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THE LICK AGN MONITORING PROJECT 2011: DYNAMICAL MODELING OF THE BROAD-LINE REGION IN Mrk 50
Pancoast, Anna,Brewer, Brendon J.,Treu, Tommaso,Barth, Aaron J.,Bennert, Vardha N.,Canalizo, Gabriela,Filippenko, Alexei V.,Gates, Elinor L.,Greene, Jenny E.,Li, Weidong,Malkan, Matthew A.,Sand, David IOP Publishing 2012 The Astrophysical journal Vol.754 No.1
<P>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(-0.9)(+1.2) light days, a width of the BLR of 6.9(-1.1)(+1.2) light days, and a disk opening angle of 25 +/- 10 deg above the plane. We also constrain the inclination angle to be 9(-5)(+7) deg, close to face-on. Finally, the black hole mass of Mrk 50 is inferred to be log(10)(M-BH/M-circle dot) = 7.57(-0.27)(+0.44). By comparison to the virial black hole mass estimate from traditional reverberation mapping analysis, we find the normalizing constant (virial coefficient) to be log(10) f = 0.78(-0.27)(+0.44), consistent with the commonly adopted mean value of 0.74 based on aligning the M-BH-sigma* relation for active galactic nuclei and quiescent galaxies. While our dynamical model includes the possibility of a net inflow or outflow in the BLR, we cannot distinguish between these two scenarios.</P>
THE LICK AGN MONITORING PROJECT 2011: Fe II REVERBERATION FROM THE OUTER BROAD-LINE REGION
Barth, Aaron J.,Pancoast, Anna,Bennert, Vardha N.,Brewer, Brendon J.,Canalizo, Gabriela,Filippenko, Alexei V.,Gates, Elinor L.,Greene, Jenny E.,Li, Weidong,Malkan, Matthew A.,Sand, David J.,Stern, Dan IOP Publishing 2013 The Astrophysical journal Vol.769 No.2
<P>The prominent broad Fe II emission blends in the spectra of active galactic nuclei have been shown to vary in response to continuum variations, but past attempts to measure the reverberation lag time of the optical Fe II lines have met with only limited success. Here we report the detection of Fe II reverberation in two Seyfert 1 galaxies, NGC 4593 and Mrk 1511, based on data from a program carried out at Lick Observatory in Spring 2011. Light curves for emission lines including H beta and Fe II were measured by applying a fitting routine to decompose the spectra into several continuum and emission-line components, and we use cross-correlation techniques to determine the reverberation lags of the emission lines relative to V-band light curves. In both cases, the measured lag (tau(cen)) of Fe II is longer than that of H beta, although the inferred lags are somewhat sensitive to the choice of Fe II template used in the fit. For spectral decompositions done using the Fe II template of Veron-Cetty et al., we find tau(cen)(Fe II)/tau(cen)(H beta) = 1.9 +/- 0.6 in NGC 4593 and 1.5 +/- 0.3 in Mrk 1511. The detection of highly correlated variations between Fe II and continuum emission demonstrates that the Fe II emission in these galaxies originates in photoionized gas, located predominantly in the outer portion of the broad-line region.</P>
The Lick AGN Monitoring Project 2011: Dynamical Modeling of the Broad-line Region
Williams, Peter R.,Pancoast, Anna,Treu, Tommaso,Brewer, Brendon J.,Barth, Aaron J.,Bennert, Vardha N.,Buehler, Tabitha,Canalizo, Gabriela,Cenko, S. Bradley,Clubb, Kelsey I.,Cooper, Michael C.,Filippen American Astronomical Society 2018 The Astrophysical journal Vol.866 No.2
ACTIVE GALACTIC NUCLEUS BLACK HOLE MASS ESTIMATES IN THE ERA OF TIME DOMAIN ASTRONOMY
Kelly, Brandon C.,Treu, Tommaso,Malkan, Matthew,Pancoast, Anna,Woo, Jong-Hak IOP Publishing 2013 The Astrophysical journal Vol.779 No.2
<P>We investigate the dependence of the normalization of the high-frequency part of the X-ray and optical power spectral densities (PSDs) on black hole mass for a sample of 39 active galactic nuclei (AGNs) with black hole masses estimated from reverberation mapping or dynamical modeling. We obtained new Swift observations of PG 1426+015, which has the largest estimated black hole mass of the AGNs in our sample. We develop a novel statistical method to estimate the PSD from a light curve of photon counts with arbitrary sampling, eliminating the need to bin a light curve to achieve Gaussian statistics, and we use this technique to estimate the X-ray variability parameters for the faint AGNs in our sample. We find that the normalization of the high-frequency X-ray PSD is inversely proportional to black hole mass. We discuss how to use this scaling relationship to obtain black hole mass estimates from the short timescale X-ray variability amplitude with precision similar to 0.38 dex. The amplitude of optical variability on timescales of days is also anticorrelated with black hole mass, but with larger scatter. Instead, the optical variability amplitude exhibits the strongest anticorrelation with luminosity. We conclude with a discussion of the implications of our results for estimating black hole mass from the amplitude of AGN variability.</P>
