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We present 432 low-dispersion optical spectra of 32 Type Ia supernovae (SNe Ia) that also have well-calibrated light curves. The coverage ranges from 6 epochs to 36 epochs of spectroscopy. Most of the data were obtained with the 1.5 m Tillinghast telescope at the F. L. Whipple Observatory with typical wavelength coverage of 3700-7400 Å and a resolution of ∼7 Å. The earliest spectra are 13 days before B-band maximum; two-thirds of the SNe were observed before maximum brightness. Coverage for some SNe continues almost to the nebular phase. The consistency of the method of observation and the technique of reduction makes this an ideal data set for studying the spectroscopic diversity of SNe Ia.

We present Herschel (PACS and SPIRE) far-infrared (FIR) photometry of a complete sample of z > 1 3CR sources, from the Herschel guaranteed time project The Herschel Legacy of distant radio-loud AGN. Combining these with existing Spitzer photometric data, we perform an infrared (IR) spectral energy distribution (SED) analysis of these landmark objects in extragalactic research to study the star formation in the hosts of some of the brightest active galactic nuclei (AGN) known at any epoch. Accounting for the contribution from an AGN-powered warm dust component to the IR SED, about 40% of our objects undergo episodes of prodigious, ULIRGstrength star formation, with rates of hundreds of solar masses per year, coeval with the growth of the central supermassive black hole. Median SEDs imply that the quasar and radio galaxy hosts have similar FIR properties, in agreement with the orientationbased unification for radio-loud AGN. The star-forming properties of the AGN hosts are similar to those of the general population of equally massive non-AGN galaxies at comparable redshifts, thus there is no strong evidence of universal quenching of star formation (negative feedback) within this sample. Massive galaxies at high redshift may be forming stars prodigiously, regardless of whether their supermassive black holes are accreting or not.

The concept of the quasar main sequence is very attractive since it stresses correlations between various parameters and implies the underlying simplicity. In the optical plane defined by the width of the Hβ line and the ratio of the equivalent width of the Fe II to Hβ observed objects form a characteristic pattern. In this paper, we use a physically motivated model to explain the distribution of quasars in the optical plane. Continuum is modelled as an accretion disk with a hard X-ray power law uniquely tight to the disk at the basis of observational scaling, and the Broad Line Region distance is determined also from observational scaling. We perform the computations of the FeII and Hβ line production with the code CLOUDY. We have only six free parameters for an individual source: maximum temperature of the accretion disk, Eddington ratio, cloud density, cloud column density, microturbulence, and iron abundance, and only the last four remain as global parameters in our modelling of the whole sequence. Our theoretically computed points cover well the optical plane part populated with the observed quasars, particularly if we allow for super-Solar abundance of heavy elements. Explanation of the exceptionally strong Fe II emitter requires a stronger contribution from the dark sides of the clouds. Analyzing the way how our model covers the optical plane we conclude that there is no single simple driver behind the sequence, as neither the Eddington ratio nor broad band spectrum shape plays the dominant role. Also, the role of the viewing angle in providing the dispersion of the quasar main sequence is apparently not as strong as expected.

Hard X-ray selection is, arguably, the optimal method for defining a representative sample of active galactic nuclei (AGN). Hard X-rays are unbiased by the affects of obscuration and reprocessing along the line-of-sight intrinsic/external to the AGN which result in unknown fractions of the population being missed from traditional optical/soft-X-ray samples. We present the farinfrared (IR) observations of 21 hard X-ray selected AGN from the HEAO-1 A2 sample observed with ISO. We characterize the far-infrared (IR) continua of these X-ray selected AGN, compare them with those of various radio and optically selected AGN samples and with models for an AGN-heated, dusty disk. The X-ray selected AGN show broad, warm IR continua covering a wide temperature range (∼ 20 − 1000 K in a thermal emission scenario). Where a far-IR turnover is clearly observed, the slopes are < 2.5 in all but three cases so that non-thermal emission remains a possibility, although the presence of cooler dust resulting in a turn-over at wavelengths longwards of the ISO range is considered more likely. The sample also shows a wider range of optical/UV shapes than the optically/radio-selected samples, extending to redder near-IR colors. The bluer objects are type 1 Seyferts, while the redder AGN are mostly intermediate or type 2 Seyferts. This is consistent with a modified unification model in which obscuration increases as we move from a face-on towards more edge-on line-of-sight (l.o.s.) However, this relation does not extend to the mid-infrared as the 25µm/60µm ratios are similar in Seyferts with differing type and optical/UV reddening. The resulting limits on the column density of obscuring material through which we are viewing the redder AGN (N H ∼ 10 22 cm −2 ) are inconsistent with standard optically thick torus models (N H ∼ 10 24 cm −2 ) and simple unification models. Instead our results support more complex models in which the amount of obscuring material increases with viewing angle and may be clumpy. Such a scenario, already suggested by differing optical/near-IR spectroscopic and X-ray AGN classifications, allows for different amounts of obscuration of the continuum emission in different wavebands and of the broad emission line region which, in turn, results in a mixture of behaviors for AGN with similar optical emission line classifications. The resulting decrease in the optical depth of the obscuring material also allows the AGN to heat more dust at larger radial distances. We show that an AGN-heated, flared, dusty disk with mass ∼ 10 9 M and size∼few hundred pc is able to generate optical−far-IR spectral energy distributions (SEDs) which reproduce the wide range of SEDs present in our sample with no need for an additional starburst component to generate the long-wavelength, cooler part of the IR continuum.