Related papers: Molecular Hydrogen Excitation around Active Galact…
We present the detection of four rotational emission lines of water vapor, from energy levels Eu/k= 101 - 454 K, in the gravitationally lensed z=3.9 QSO host galaxy APM08279+5255. While the lowest H2O lines are collisionally excited in…
We have mapped the H_2 v=1-0 S(1) (\lambda=2.1215 \micron) emission line along a 400 pc long strip and in a 50 pc region in the Galactic center. There is H_2 emission throughout the surveyed region. The typical de-reddened (A_K = 2.5 mag)…
We present the first results of an analysis of the properties of the molecular gas in the nuclear regions (r < 300 pc) of a sample of six nearby galaxies, based on new high spatial resolution observations obtained in the K-band with the…
We discuss the interstellar absorption from many atomic and molecular species seen in high-resolution $HST$/STIS UV and high-S/N optical spectra of the moderately reddened B3-5~V star HD~62542. This remarkable sight line exhibits both very…
Aims. We present results of a comprehensive spectral study on the large-scale environment of AGNs based on Sloan Spectroscopic Survey data. Methods. We analyzed the spectra of galaxies in the environment of AGN and other activity classes up…
Active Galactic Nuclei (AGN) are intertwined with galaxy evolution, injecting energy into the interstellar medium (ISM) that could regulate star formation as a galaxy evolves. However, the phenomena through which we observe AGN are…
I present a generalized power-law diagnostic that allows to identify the presence of active galactic nuclei (AGN) in infrared (IR) galaxies at z>1, down to flux densities at which the extragalactic IR background is mostly resolved. I derive…
We present near-infrared and millimeter investigations of the nucleus of the infrared luminous galaxy NGC 4418, which previous observations suggest possesses a powerful buried AGN. We found the following main results: (1) The infrared…
We discuss the spectral analysis of a sample of 63 Active Galactic Nuclei (AGN) detected above a limiting flux of $S(8-24$ keV$)=7\times10^{-14}$ erg/s/cm$^2$ in the multi-tiered NuSTAR Extragalactic Survey program. The sources span a…
We observed Hubble V, the brightest HII region complex in the dwarf irregular galaxy NGC 6822, at near-infrared (1.8--2.4 um) wavelengths using the Cooled Grating Spectrometer 4 (CGS4) at the United Kingdom Infra-Red Telescope (UKIRT). The…
Our aim is to explore the nature of emission line galaxies by combining high-resolution observations obtained in different bands to understand which objects are powered by an Active Galactic Nucleus(AGN). From the spectroscopic Palomar…
We use quasi-simultaneous near-infrared (near-IR) and optical spectroscopy from four observing runs to study the continuum around 1 micron in 23 well-known broad-emission line active galactic nuclei (AGN). We show that, after correcting the…
Recent observations reveal galaxies in the early Universe (2<z<6.4) with large reservoirs of molecular gas and extreme star formation rates. For a very large range of sources, a tight relationship exists between star formation rate and the…
Integral-field spectroscopy of molecular hydrogen in the optical wavelength region and complementary long-slit near-infrared spectroscopy are presented towards HH91A.The detection of some 200 H_2 lines arising from ro-vibrational levels up…
We present observational evidences that dust in the circumnuclear region of AGNs has different properties than in the Galactic diffuse interstellar medium. By comparing the reddening of optical and infrared broad lines and the X-ray…
In order to characterize the amount of recent or ongoing stellar formation in the circumnuclear region of active galaxies on a statistically sound basis, we have studied the stellar component of the nuclear spectra in three different…
In the last decade of Active Galactic Nuclei (AGN) monitoring programs, the Mets\"ahovi Radio Observatory detected multiple times seven powerful flaring narrow-line Seyfert 1 (NLS1) galaxies at 37 GHz. Several hypotheses have been proposed,…
Active Galactic Nuclei (AGN) are axisymmetric systems to first order; their observed properties are likely strong functions of inclination with respect to our line of sight. However, except for a few special cases, the specific inclinations…
Spectral energy distributions (SEDs) of the central few tens of parsec region of some of the nearest, most well studied, active galactic nuclei (AGN) are presented. These genuine AGN-core SEDs, mostly from Seyfert galaxies, are…
We present NIR observations of a sample of mainly interacting ULIRGs, comprising H and K band spectra. Our main aims are to investigate the power source of these extremely luminous objects and the various excitation mechanisms of the strong…