the redshift range 1 < z < 2 to study the black-hole-mass-stellar-mass relation out to a look-back time of 10 Gyr. Stellar masses of the spheroidal component (M sph, ) are derived from multi-filter surface photometry. Black hole masses (M BH) are estimated from the width of the broad Mg II emission line and the 3000 Å nuclear luminosity. Comparing with a uniformly measured local sample and taking into account selection effects, we find evolution in the form M BH/M sph, (1 + z)1.96 …
Hubble Space Telescope Imaging Of Post-Starburst Quasars, S. L. Cales, M. S. Brotherton, Zhaohui Shang, Vardha N. Bennert, G. Canalizo, R. Stoll, R. Ganguly, D. Vanden Berk, C. Paul, A. Diamond-Stanic
Hubble Space Telescope Imaging Of Post-Starburst Quasars, S. L. Cales, M. S. Brotherton, Zhaohui Shang, Vardha N. Bennert, G. Canalizo, R. Stoll, R. Ganguly, D. Vanden Berk, C. Paul, A. Diamond-Stanic
Physics
We present images of 29 post-starburst quasars (PSQs) from a Hubble Space Telescope (HST) Advanced Camera for Surveys (ACS) Wide Field Channel Snapshot program. These broadlined active galactic nuclei (AGNs) possess the spectral signatures of massive (M burst ~ 1010 M ☉), moderate-aged stellar populations (hundreds of Myr). Thus, their composite nature provides insight into the AGN-starburst connection. We measure quasar-to-host galaxy light contributions via semi-automated two-dimensional light profile fits of point-spread-function-subtracted images. We examine the host morphologies and model the separate bulge and disk components. The HST/ACS-F606W images reveal an equal number …
The Mass Of The Black Hole In Arp 151 From Bayesian Modeling Of Reverberation Mapping Data, Brendon J. Brewer, Tommaso Treu, Anna Pancoast, Aaron J. Barth, Vardha N. Bennert, Misty C. Bentz, Alexei V. Filippenko, Jenney E. Greene, Matthew A. Malkan, Jong-Hak Woo
The Mass Of The Black Hole In Arp 151 From Bayesian Modeling Of Reverberation Mapping Data, Brendon J. Brewer, Tommaso Treu, Anna Pancoast, Aaron J. Barth, Vardha N. Bennert, Misty C. Bentz, Alexei V. Filippenko, Jenney E. Greene, Matthew A. Malkan, Jong-Hak Woo
Physics
Supermassive black holes are believed to be ubiquitous at the centers of galaxies. Measuring their masses is extremely challenging yet essential for understanding their role in the formation and evolution of cosmic structure. We present a direct measurement of the mass of a black hole in an active galactic nucleus (Arp 151) based on the motion of the gas responsible for the broad emission lines. By analyzing and modeling spectroscopic and photometric time series, we find that the gas is well described by a disk or torus with an average radius of 3.99 ± 1.25 light days and an opening …
A Local Baseline Of The Black Hole Mass Scaling Relations For Active Galaxies. I. Methodology And Results Of Pilot Study, Vardha Nicola Bennert, Matthew W. Auger, Tommaso Treu, Jong-Hak Woo, Matthew A. Malkan
A Local Baseline Of The Black Hole Mass Scaling Relations For Active Galaxies. I. Methodology And Results Of Pilot Study, Vardha Nicola Bennert, Matthew W. Auger, Tommaso Treu, Jong-Hak Woo, Matthew A. Malkan
Physics
We present high-quality Keck/LRIS long-slit spectroscopy of a pilot sample of 25 local active galaxies selected from the SDSS (0.02 ≤z ≤ 0.1; M BH>107 M ☉) to study the relations between black hole mass (M BH) and host-galaxy properties. We determine stellar kinematics of the host galaxy, deriving stellar-velocity dispersion profiles and rotation curves from three spectral regions (including CaH&K, MgIb triplet, and Ca II triplet). In addition, we perform surface photometry on SDSS images, using a newly developed code for joint multi-band analysis. BH masses are estimated from the width of the …
