We review the variety of Active Galactic Nuclei (AGN) classes (so-calledAGN zoo") and classification schemes of galaxies by activity types based on their optical emission-line spectrum, as well as other parameters and other than optical wave-length ranges. A historical overview of discoveries of various types of active galaxies is given, including Seyfert galaxies, radio galaxies, QSOs, BL Lace...

In this paper we present new high resolution VLA 1.4 GHz radio continuum observations of five FIR bright CO-rich early-type galaxies and two dwarf earlytype galaxies. The position on the radio-FIR correlation combined with striking agreements in morphology between high resolution CO and radio maps show that the radio continuum is associated with star formation in at least four of the eight gala...

We have studied the radio and far-infrared (FIR) emission from 114 galaxies in the 7 nearest clusters (< 100 Mpc) with prominent X-ray emission to investigate the impact of the cluster environment on the star formation and AGN activity in the member galaxies. The X-ray selection criterion is adopted to focus on the most massive and dynamically relaxed clusters. A large majority of cluster galax...

We present a study on the effects of the intracluster medium (ICM) on the interstellar medium (ISM) of 10 Virgo cluster galaxies using Spitzer far-infrared (FIR) and VLA radio continuum imaging. Relying on the FIR-radio correlation within normal galaxies, we use our infrared data to create model radio maps which we compare to the observed radio images. For 6 of our sample galaxies we find regio...

We present optical identifications and redshifts for seventeen new high–redshift radio sources. Fifteen of these sources are radio galaxies; the remaining two are high–redshift, steep–spectrum, radio–loud quasars. These objects were discovered as part of an ongoing study of compact (θ < 10), moderately steep spectrum (α4.8 GHz 1.4 GHz > 0.75, Sν ∝ ν ) sources from the MIT – Green Bank (MG) radi...

We use K -band (2.1 μm) imaging to investigate the angular size and morphology of 10 6C radio galaxies, at redshifts 1 ≤ z ≤ 1.4. Two appear to be undergoing mergers, another contains two intensity peaks aligned with the radio jets, while the other seven appear consistent with being normal ellipticals in the K-band. Intrinsic half-light radii are estimated from the areas of each radio galaxy im...

We test the hypothesis that radio galaxies are a random subset of otherwise normal elliptical galaxies. Starting with the observed optical luminosity functions for elliptical galaxies, we show that the probability of an elliptical forming a radio source is a continuous, increasing function of optical luminosity, proportional to L. With this probability function and the luminosity function of no...

I have assembled a diverse sample of galaxies from the literature with far-ultraviolet (FUV), optical, infrared (IR) and radio luminosities to explore the calibration of radio-derived and IR-derived star formation (SF) rates, and the origin of the radio-IR correlation. By comparing the 8–1000μm IR, which samples dust-reprocessed starlight, with direct stellar FUV emission, I show that the IR tr...

Using recent high–resolution (<0.1”) radio observations of a large sample of Seyfert galaxies (Roy et al., 1994), we analyze the relations between their compact radio core emission and several nuclear and host galaxy properties (galaxy morphology, optical, infrared, X-ray, extended radio emissions, interaction parameters, and some emission line properties). We apply survival analysis techniques...

Three hundred fifty three radio sources from the NRAO VLA Sky Survey (NVSS) (Condon et al. 1998) and the FIRST Survey (White et al. 1997), are detected in the areas of 179 Shakhbazian Compact Groups (ShCGs) of galaxies. Ninety three of them are identified with galaxies in 74 ShCGs. Six radio sources have complex structure. The radio spectra of 22 sources are determined. Radio luminosities of ga...