We investigate recent claims that the Hubble sequence of spiral galaxies is scale-free. Fundamental to this investigation is the fact that within the...

In this paper, we investigate whether the stellar initial mass function (IMF) of early-type galaxies depends on their host environment. To this purpose, we have...

We discuss the effects of microlensing on the broad emission lines (BELs) of QSOs in the light of recent determinations of the size of the broad-line region...

We study the influence of gravitational microlensing on the AGN Fe Kalpha line confirming that unexpected enhancements recently detected in the iron line of...

The lag associated with the main peak of the cross-correlation function of the two light curves arriving from a double-imaged quasar is usually identified with...

We discuss the different physical processes contributing to the infrared continuum of active galactic nuclei (AGNs), assuming that both photoionization from the...

We present subarcsecond resolution mid-infrared (mid-IR) photometry in the range from 8 to 20 μm of 18 nearby Seyfert galaxies, reporting high spatial...

We present subarcsecond resolution mid-infrared (mid-IR) photometry in the wavelength range from 8 to 20 μm of 18 Seyfert galaxies, reporting high spatial...

The complete mid- to far-infrared continuum energy distribution collected with the Infrared Space Observatory of the Seyfert 2 prototype NGC 5252 is presented...