The Lick Agn Monitoring Project: Alternate Routes To A Broad-Line Region Radius, Jenny E. Greene, Carol E. Hood, Aaron J. Barth, Vardha N. Bennert, Misty C. Benz, Alexei V. Filippenko, Elinor Gates, Matthew A. Malkan, Tommaso Treu, Jonelle L. Walsh, Jong-Hak Woo
The Lick Agn Monitoring Project: Alternate Routes To A Broad-Line Region Radius, Jenny E. Greene, Carol E. Hood, Aaron J. Barth, Vardha N. Bennert, Misty C. Benz, Alexei V. Filippenko, Elinor Gates, Matthew A. Malkan, Tommaso Treu, Jonelle L. Walsh, Jong-Hak Woo
Physics
It is now possible to estimate black hole (BH) masses across cosmic time, using broad emission lines in active galaxies. This technique informs our views of how galaxies and their central BHs coevolve. Unfortunately, there are many outstanding uncertainties associated with these "virial" mass estimates. One of these comes from using the accretion luminosity to infer a size for the broad-line region (BLR). Incorporating the new sample of low-luminosity active galaxies from our recent monitoring campaign at Lick Observatory, we recalibrate the radius-luminosity relation with tracers of the accretion luminosity other than the optical continuum. We find that the radius …
The Lick Agn Monitoring Project: Velocity-Delay Maps From The Maximum-Entropy Method For Arp 151, Misty C. Bentz, Keith Horne, Aaron J. Barth, Vardha Nicola Bennert, Gabriela Canalizo, Alexei V. Filippenko, Elinor L. Gates, Matthew A. Malkan, Takeo Minezaki, Tommaso Treu, Jong-Hak Woo, Jonelle L. Walsh
The Lick Agn Monitoring Project: Velocity-Delay Maps From The Maximum-Entropy Method For Arp 151, Misty C. Bentz, Keith Horne, Aaron J. Barth, Vardha Nicola Bennert, Gabriela Canalizo, Alexei V. Filippenko, Elinor L. Gates, Matthew A. Malkan, Takeo Minezaki, Tommaso Treu, Jong-Hak Woo, Jonelle L. Walsh
Physics
We present velocity-delay maps for optical H I, He I, and He II recombination lines in Arp 151, recovered by fitting a reverberation model to spectrophotometric monitoring data using the maximum-entropy method. H I response is detected over the range 0-15 days, with the response confined within the virial envelope. The Balmer-line maps have similar morphologies but exhibit radial stratification, with progressively longer delays for Hγ to Hβ to Hα. The He I and He II response is confined within 1-2 days. There is a deficit of prompt response in the Balmer-line cores but strong prompt response in the red …
The Lick Agn Monitoring Project: Reverberation Mapping Of Optical Hydrogen And Helium Recombination Lines, Misty C. Bentz, Jonelle L. Walsh, Aaron J. Barth, Yuzuru Yoshii, Jong-Hak Woo, Xiaofeng Wang, Tommaso Treu, Carol E. Thornton, Rachel A. Street, Thea N. Steele, Jeffrey M. Silverman, Frank J.D. Serduke, Yu Sakata, Takeo Minezaki, Matthew A. Malkan, Weidong Li, Nicholas Lee, Kyle D. Hiner, Marton G. Hidas, Jenny E. Greene, Elinor L. Gates, Mohan Ganeshalingam, Alexei V. Filippenko, Gabriela Canalizo, Vardha N. Bennert, Nairn Baliber
The Lick Agn Monitoring Project: Reverberation Mapping Of Optical Hydrogen And Helium Recombination Lines, Misty C. Bentz, Jonelle L. Walsh, Aaron J. Barth, Yuzuru Yoshii, Jong-Hak Woo, Xiaofeng Wang, Tommaso Treu, Carol E. Thornton, Rachel A. Street, Thea N. Steele, Jeffrey M. Silverman, Frank J.D. Serduke, Yu Sakata, Takeo Minezaki, Matthew A. Malkan, Weidong Li, Nicholas Lee, Kyle D. Hiner, Marton G. Hidas, Jenny E. Greene, Elinor L. Gates, Mohan Ganeshalingam, Alexei V. Filippenko, Gabriela Canalizo, Vardha N. Bennert, Nairn Baliber
Physics
