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Active galactic nuclei (AGNs) show a correlation between the size of thebroad line region (BLR) and the monochromatic continuum luminosity at 5100 \AA,allowing black hole mass estimation based on single-epoch spectra. However, thevalidity of the correlation is yet to be clearly tested for high-luminosityAGNs. We present the first reverberation-mapping results of the Seoul NationalUniversity AGN monitoring program (SAMP), which is designed to focus onluminous AGNs for probing the high end of the size-luminosity relation. Wereport time lag measurements of two AGNs, namely, 2MASS J10261389+5237510 andSDSS J161911.24+501109.2, using the light curves obtained over a $\sim$1000 dayperiod with an average cadence of $\sim$10 and $\sim$20 days, respectively forphotometry and spectroscopy monitoring. Based on a cross-correlation analysisand H$\beta$ line width measurements, we determine the H$\beta$ lag as$41.8^{+4.9}_{-6.0}$ and $52.6^{+17.6}_{-14.7}$ days in the observed-frame, andblack hole mass as $3.65^{+0.49}_{-0.57} \times 10^7 M_{\odot}$ and$23.02^{+7.81}_{-6.56} \times 10^7 M_{\odot}$, respectively for 2MASS J1026 andSDSS J1619.

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 Hβ line widths in mean and rms spectra. For the most highly variable AGNs we also measured broad Hβ line widths and velocity centroids from the nightly spectra. In four AGNs exhibiting the highest variability amplitudes, we detect anticorrelations between broad Hβ 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 Hβ velocity centroids can undergo substantial changes in response to continuum variations; in NGC 4593, the broad Hβ velocity shifted by ∼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.

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 Hβ 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 (τcen) of Fe II is longer than that of Hβ, 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 Véron-Cetty et al., we find τcen (Fe II)/τcen (Hβ) = 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. © 2013. The American Astronomical Society. All rights reserved.

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+1.2-1.1 light days, and a disk opening angle of 25 ± 10 deg above the plane. We also constrain the inclination angle to be 9+7-5 deg, close to face-on. Finally, the black hole mass of Mrk 50 is inferred to be log10(M BH/M = 7.57+0.44-0.27. By comparison to the virial black hole mass estimate from traditional reverberation mapping analysis, we find the normalizing constant (virial coefficient) to be log10 f = 0.78+0.44-0.27, consistent with the commonly adopted mean value of 0.74 based on aligning the M BH-σ* 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. © 2012. The American Astronomical Society. All rights reserved..

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 Mrk50. 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, Mrk50 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 line. Using standard cross-correlation techniques, we find that Hβ and Hγ lag the V-band continuum by τcen = 10.64+0.82- 0.93 and 8.43+1.30- 1.28days, respectively, while the lag of He II λ4686 is unresolved. The Hβ line exhibits a symmetric velocity-resolved reverberation signature with shorter lags in the high-velocity wings than in the line core, consistent with an origin in a broad-line region (BLR) dominated by orbital motion rather than infall or outflow. Assuming a virial normalization factor of f = 5.25, the virial estimate of the black hole mass is (3.2 ± 0.5) × 107 M ⊙. These observations demonstrate that Mrk50 is among the most promising nearby active galaxies for detailed investigations of BLR structure and dynamics. © 2011. The American Astronomical Society. All rights reserved.

The interplay between active galactic nuclei (AGNs) and their host galaxies' star-formation activities is one of the central topics in pursuing an understanding of galaxy evolution. With the advent of the Galaxy Evolution Explorer (GALEX), we have much more accurate information than ever about the recent star formation (RSF) histories of early-type galaxies within ~ 1.5 Gyr in the local universe. Using a subset of ~ 1000 GALEX/SDSS type 2 AGN-host early-type galaxies (E/S0) based on the emission-line ratio diagnosis, we explore how AGNs affect the RSF histories of the early-type hosts and vice versa. In this contribution, we present a preliminary yet interesting result on the intimate connection between AGN activity and the RSF histories of early-type galaxies. [ABSTRACT FROM PUBLISHER]