Related papers: The Diagnostics and Possible Evolution in Active G…
We report the results of a spectropolarimetric survey of the CfA and 12micron samples of Seyfert 2 galaxies (S2s). Polarized (hidden) broad line regions (HBLRs) are confirmed in a number of galaxies, and several new cases (F02581-1136, MCG…
In this third of a series of papers concerning active galaxies in the FIRST and Sloan Digital Sky Surveys, we analyze the spectroscopic and radio properties of a sample of narrow-line Active Galactic Nuclei (AGN), broad-line Seyfert I…
We present ISO PHOT-S spectra of four galaxies known or suspected to host a central AGN, selected from the initial Iras/Rosat sample of Boller et al. (1992). Two of them had no obvious Seyfert features in their previous optical spectra:…
Here we present the first results from the Siding Spring Southern Seyfert Spectroscopic Snapshot Survey (S7) which aims to investigate the physics of ~140 radio-detected southern active Galaxies with z<0.02 through Integral Field…
The ROSAT ALL Sky Survey Bright Source Catalogue (RASS-BSC) has been correlated with the Catalogue of Principal Galaxies (PGC) to identify new extragalactic counterparts. 550 reliable optical counterparts have been detected. We took optical…
Galaxy interactions are studied in terms of the starburst-Seyfert connection. The starburst requires a high rate of gas supply. Since the efficiency for supplying the gas is high in a galaxy interaction, although the companion is not…
Infrared photometry and later infrared spectroscopy provided powerful diagnostics to distinguish between the main emission mechanisms in galaxies: AGN and Starburst. After the pioneering work on infrared photometry with IRAS in the far-IR…
For the first time, a calibration between the HeI $\lambda5876$/H$\beta$ emission line ratio and the helium abundance $y$=12+log(He/H) for Narrow line regions (NLRs) of Seyfert~2 Active Galactic Nuclei (AGN) is proposed. In this context,…
This article focuses on certain variability and emission characteristics of Active Galactic Nuclei (AGN), especially their radio-loud subset consisting of quasars, BL Lacs and $\gamma$-ray detected narrow-line Seyfert 1 galaxies, all of…
We study the gas emission of galaxies with active star formation, consisting mostly of HII galaxies and Starbursts, as well as some Seyfert 2s, and determine chemical and physical parameters. The data consist of 19 high signal-to-noise…
We have measured the bar lengths and widths of 125 barred galaxies observed with CCDs. The dependence of bar strength (identified with bar axis ratio) on morphological type, nuclear activity, central and mid-bar surface brightness is…
We compare the arcsecond-scale circumnuclear radio continuum properties between five Seyfert and five starburst galaxies, concentrating on the search for any structures that could imply a spatial or causal connection between the nuclear…
Using the VLT together with the near infrared instrument ISAAC, we have obtained medium spectral and high spatial resolution observations of a sample of nearby Seyfert galaxies in the H-band. This band is particularly suited for stellar…
Galactic superwinds occur in almost all infrared-luminous galaxies with star formation rates (SFRs) above 10 M_sun/yr, as shown by studies of the NaI D interstellar absorption line. We demonstrate that this result also applies to…
We present the results of ASCA observations of a heterogenous sample of 15 spiral galaxies. 8 are LINERs or low-luminosity AGN (LLAGN), 5 are starburst galaxies and 2 are normal spiral galaxies. We find that in all cases the ASCA spectra…
We use 4 galaxies from the Calar Alto Legacy Integral Field Area (CALIFA) survey with clear signs of accretion onto supermassive black holes to investigate the relative contribution of star-formation and active galactic nucleus (AGN)…
It is not yet well known whether narrow line Seyfert 1 (NLS1) galaxies follow the $M_{BH} - \sigma_{\star}$ relation found for normal galaxies. Emission lines, such as [SII] or [OIII]$\lambda$5007, have been used as a surrogate of the…
The nature of the obscuring material in active galactic nuclei (AGN) can be studied by measuring changes in the line-of-sight column density, $N_{\rm H,los}$, over time. This can be accomplished by monitoring AGN over long periods of time…
We present an imaging survey of the CO(1--0), HCN(1--0), and HCO$^+$(1--0) lines in the nearby Seyfert galaxies using the Nobeyama Millimeter Array and RAINBOW Interferometer. Some of the observed Seyfert galaxies including NGC 1068, NGC…
We present high quality long-slit spectra for three nearby powerful radio galaxies 3C293, 3C305, PKS1345+12. These were taken with the aim of characterising the young stellar populations (YSP), and thereby investigating the evolution of the…