We have recently completed a 64-night spectroscopic monitoring campaign at the Lick Observatory 3 m Shane telescope with the aim of measuring the masses of the black holes in 12 nearby (z < 0.05) Seyfert 1 galaxies with expected masses in the range ~106-107 M ☉ and also the well-studied nearby active galactic nucleus (AGN) NGC 5548. Nine of the objects in the sample (including NGC 5548) showed optical variability of sufficient strength during the monitoring campaign to allow for a time lag to be measured between the continuum fluctuations and the response to these fluctuations in the broad Hβ emission, which we have previously reported. We present …
The Lick Agn Monitoring Project: The M Bh-Σ* Relation For Reverberation-Mapped Active Galaxies, Jong-Hak Woo, Tommaso Treu, Aaron J. Barth, Shelley A. Wright, Jonelle L. Walsh, Misty C. Bentz, Paul Martini, Vardha N. Bennert, Gabriela Canalizo, Alexei V. Filippenko, Elinor Gates, Jenny Greene, Weidong Li, Matthew A. Malkan, Daniel Stern, Takeo Minezaki
The Lick Agn Monitoring Project: The M Bh-Σ* Relation For Reverberation-Mapped Active Galaxies, Jong-Hak Woo, Tommaso Treu, Aaron J. Barth, Shelley A. Wright, Jonelle L. Walsh, Misty C. Bentz, Paul Martini, Vardha N. Bennert, Gabriela Canalizo, Alexei V. Filippenko, Elinor Gates, Jenny Greene, Weidong Li, Matthew A. Malkan, Daniel Stern, Takeo Minezaki
Physics
To investigate the black hole mass versus stellar velocity dispersion (M BH-σ*) relation of active galaxies, we measured the velocity dispersions of a sample of local Seyfert 1 galaxies, for which we have recently determined black hole masses using reverberation mapping. For most objects, stellar velocity dispersions were measured from high signal-to-noise ratio optical spectra centered on the Ca II triplet region (~8500 Å), obtained at the Keck, Palomar, and Lick Observatories. For two objects, in which the Ca II triplet region was contaminated by nuclear emission, the measurement was based on high-quality H-band spectra …
Sdss J1254+0846: A Binary Quasar Caught In The Act Of Merging, Paul J. Green, Adam D. Myers, Wayne A. Barkhouse, John S. Mulchaey, Vardha N. Bennert, Thomas J. Cox, Thomas L. Aldcroft
Sdss J1254+0846: A Binary Quasar Caught In The Act Of Merging, Paul J. Green, Adam D. Myers, Wayne A. Barkhouse, John S. Mulchaey, Vardha N. Bennert, Thomas J. Cox, Thomas L. Aldcroft
Physics
We present the first luminous, spatially resolved binary quasar that clearly inhabits an ongoing galaxy merger. SDSS J125455.09+084653.9 and SDSS J125454.87+084652.1 (SDSS J1254+0846 hereafter) are two luminous z = 0.44 radio-quiet quasars, with a radial velocity difference of just 215 km s–1, separated on the sky by 21 kpc in a disturbed host galaxy merger showing obvious tidal tails. The pair was targeted as part of a complete sample of binary quasar candidates with small transverse separations drawn from SDSS DR6 photometry. We present follow-up optical imaging which shows broad, symmetrical tidal arm features spanning some 75 kpc …
The Lick Agn Monitoring Project: Broad-Line Region Radii And Black Hole Masses From Reverberation Mapping Of HSs, Misty C. Bentz, Jonelle L. Walsh, Aaron J. Barth, Nairn Baliber, Vardha N. Bennert, Gabriela Canalizo, Alexei V. Filippenko, Mohan Ganeshalingam, Elinor L. Gates, Jenny E. Greene, Marton G. Hidas, Kyle D. Hiner, Nicholas Lee, Weidong Li, Matthew A. Malkan, Takeo Minezaki, Yu Sakata, Frank J.D. Serduke, Jeffrey M. Silverman, Thea N. Steele, Daniel Stern, Rachel A. Street, Carol E. Thornton, Tommaso Treu, Xiaofeng Wang, Jong-Hak Woo, Yuzuru Yoshii
The Lick Agn Monitoring Project: Broad-Line Region Radii And Black Hole Masses From Reverberation Mapping Of HSs, Misty C. Bentz, Jonelle L. Walsh, Aaron J. Barth, Nairn Baliber, Vardha N. Bennert, Gabriela Canalizo, Alexei V. Filippenko, Mohan Ganeshalingam, Elinor L. Gates, Jenny E. Greene, Marton G. Hidas, Kyle D. Hiner, Nicholas Lee, Weidong Li, Matthew A. Malkan, Takeo Minezaki, Yu Sakata, Frank J.D. Serduke, Jeffrey M. Silverman, Thea N. Steele, Daniel Stern, Rachel A. Street, Carol E. Thornton, Tommaso Treu, Xiaofeng Wang, Jong-Hak Woo, Yuzuru Yoshii
