Related papers: On the morphology of sigma-drop galaxies
The mechanism causing breaks in the radial surface brightness distribution of spiral galaxies is not yet well known. Despite theoretical efforts, there is not a unique explanation for these features and the observational results are not…
The Halpha and mid-infrared mean disk surface brightnesses are compared in a sample of nearby spirals observed by ISOCAM. This shows that, in spiral disks, dust emission at 7 and 15 microns provides a reasonable star formation tracer. The…
We present results of an HST survey in Halpha and continuum filters of a sample of H_2O megamaser galaxies compiled by Braatz et al., all of which contain AGN. These observations allow us to study the AGN/host-galaxy connection, e.g. study…
Several authors recently explored the Black-Hole mass (M_BH) vs. stellar velocity dispersion (sigma_*) relationship for Narrow Line Seyfert 1 galaxies (NLS1s). Their results are more or less in agreement and seem to indicate that NLS1s fill…
We present the analysis of Halpha3, an Halpha imaging survey of galaxies selected from the HI ALFALFA Survey in the Coma Supercluster. By using the Halpha line as a tracer of the "instantaneous" star formation, complemented with optical…
We investigate the properties of the two-dimensional distribution and kinematics of ionised gas and stars in the central kiloparsecs of a matched sample of nearby active (Seyfert) and inactive galaxies, using the SAURON Integral Field Unit…
We present preliminary results from surface photometry of a sample of early-type galaxies observed with NICMOS on board HST in the F160W (H-band) filter. Dust is found to occur mostly in galaxies which possess unresolved nuclei, and in a…
We present 8-13 micron imaging and spectroscopy of 9 type 1 and 10 type 2 AGN obtained with the VLT/VISIR instrument at spatial resolution <100 pc. The emission from the host galaxy sources is resolved out in most cases. The silicate…
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$10\m\ (N magnitudes) published in the literature.…
This paper presents the first results of an Halpha imaging survey of galaxies in the central regions of the A2151 cluster. A total of 50 sources were detected in Halpha. The morphologies of the 43 H$\alpha$ selected galaxies range from…
We performed H-alpha imaging observations of 22 luminous infrared galaxies to investigate how the distribution of star-forming regions in these galaxies is related to galaxy interactions. Based on correlation diagrams between H-alpha flux…
The Unified Model of Active Galactic Nuclei (AGN) has provided a successful explanation for the observed diversity of AGN in the local Universe. However, recent analysis of multi-wavelength spectral and image data suggests that the Unified…
We combine ionized gas ([N II] 6583) and stellar central velocity dispersions for a sample of 345 galaxies, with and without active galactic nuclei (AGNs), to study the dynamical state of the nuclear gas and its physical origin. The gas…
Aims: Using a sample of 175 low-inclination galaxies from the S$^{4}$G, we investigate the origins of up-bending (Type III) breaks in the 3.6 $\mu$m surface brightness profiles of disk galaxies. Methods: We re-analyze a sample of previously…
We have conducted a study of optical and HI properties of spiral galaxies (size, luminosity, H-alpha flux distribution, circular velocity, HI gas mass) to investigate causes (e.g., nature versus nurture) for variation within the cluster…
We present scaling relations between structural properties of nuclear star clusters and their host galaxies for a sample of early-type dwarf galaxies observed as part of the Hubble Space Telescope (HST) Advanced Camera for Surveys (ACS)…
We describe the various Halpha morphologies of Virgo Cluster and isolated spiral galaxies, and associate the Halpha morphologies with the types of environmental interactions which have altered the cluster galaxies. The spatial distributions…
Gas flows in and out of galaxies through their circumgalactic medium (CGM) are poorly constrained and direct observations of this faint, diffuse medium remain challenging. We use a sample of five $z$ $\sim$ 1-2 galaxy counterparts to Damped…
We use state-of-the-art cosmological zoom simulations to explore the distribution of neutral gas in and around galaxies that gives rise to high column density \ion{H}{i} \mbox{Ly-$\alpha$} absorption (formally, sub-DLAs and DLAs) in the…
Current understanding of the secular evolution of galactic disks suggests that this process is dominated by two or more heating mechanisms, which increase the random motions of stars in the disk. In particular, the gravitational influence…