Related papers: Aperture Effects on Spectroscopic Galaxy Activity …
We study the incidence of the underlying host galaxy light on the measured optical linear polarization of blazars. Our methodology consists of the implementation of simulated observations obtained under different atmospheric conditions,…
We present high-resolution HST images of all 35 AGNs with optical reverberation-mapping results, which we have modeled to create a nucleus-free image of each AGN host galaxy. From the nucleus-free images, we determine the host-galaxy…
We present the results of a set of mock experiments aimed at quantifying the accuracy of results derived from HI spectral line stacking experiments. We focus on the effects of spatial and spectral aperture sizes and redshift uncertainties…
The morphological classification of active galaxies may be affected by the presence of active galactic nuclei (AGN). In this paper, we provide the most detailed analysis on how different AGN contributions, from 5% to 75%, to the total…
Lightcurves have long been used to study stellar activity and have more recently become a major tool in the field of exoplanet research. We discuss the various ways in which stellar activity can influence transit lightcurves, and study the…
We use a complete sample of galaxies drawn from the SDSS to study how structure, star formation and nuclear activity depend on local density and on stellar mass. Local density is estimated by counting galaxies above a fixed absolute…
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…
Galaxy pairs are ideal sites in which to investigate the role of interaction on nuclear activity. For this reason we have undertaken a spectroscopic survey of a large homogeneous sample of galaxy pairs (UZC-BGP) and we present the results…
Active galactic nuclei (AGN) is one of the main drivers for transition from star-forming disk to passive spheroidal galaxies. However, the role of large-scale environment versus one-on-one interactions in triggering different types of AGN…
We analysed 385 galactic spectra from the Sloan Digital Sky Survey Data Release 7 (SDSS-DR7) that belong to the catalog of isolated pairs of galaxies by Karachentsev. The spectra corresponds to physical pairs of galaxies as defined by V…
How does the environment affect active galactic nucleus (AGN) activity? We investigated this question in an extinction-free way, by selecting 1120 infrared galaxies in the $AKARI$ North Ecliptic Pole Wide field at redshift $z$ $\leq$ 1.2. A…
Motivated by theoretical expectations that Nuclear Star Clusters (NSCs) in galactic centers may provide a favorable environment for super-massive black holes to form and/or efficiently grow, we set out to measure the fraction of nearby…
Accurate measurement of galaxy structures is a prerequisite for quantitative investigation of galaxy properties or evolution. Yet, the impact of galaxy inclination and dust on commonly used metrics of galaxy structure is poorly quantified.…
AGN feedback is believed to play an important role in shaping a variety of observed galaxy properties, as well as the evolution of their stellar masses and star formation rates. In particular, in the current theoretical paradigm of galaxy…
The existence of correlations between nuclear properties of galaxies, such as the mass of their central black holes, and larger scale features, like the bulge mass and luminosity, represent a fundamental constraint on galaxy evolution.…
We present the results of the classification of spectral activity types for 193 galaxies from a new sample of 49 compact groups of galaxies in the southern hemisphere (SCGs). This sample was selected in automated fashion from a digitized…
Our view of the properties of galaxies is strongly affected by the way in which we survey for them. I discuss some aspects of selection effects and methods to compensate for them. One result is an estimate of the surface brightness…
In order to study whether there is any correlation between nuclear activities, gas content, and the environment where galaxies reside, we have obtained optical and millimetric spectra for a well-defined sample of intermediate Hubble type…
We investigate the effects of halo ellipticity and alignment with larger-scale structure on the galaxy correlation function. We base our analysis on the galaxy formation models of Guo et al. (2011), run on the Millennium Simulations. We…
Transmission spectroscopy during planetary transits, which is based on the measurements of the variations of planet-to-star radius ratio as a function of wavelength, is a powerful technique to study the atmospheric properties of transiting…