Physics
We have recently completed a 64-night spectroscopic monitoring campaign at the Lick Observatory 3-m Shane telescope with the aim of measuring the masses of the black holes in 12 nearby (z < 0.05) Seyfert 1 galaxies with expected masses in the range ~106-107 M ☉ and also the well-studied nearby active galactic nucleus (AGN) NGC 5548. Nine of the objects in the sample (including NGC 5548) showed optical variability of sufficient strength during the monitoring campaign to allow for a time lag to be measured between the continuum fluctuations and the response to these fluctuations in the broad Hβ emission. We present here the light curves for all …
The Lick Agn Monitoring Project: Photometric Light Curves And Optical Variability Characteristics, Jonelle L. Walsh, Takeo Minezaki, Misty C. Bentz, Aaron J. Barth, Nairn Baliber, Weidong Li, Daniel Stern, Vardha Nicola Bennert, Timothy M. Brown, Gabriela Canalizo, Alexei V. Filippenko, Elinor L. Gates, Jenny E. Greene, Matthew A. Malkan, Yu Sakata, Rachel A. Street, Tommaso Treu, Jong-Hak Woo, Yuzuru Yoshii
The Lick Agn Monitoring Project: Photometric Light Curves And Optical Variability Characteristics, Jonelle L. Walsh, Takeo Minezaki, Misty C. Bentz, Aaron J. Barth, Nairn Baliber, Weidong Li, Daniel Stern, Vardha Nicola Bennert, Timothy M. Brown, Gabriela Canalizo, Alexei V. Filippenko, Elinor L. Gates, Jenny E. Greene, Matthew A. Malkan, Yu Sakata, Rachel A. Street, Tommaso Treu, Jong-Hak Woo, Yuzuru Yoshii
Physics
The Lick AGN Monitoring Project targeted 13 nearby Seyfert 1 galaxies with the intent of measuring the masses of their central black holes using reverberation mapping. The sample includes 12 galaxies selected to have black holes with masses roughly in the range 106-107 M ☉, as well as the well-studied active galactic nucleus (AGN) NGC 5548. In conjunction with a spectroscopic monitoring campaign, we obtained broadband B and V images on most nights from 2008 February through 2008 May. The imaging observations were carried out by four telescopes: the 0.76 m Katzman Automatic Imaging Telescope, the …
A Search For H2O Megamasers In High-Z Type-2 Active Galactic Nuclei, Vardha N. Bennert, Richard Barvainis, Christian Henkel, Robert Antonucci
A Search For H2O Megamasers In High-Z Type-2 Active Galactic Nuclei, Vardha N. Bennert, Richard Barvainis, Christian Henkel, Robert Antonucci
Physics
We report a search for H2O megamasers in 274 SDSS type-2 active galactic nuclei (AGNs; 0.3 <z< 0.83), half of which can be classified as type-2 quasi-stellar objects (QSOs) from their [O III] 5007 luminosity, using the Robert C. Byrd Green Bank Telescope (GBT) and the Effelsberg 100 m radio telescope. Apart from the detection of the extremely luminous water vapor megamaser SDSS J080430.99+360718.1, already reported by Barvainis & Antonucci, we do not find any additional line emission. This high rate of nondetections is compared to the water maser luminosity function created from the 78 water maser galaxies known to date and its extrapolation toward the higher luminosities of "gigamasers" that we would have been able to detect given the sensitivity of our survey. The properties of the known water masers are summarized and discussed with respect to the nature of high-z type-2 AGNs and megamasers in general. In the Appendix, we list 173 additional objects (mainly radio galaxies, but also QSOs and galaxies) that were observed with the GBT, the Effelsberg 100 m radio telescope, or Arecibo Observatory without leading to the detection of water maser emission.
