After the All-Sky Automated Survey for SuperNovae (ASAS-SN) discovered a significant brightening of the inner region of NGC 2617, we began a ∼ 70 day photometric and spectroscopic monitoring campaign from the X-ray through near-infrared (NIR) wavelengths. We report that NGC 2617 went through a dramatic outburst, during which its X-ray flux increased by over an order of magnitude followed by an increase of its optical/ultraviolet (UV) continuum flux by almost an order of magnitude. NGC 2617, classified as a Seyfert 1.8 galaxy in 2003, is now a Seyfert 1 due to the appearance of broad optical emission lines and a continuum blue bump. Such "changing look Active Galactic Nuclei (AGN)" are rare and provide us with important insights about AGN physics. Based on the Hβ line width and the radius-luminosity relation, we estimate the mass of central black hole to be (4 ± 1) × 10 7 M ⊙ . When we crosscorrelate the light curves, we find that the disk emission lags the X-rays, with the lag becoming longer as we move from the UV (2 − 3 days) to the NIR (6 − 9 days). Also, the NIR is more heavily temporally smoothed than the UV. This can largely be explained by a simple model of a thermally emitting thin disk around a black hole of the estimated mass that is illuminated by the observed, variable X-ray fluxes.

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We report Swift observations of a sample of 92 bright soft X-ray selected active galactic nuclei (AGN). This sample represents the largest number of AGN observed to study the spectral energy distribution (SED) of AGN with simultaneous optical/UV and X-ray data. The principal motivation of this study is to understand the SEDs of AGN in the optical/UV to X-ray regime and to provide bolometric corrections which are important in determining the Eddington ratio L/L Edd . In particular, we rigorously explore the dependence of the UV-EUV contribution to the bolometric correction on the assumed EUV spectral shape. We find strong correlations of the spectral slopes α X and α UV with L/L Edd . Although Narrow-Line Seyfert 1 galaxies (NLS1s) have steeper α X and higher L/L Edd than Broad-Line Seyfert 1 galaxies (BLS1s), their optical/UV to X-ray spectral slopes α ox and optical/UV slopes α UV are very similar. The mean SED of NLS1s shows that in general this type of AGN appears to be fainter in the UV and at hard X-ray energies than BLS1s. We find a strong correlation between α X and α UV for AGN with X-ray spectral slopes α X <1.6. For AGN with steeper X-ray spectra, both this relation and the relation between α X and L/L Edd break down. At α X ≈1.6, L/L Edd reaches unity. We note an offset in the α UV -L/L Edd relation between NLS1s and BLS1s. We argue that α UV is a good estimator of L/L Edd and suggest that α UV can be used to estimate L/L Edd in high-redshift QSOs. Although NLS1s appear to be highly variable in X-rays they only vary marginally in the UV.

We present the final results from a high sampling rate, multi-month, spectrophotometric reverberation mapping campaign undertaken to obtain either new or improved Hβ reverberation lag measurements for several relatively low-luminosity active galactic nuclei (AGNs). We have reliably measured the time delay between variations in the continuum and Hβ emission line in six local Seyfert 1 galaxies. These measurements are used to calculate the mass of the supermassive black hole at the center of each of these AGNs. We place our results in context to the most current calibration of the broad-line region (BLR) R BLR -L relationship, where our results remove outliers and reduce the scatter at the low-luminosity end of this relationship. We also present velocity-resolved Hβ time-delay measurements for our complete sample, though the clearest velocity-resolved kinematic signatures have already been published.

We present modeling to explore the conditions of the broad-line emitting gas in two extreme Narrow-line Seyfert 1 galaxies, using the observational results described in the first paper of this series. Photoionization modeling using Cloudy was conducted for the broad, blueshifted wind lines and the narrow, symmetric, rest-wavelength-centered disk lines separately. A broad range of physical conditions were explored for the wind component, and a figure of merit was used to quantitatively evaluate the simulation results. Of the three minima in the figure-of-merit parameter space, we favor the solution characterized by an X-ray weak continuum, elevated abundances, a small column density (log(N H ) ≈ 21.4), relatively high ionization parameter (log(U ) ≈ −1.2-−0.2), a wide range of densities (log(n) ≈ 7-11), and a covering fraction of ∼ 0.15. The presence of low-ionization emission lines implies the disk component is optically thick to the continuum, and the Si III]/C III] ratio implies a density of 10 10 -10 10.25 cm −3 . A low ionization parameter (log(U ) = −3) is inferred for the intermediate-ionization lines, unless the continuum is "filtered" through the wind before illuminating the intermediateline emitting gas, in which case log(U ) = −2.1. The location of the emission regions was inferred from the photoionization modeling and a simple "toy" dynamical model. A large black hole mass (1.3 × 10 8 M ⊙ ) radiating at 11% of the Eddington luminosity is consistent with the kinematics of both the disk and wind lines, and an emission radius of ∼ 10 4 R S is inferred for both. We compare these results with previous work and discuss implications. 3 We do not know with certainty the geometrical and physical origin of the emission lines in the objects we are -3 -The strongly blueshifted C IV profile suggested that it is dominated by emission in the wind. Following Baldwin et al. (1996), we used the C IV profile to develop a template for the wind. We then used this template, plus a narrow and symmetric component representing the disk emission, to model the other bright emission lines. We inferred that the high-ionization lines N V and He II are also dominated by wind emission, and a part of Lyα is emitted in the wind. A part of Lyα and the intermediate-and low-ionization lines Al III, Si III], C III], and Mg II are dominated by disk emission. The 1400Å feature, comprised of O IV] and Si IV was difficult to model; however, it appears to include both disk and wind emission. discussing here. However, for simplicity, we refer to the highly blueshifted high-ionization lines as originating in the "wind", and the narrow, symmetric low-ionization lines as originating in the "disk".