Related papers: On the dichotomy of Seyfert 2 galaxies: intrinsic …
We investigate possible environmental and morphological trends in the $z\sim0$ bar fraction using two carefully selected samples representative of a low-density environment (the isolated galaxies from the AMIGA sample) and of a dense…
We present an analysis of six 12 um selected Seyfert 2 galaxies that have been reported to be unabsorbed in the X-ray. By comparing the luminosities of these galaxies in the mid-IR (12um), optical ([O III]) and hard X-ray (2-10 keV), we…
Narrow Line Seyfert 1 galaxies (NLS1) are very interesting objects which display peculiar properties when compared to their broad line analogues (BLS1). Although well studied in many wavebands, their behaviour at >10 keV is poorly studied…
This paper studies systematically, for the first time, the circumgalactic environment of bright IRAS galaxies as defined by Soifer et al. (1989). While the role of gravitational interaction for luminous and ultraluminous IRAS galaxies has…
We present new results of a program to study the detailed morphologies of galaxies in intermediate redshift clusters and hence understand the physical origin of the enhanced star formation in these environments at earlier epochs. Deep, high…
In this paper, we present our preliminary results on Seyfert galaxies with circumnuclear/nuclear starburst(SB) activity. We have searched the recent available literature and found 76 active galaxies with clear evidence of nuclear SB…
We use the recently discovered simple photometric parameter Central Intensity Ratio (CIR, Aswathy & Ravikumar 2018) determined for a sample of 57 nearby (z < 0.02) Seyfert galaxies to explore the central features of galaxies and their…
We have carried out an analysis of the radio and optical properties of a statistical sample of 45 Seyfert galaxies from the Palomar spectroscopic survey of nearby galaxies. We find that the space density of bright galaxies (-22 mag <=…
We discuss ROSAT HRI X-ray observations of 33 very nearby galaxies, sensitive to X-ray sources down to a luminosity of approximately 10^38 erg/s. The galaxies are selected from a complete, volume limited sample of 46 galaxies with d<7 Mpc…
We present the results of an optical spectroscopic survey designed to search for low-luminosity, "dwarf" Seyfert nuclei in a magnitude-limited sample of 486 bright, northern galaxies. Moderate-resolution spectra of exceptionally high…
Here we describe the \emph{Siding Spring Southern Seyfert Spectroscopic Snapshot Survey} (S7) and present results on 64 galaxies drawn from the first data release. The S7 uses the Wide Field Spectrograph (WiFeS) mounted on the ANU 2.3m…
We have collected emission line ([Oiii] 5007 and Halpha+[Nii]) and radio continuum images for a volume limited (cz <= 3600 km/s) sample of southern Seyfert galaxies. The optical data were obtained at ESO using the 2.2 m, NTT and 3.6 m…
We present a statistical study of a large, homogeneously analyzed sample of narrow-line Seyfert 1 (NLS1) galaxies, accompanied by a comparison sample of broad-line Seyfert 1 (BLS1) galaxies. Optical emission-line and continuum properties…
We used the $H\alpha$ images from a large sample of nearby late-type dwarf galaxies to investigate properties of their emission structure. The sample consists of three hundred galaxies of the irregular (Irr), Magellanic irregular (Im), blue…
We report on the unveiling of the nature of the unidentified X-ray source 3XMM J005450.3-373849 as a Seyfert-2 galaxy located behind the spiral galaxy NGC 300 using Hubble Space Telescope data, new spectroscopic Gemini observations and…
We present a near-infrared spectroscopic survey of narrow-line Seyfert 1 galaxies in the southern hemisphere (using the SOFI instrument on the ESO-NTT telescope), sampled from optical surveys. We examine the kinematics of the broad-line…
We study the neutral hydrogen properties of a sample of 20 bulgeless disk galaxies (Sd - Sdm Hubble types), an interesting class that can be used to constrain galaxy formation and evolution, especially the role of mergers versus internal…
Near-infrared spectroscopy (rest-frame 3700-6800 Angstroms) of eight high redshift powerful radio galaxies (HzPRGs) at z = 2.2-2.6 is presented. Strong forbidden lines and H-alpha emission were detected in all sources; the data show…
Narrow line Seyfert 1 (NLSy1) galaxies constitute a class of active galactic nuclei characterized by the full width at half maximum (FWHM) of the H$\beta$ broad emission line < 2000 km/s and the flux ratio of [O III] to H$\beta$ < 3. Their…
A pilot study with the powerful new backend of the Westerbork Synthesis Radio Telescope (WSRT) of two galaxy clusters at z=0.2 has revealed neutral hydrogen emission from 39 galaxies. The volume probed for each cluster is 1.7x10^4 Mpc^3,…