First Results From The Lick Agn Monitoring Project: The Mass Of The Black Hole In Arp 151, Misty C. Bentz, Jonelle L. Walsh, Aaron J. Barth, Nairn Baliber, Nicola Bennert, Gabriela Canalizo, Alexei V. Filippenko, Mohan Ganeshalingam, Elinor L. Gates, Jenny E. Greene, Marton G. Hidas, Kyle D. Hiner, Nicholas Lee, Weidong Li, Matthew A. Malkan, Takeo Minezaki, Frank J.D. Serduke, Joshua H. Shiode, Jeffrey M. Silverman, Thea N. Steele, Daniel Stern, Rachel A. Street, Carol E. Thornton, Tommaso Treu, Xiaofeng Wang, Jong-Hak Woo, Yuzuru Yoshii
First Results From The Lick Agn Monitoring Project: The Mass Of The Black Hole In Arp 151, Misty C. Bentz, Jonelle L. Walsh, Aaron J. Barth, Nairn Baliber, Nicola Bennert, Gabriela Canalizo, Alexei V. Filippenko, Mohan Ganeshalingam, Elinor L. Gates, Jenny E. Greene, Marton G. Hidas, Kyle D. Hiner, Nicholas Lee, Weidong Li, Matthew A. Malkan, Takeo Minezaki, Frank J.D. Serduke, Joshua H. Shiode, Jeffrey M. Silverman, Thea N. Steele, Daniel Stern, Rachel A. Street, Carol E. Thornton, Tommaso Treu, Xiaofeng Wang, Jong-Hak Woo, Yuzuru Yoshii
Physics
We have recently completed a 64 night spectroscopic monitoring campaign at the Lick Observatory 3 m Shane telescope with the aim of measuring the masses of the black holes in 13 nearby (z < 0.05) Seyfert 1 galaxies with expected masses in the range ~106-107 M☉. We present here the first results from this project—the mass of the central black hole in Arp 151. Strong variability throughout the campaign led to an exceptionally clean Hβ lag measurement in this object of 4.25−0.66+0.68 days in the observed frame. Coupled with the width of the Hβ emission line in the variable spectrum, we determine a black …
Evidence For Merger Remnants In Early-Type Host Galaxies Of Low-Redshift Qsos, Nicola Bennert, Gabriela Canalizo, Bruno Jungwiert, Alan Stockton, François Schweizer, Chien Y. Peng, Mark Lacy
Evidence For Merger Remnants In Early-Type Host Galaxies Of Low-Redshift Qsos, Nicola Bennert, Gabriela Canalizo, Bruno Jungwiert, Alan Stockton, François Schweizer, Chien Y. Peng, Mark Lacy
Physics
We present results from a pilot HST ACS deep imaging study in broadband V of five low-redshift QSO host galaxies classified in the literature as ellipticals. The aim of our study is to determine whether these early-type hosts formed at high redshift and have since evolved passively, or whether they have undergone relatively recent mergers that may be related to the triggering of the nuclear activity. We perform two-dimensional modeling of the light distributions to analyze the host galaxies' morphology. We find that, while each host galaxy is reasonably well fitted by a de Vaucouleurs profile, the majority of them …
Spectacular Shells In The Host Galaxy Of The Qso Mc2 1635+119, Gabriela Canalizo, Nicola Bennert, Bruno Jungwiert, Alan Stockton, François Schweizer, Mark Lacy, Chien Peng
Spectacular Shells In The Host Galaxy Of The Qso Mc2 1635+119, Gabriela Canalizo, Nicola Bennert, Bruno Jungwiert, Alan Stockton, François Schweizer, Mark Lacy, Chien Peng
Physics
We present deep HST ACS images and Keck spectroscopy of MC2 1635+119, a QSO hosted by a galaxy previously classified as an undisturbed elliptical galaxy. Our new images reveal dramatic shell structure indicative of a merger event in the relatively recent past. The brightest shells in the central regions of the host are distributed alternately in radius, with at least two distinct shells on one side of the nucleus and three on the other, out to a distance of ~13 kpc. The light within the five shells comprises ~6% of the total galaxy light. Lower surface brightness ripples or tails …
Size And Properties Of The Narrow-Line Region In Seyfert-1 Galaxies From Spatially-Resolved Optical Spectroscopy, N. Bennert, B. Jungwiert, S. Komossa, M. Hass, R. Chini
Size And Properties Of The Narrow-Line Region In Seyfert-1 Galaxies From Spatially-Resolved Optical Spectroscopy, N. Bennert, B. Jungwiert, S. Komossa, M. Hass, R. Chini
Physics
