Search Publications
X-ray properties of BzK-selected galaxies in the deepest X-ray fields
Nandra, K.; Laird, E. S.; Rangel, C. +1 more
We investigate the X-ray properties of BzK-selected galaxies at z ∼ 2 using deep X-ray data in the Chandra Deep Field-South (CDFS) and Chandra Deep Field-North (CDFN). A subset of these BzK galaxies have been proposed as Compton-thick active galactic nucleus (AGN) candidates based on a high ratio of infrared (IR) to ultraviolet (UV) star formation…
Resolving the coronal line region of NGC 1068 with near-infrared integral field spectroscopy
Komossa, S.; McGregor, Peter J.; Rodríguez-Ardila, A. +1 more
We present adaptive optics-assisted J- and K-band integral field spectroscopy of the inner 300 × 300 pc of the Seyfert 2 galaxy NGC 1068. The data were obtained with the Gemini Near-infrared Integral-Field Spectrograph integral field unit spectrometer, which provided us with high-spatial and high-spectral resolution sampling. The wavelength range …
The lack of star formation gradients in galaxy groups up to z ∼ 1.6
Finoguenov, A.; Berta, S.; Magnelli, B. +28 more
In the local Universe, galaxy properties show a strong dependence on environment. In cluster cores, early-type galaxies dominate, whereas star-forming galaxies are more and more common in the outskirts. At higher redshifts and in somewhat less dense environments (e.g. galaxy groups), the situation is less clear. One open issue is that of whether a…
Long-term monitoring of PKS 0537-441 with Fermi-LAT and multiwavelength observations
Covino, S.; Pian, E.; Sbarufatti, B. +21 more
We report on multiwavelength observations of the blazar PKS 0537-441 (z = 0.896) obtained from microwaves through γ-rays by Submillimeter Array, Rapid Eye Mounting, Automatic Telescope for Optical Monitoring (ATOM), Swift and Fermi mostly during 2008 August-2010 April. Strong variability has been observed in γ-rays, with two major flaring episodes…
Active galactic nucleus torus models and the puzzling infrared spectrum of IRAS F10214+4724
Siebenmorgen, R.; Verma, A.; Efstathiou, A. +1 more
We present a revised model for the infrared emission of the hyperluminous infrared galaxy IRAS F10214+4724 which takes into account recent photometric data from Spitzer and Herschel that sample the peak of its spectral energy distribution. We first present and discuss a grid of smooth active galactic nucleus (AGN) torus models computed with the me…
GAMA/H-ATLAS: linking the properties of submm detected and undetected early-type galaxies - I. z ≤ 0.06 sample
Ivison, R. J.; Häußler, B.; Cooray, A. +34 more
We present two large, nearby (0.013 ≤ z ≤ 0.06) samples of early-type galaxies (ETGs): a visually classified sample of 220 ETGs, created using source-matched data from the Galaxy and Mass Assembly (GAMA) data base with far-infrared/submm detections from Herschel-Astrophysical Terahertz Large Area Survey (H-ATLAS); and a visually classified sample …
Mapping the differential reddening in globular clusters
Kepler, S. O.; Bonatto, C.; Campos, Fabíola
We build differential-reddening maps for 66 Galactic globular clusters (GCs) with archival Hubble Space Telescope WFC/ACS F606W and F814W photometry. Because of the different GC sizes (characterized by the half-light radius Rh) and distances to the Sun, the WFC/ACS field of view (200 arcsec × 200 arcsec) coverage (Robs) lies …
Jeans instability criterion modified by external tidal field.
Jog, C. J.
The well-known Jeans criterion describes the onset of instabilities in an infinite, homogeneous, self-gravitating medium supported by pressure. Most realistic astrophysical systems, however, are not isolated - instead they are under the influence of an external field such as the tidal field due to a neighbour. Here, we do a linear perturbation ana…
A variation of the fraction of stars that form in bound clusters within M83.
Bastian, N.; Adamo, A.; Silva-Villa, E.
Recent observations, as well as theoretical studies, have suggested that stellar cluster formation may depend on local and global environmental properties. In particular, the fraction of stars that form within long-lived bound clusters (Γ) may depend on environment, with indications that it may be higher in the more extreme environments of high st…
The K-band luminosity functions of super star clusters in luminous infrared galaxies, their slopes and the effects of blending
Kankare, E.; Väisänen, P.; Randriamanakoto, Z. +3 more
Super star clusters (SSCs) are typically found in interacting galaxies and trace an extreme form of star formation. We present a K-band study of SSC candidates in a sample of local luminous infrared galaxies (LIRGs) using two adaptive optics instruments: the Very Large Telescope's Nasmyth Adaptive Optics System-COude Near Infrared CAmera (NACO) an…