THE MASS OF THE BLACK HOLE IN Arp 151 FROM BAYESIAN MODELING OF REVERBERATION MAPPING DATA
Brewer, Brendon J.,Treu, Tommaso,Pancoast, Anna,Barth, Aaron J.,Bennert, Vardha N.,Bentz, Misty C.,Filippenko, Alexei V.,Greene, Jenny E.,Malkan, Matthew A.,Woo, Jong-Hak IOP Publishing 2011 ASTROPHYSICAL JOURNAL LETTERS - Vol.733 No.2
<P>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 angle of 68.9(-17.2)(+21.4) deg, viewed at an inclination angle of 67.8 +/- 7.8 deg (that is, closer to face-on than edge-on). The black hole mass is inferred to be 10(6.51 +/- 0.28) M-circle dot. The method is fully general and can be used to determine the masses of black holes at arbitrary distances, enabling studies of their evolution over cosmic time.</P>
Park, Daeseong,Barth, Aaron J.,Woo, Jong-Hak,Malkan, Matthew A.,Treu, Tommaso,Bennert, Vardha N.,Assef, Roberto J.,Pancoast, Anna American Astronomical Society 2017 The Astrophysical journal Vol.839 No.2
<P>We provide an updated calibration of C IV lambda 1549 broad emission line-based single-epoch (SE) black hole (BH) mass estimators for active galactic nuclei (AGNs) using new data for six reverberation-mapped AGNs at redshift z = 0.005-0.028 with BH masses (bolometric luminosities) in the range 10(6.5)-10(7.5) M-circle dot (10(41.7)-10(43.8) erg s(-1)). New rest-frame UV-to-optical spectra covering 1150-5700 angstrom for the six AGNs were obtained with the Hubble Space Telescope (HST). Multicomponent spectral decompositions of the HST spectra were used to measure SE emission-line widths for the C IV, MgII, and H beta lines, as well as continuum luminosities in the spectral region around each line. We combine the new data with similar measurements for a previous archival sample of 25 AGNs to derive the most consistent and accurate calibrations of the C IV-based SE BH mass estimators against the H beta reverberation-based masses, using three different measures of broad-line width: full. width at half maximum (FWHM), line dispersion (sigma line), and mean absolute deviation (MAD). The newly expanded sample at redshift wz = 0.005-0.234 covers a dynamic range in BH mass (bolometric luminosity) of logM(BH)/M-circle dot = 6.5-9.1 (log L-bol/ erg s(-1) = 41.7-46.9), and we derive the new C IV-based mass estimators using a Bayesian linear regression analysis over this range. We generally recommend the use of sigma line or MAD rather than FWHM to obtain a less biased velocity measurement of the C IV emission line, because its narrow-line component contribution is difficult to decompose from the broad-line profile.</P>
THE LICK AGN MONITORING PROJECT 2011: SPECTROSCOPIC CAMPAIGN AND EMISSION-LINE LIGHT CURVES
Barth, Aaron J.,Bennert, Vardha N.,Canalizo, Gabriela,Filippenko, Alexei V.,Gates, Elinor L.,Greene, Jenny E.,Li, Weidong,Malkan, Matthew A.,Pancoast, Anna,Sand, David J.,Stern, Daniel,Treu, Tommaso,W IOP Publishing 2015 The Astrophysical journal Supplement series Vol.217 No.2
<P>In the Spring of 2011 we carried out a 2.5 month reverberation mapping campaign using the 3 m Shane telescope at Lick Observatory, monitoring 15 low-redshift Seyfert 1 galaxies. This paper describes the observations, reductions and measurements, and data products from the spectroscopic campaign. The reduced spectra were fitted with a multicomponent model in order to isolate the contributions of various continuum and emission-line components. We present light curves of broad emission lines and the active galactic nucleus (AGN) continuum, and measurements of the broad H beta line widths in mean and rms spectra. For the most highly variable AGNs we also measured broad Ha line widths and velocity centroids from the nightly spectra. In four AGNs exhibiting the highest variability amplitudes, we detect anticorrelations between broad H beta width and luminosity, demonstrating that the broad-line region 'breathes' on short timescales of days to weeks in response to continuum variations. We also find that broad Ha velocity centroids can undergo substantial changes in response to continuum variations; in NGC 4593, the broad H beta velocity shifted by similar to 250 km s(-1) over a 1 month period. This reverberation-induced velocity shift effect is likely to contribute a significant source of confusion noise to binary black hole searches that use multi-epoch quasar spectroscopy to detect binary orbital motion. We also present results from simulations that examine biases that can occur in measurement of broad-line widths from rms spectra due to the contributions of continuum variations and photon-counting noise.</P>