Context.Spatially resolved emission-line spectroscopy is a powerful tool for determining the physical conditions in the narrow-line region (NLR) of active galactic nuclei (AGNs). We recently used optical long-slit spectroscopy to study the NLRs of a sample of six Seyfert-2 galaxies. We have shown that such an approach, in comparison to the commonly used [ ] narrow-band imaging alone, allows us to probe the size of the NLR in terms of AGN photoionisation. Moreover, several physical parameters of the NLR can be directly accessed. Aims.We here apply the same methods to study the NLR of six Seyfert-1 galaxies and …
Size And Properties Of The Narrow-Line Region In Seyfert-2 Galaxies From Spatially-Resolved Optical Spectroscopy, N. Bennert, B. Jungwiert, S. Komossa, M. Haas, R. Chini
Size And Properties Of The Narrow-Line Region In Seyfert-2 Galaxies From Spatially-Resolved Optical Spectroscopy, N. Bennert, B. Jungwiert, S. Komossa, M. Haas, R. Chini
Physics
Context. While [O III] narrow-band imaging is commonly used to measure the size of the narrow-line regions (NLRs) in active galactic nuclei (AGNs), it can be contaminated by emission from surrounding starbursts. Recently, we have shown that long-slit spectroscopy provides a valuable alternative approach to probe the size in terms of AGN photoionisation. Moreover, several parameters of the NLR can be directly accessed. Aims. We here apply the same methods developed and described for the Seyfert-2 galaxy NGC 1386 to study the NLR of five other Seyfert-2 galaxies by using high-sensitivity spatially-resolved optical spectroscopy obtained at the VLT and the …
The Radio Structure Of Radio-Quiet Quasars, C. Leipski, H. Falcke, N. Bennert, S. Hüttenmeister
The Radio Structure Of Radio-Quiet Quasars, C. Leipski, H. Falcke, N. Bennert, S. Hüttenmeister
Physics
Aims. We investigate the radio emitting structures of radio-quiet active galactic nuclei with an emphasis on radio-quiet quasars to study their connection to Seyfert galaxies. Methods. We present and analyse high-sensitivity VLA radio continuum images of 14 radio-quiet quasars and six Seyfert galaxies. Results. Many of the low redshift radio-quiet quasars show radio structures that can be interpreted as jet-like outflows. However, the detection rate of extended radio structures on arcsecond scales among our sample decreases with increasing redshift and luminosity, most likely due to a lack of resolution. The morphologies of the detected radio emission indicate strong interactions of …
[O Iii] Profile Substructure In Radio-Quiet Quasars, C. Leipski, N. Bennert
[O Iii] Profile Substructure In Radio-Quiet Quasars, C. Leipski, N. Bennert
Physics
Interactions between the radio jet and the optical emission of the narrow-line region (NLR) are a well known phenomenon in Seyfert galaxies. Here, we present the study of possible jet-NLR interactions in five radio-quiet PG quasars with double or triple radio structure. High spatial and spectral resolution observations were carried out in the H-[O III] 5007 wavelength range. In all cases, there is evidence for [O III] profile substructure (shoulders, subpeaks, blueshifted "broad'' components) with different clarity. To measure the velocity, line width, intensity, and location of these [O III] components, several Gaussians were fitted. Often, the substructures are more …
Size And Properties Of The Nlr In The Seyfert-2 Galaxy Ngc1386, N. Bennert, B. Jungwiert, S. Komossa
Size And Properties Of The Nlr In The Seyfert-2 Galaxy Ngc1386, N. Bennert, B. Jungwiert, S. Komossa
Physics
We study the narrow-line region (NLR) of the Seyfert-2 galaxy NGC 1386 by means of long-slit spectroscopy obtained with FORS1 at the VLT. We use the galaxy itself for subtracting the stellar template, applying reddening corrections to fit the stellar template to the spectra of the NLR. The continuum gets steadily redder towards the nucleus. The spatial distribution of the reddening derived from the Balmer decrement differs from the continuum reddening, indicating dust within the NLR with a varying column density along the line of sight. Using spatially resolved spectral diagnostics, we find a transition between central line ratios falling …