相关论文: Analysis of nuclear activity of ten polar ring gal…
Based on SDSS data, we consider the fraction of active galactic nuclei among polar-ring galaxies. We have found evidence for an excess of Seyfert galaxies and LINERs among polar-ring galaxies compared to ordinary objects. The observed…
We analyze the idea that nuclear activity, either AGN or star formation, can be triggered by interactions, studying the percentage of active, HII and quiescent galaxies with companions. Our sample was selected from the Palomar survey, and…
In order to investigate the nuclear activity of galaxies residing in compact groups of galaxies, we present results of our optical spectroscopic program made at Okayama Astrophysical Observatory. We have performed optical spectroscopy of 69…
We analyse the level of nuclear activity in galaxies belonging to UZC-CGs. Spectra are available for 868 galaxies (90% of the whole catalog); 67 % of them show nuclear activity (AGN or Star formation). To carry out a detailed study about…
This paper is the last in a series, investigating the optical properties of a sample of mid-IR Warm Seyfert galaxies and of a control sample of mid-IR cold galaxies. In the present paper we parametrize the morphologies and interaction…
Active galaxies are often associated with starbursts, which are possible sources of fuelling for the nuclear black holes. By means of optical (3500-7500 A) spectroscopic and narrow-band photometric data (H_alpha+[NII]6548,6583 and…
Polar-ring galaxies are systems with two nearly orthogonal rotational axes, and are therefore clearly the result of galaxy-galaxy interactions. The host galaxies of polar rings are typically gas-poor early-type systems. The rings…
We are conducting the first systematic 3D spectroscopic imaging survey to quantify the properties of the atomic gas (HI) in a distance-limited sample of 28 Seyfert galaxies and a sample of 28 inactive control galaxies with well-matched…
This paper contains a list of new AGN candidates identified from the examination of 3500 optical spectra contained in the database of the Southern Sky Redshift Survey Extension (SSRS2). The classification of galaxies was done using standard…
A statistical study of the environment around Polar Ring Galaxies is presented. Two kinds of search are performed: 1) a study of the concentration and diameters of all the objects surrounding the Polar Rings, within a search field 5 times…
We have analyzed the frequency and properties of the nuclear activity in a sample of galaxies with circumnuclear rings and spirals (CNRs). This sample was compared with a control sample of galaxies with very similar global properties but…
Why are the nuclei of some galaxies more active than others? If most galaxies harbor a central massive black hole, the main difference is probably in how well it is fueled by its surroundings. We investigate the hypothesis that such a…
The VLA has been used to image HI in a heterogeneous sample of nine Seyferts as part of a continuing investigation of the role of galactic host gas in the triggering and fuelling of nuclear activity. Where previous single-dish observations…
We have obtained optical spectrophotometry of 11 HII regions in the polar ring of NGC 2685 (the Helix galaxy), and have used these data to study the physical characteristics of the polar-ring HII regions. The HII regions have normal spectra…
We report the results of spectroscopic observations of 8 southern polar-ring galaxies (PRGs), in the wavelength range 5900-7300 \AA. We fing that 5 out of 8 galaxies contain LINERs or Sy nuclei. Taking into consideration all PRGs with…
We report R~3000 VLT ISAAC K-band spectroscopy of the nuclei (i.e. central 100-300pc) of 9 galaxies hosting an active galactic nucleus. For 5 of these we also present spectra of the circumnuclear region out to 1kpc. We have measured a…
We observed 37 AGN candidates and classified them on the basis of their spectroscopic properties; three are confirmed QSOs, one is a BL Lac object, nine are Seyfert 1 galaxies, four Seyfert 2s, while twenty are HII regions.
We use the sample of emission-line nuclei derived from a recently completed optical spectroscopic survey of nearby galaxies to quantify the incidence of local (z = 0) nuclear activity. Consistent with previous studies, we find detectable…
We present a spectroscopic study of the incidence of AGN nuclear activity in two samples of isolated galaxies (Karachentseva, V.E. & Varela, J.). Our results show that the incidence of non-thermal nuclear activity is about 43% and 31% for…
We examine the 10\m\ emission of the central regions of 281 spiral galaxies, after having compiled all ground-based, small-aperture ($\sim$5") broad-band photometric observations at \l$\sim$10\m\ (N magnitudes) published in the literature.…