In this paper, we present an evolutionary unification scenario, involving supermassive black holes (SMBHs) and starbursts (SBs) with outflow (OF), that seems capable of explaining most of the observational properties (of at least part) of active galactic nuclei (AGN). The scenario includes a nuclear/circumnuclear SB closely associated with the AGN where the narrow-line region (NLR), broad-line region (BLR) and broad absorption line (BAL) region are produced in part by the OF process with shells and in compact supernova remnants (cSNRs). The OF process in BAL quasi-stellar objects (QSOs) with extreme infrared (IR) and Fe II emission is studied. In addition, the Fe II problem regarding the BLR of AGN is analysed. The correlations between the BAL, IR emission, Fe II intensity and the intrinsic properties of the AGN are not clearly understood. We suggest here that the behaviour of the BAL, IR and Fe II emission in AGN can be understood within an evolutionary and composite model for AGN. In our model, strong BAL systems and Fe II emission are present (and intense) in young IR objects. Parameters like the BALs, IR emission, Fe II/Hβ intensity ratio, Fe II equivalent width (EW), broad-line width, [O III] λ5007-A intensity and width, NLR size, X-ray spectral slope in radio quiet (RQ) AGN plus lobe separation, and lobe to core intensity ratio in radio loud (RL) AGN are proposed to be fundamentally time-dependent variables inside time-scales of the order of 10 8 yr. Orientation/obscuration effects take the role of a second parameter providing the segregation between Seyfert 1/Seyfert 2 galaxies (Sy1/Sy2) and broad-/narrow-line radio galaxies (BLRG/NLRG).

/pdf/evolutionary-unification-in-composite-active-galactic-nuclei-h1y1ao5iy5.pdf

Evolutionary unification in composite active galactic nuclei

During the commissioning phase of IUE several extragalactic objects were observed spectrally at low dispersion in the UV range lambda lambda 1150-3200: the Seyfert galaxies NGC4151 and NGC1068, the QSO 3C273, the BL Lacertae object B2 1101+38, the giant elliptical galaxy M87 and the spiral galaxy M81. The results obtained are presented and a preliminary analysis given for all six objects, discussing the continuous spectrum, extinction, emission line spectrum and absorption line spectrum, where possible for each case. Several new or confirmatory astrophysical results are obtained.

IUE observations of extragalactic objects

Apart from studies of the microwave background, direct exploration of the universe beyond the established redshifts of ordinary galaxies (z ~ 1) has, at least so far, had to rely on the detection and study of high redshift QSOs. This review covers work, principally on quasi-stellar objects with large redshifts, that has come to my attention in the interval May 1978 to February 1981. I have assumed, except where otherwise noted, that redshift is an indicator of distance in a zero-pressure Friedmann cosmology with zero cosmological constant, and zero deceleration parameter. I have taken the Hubble parameter as Ho = km s-1 Mpc-1. In this first section I shall give a rather detailed discussion of some of the techniques used to discover high-redshift QSOs, recent major surveys for high-redshift objects and efforts to quantify selection effects.

The Discovery and Observed Properties of QSOs at Large Redshifts — An Update

Models for the region emitting the forbidden and the permitted lines of Quasars and Seyfert nuclei are reviewed. First, the mode of energy supply is discussed, and it is concluded that, while the supply is predominantly radiative in the region emitting the forbidden lines, as generally assumed, it is probably partly kinetic in the region emitting the permitted lines. The models include stationary photoionized models, where the thermal equilibrium and the transfer are solved, models in which the transfer and the thermal equilibrium are not taken into account, and time dependent photoionized models. A brief discussion of the other kinds of possible models is given.

Self Consistent Models for the Emissive Regions of Quasars and Seyfert Nuclei

The profiles of spectral lines formed by pure resonance scattering in an extended, expanding envelope surrounding a continuum radiation source are calculated from a modification of Sobolev's escape-probability method. In contrast to earlier interpretations of the line profiles for the quasistellar object PHL 5200, the envelope expansion velocity is assumed to decrease outward; as a result better agreement is obtained between theory and observation. If the envelope is considered to be decelerated solely by the gravitational attraction of a nuclear region 5 pc in radius, then the mass of the nucleus would be 5 . 10/sup 10/ M/sub solar mass/.

Analysis of line profiles for the quasar PHL 5200. [Resonance scattering, escape probability]

The Optical Spectrum of the Seyfert Galaxy 3c 120

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The Optical Spectrum of the Seyfert Galaxy 3c 120