Search Publications
The near-infrared radius-luminosity relationship for active galactic nuclei
Peterson, Bradley M.; Elvis, Martin; Karovska, Margarita +4 more
Black hole masses for samples of active galactic nuclei (AGNs) are currently estimated from single-epoch optical spectra. In particular, the size of the broad-line emitting region needed to compute the black hole mass is derived from the optical or ultraviolet continuum luminosity. Here we consider the relationship between the broad-line region si…
High-resolution spectroscopy of the blue compact dwarf galaxy Haro 15 - I. Internal kinematics
Morrell, Nidia; Díaz, Ángeles I.; Firpo, Verónica +2 more
Using echelle spectroscopy, obtained at Las Campanas Observatory, we present a detailed study of the internal kinematics of the nebular material in multiple knots of the blue compact dwarf galaxy Haro 15. A detailed analysis of the complex emission-line profiles shows the presence of an underlying broad component in almost all knots, and the brigh…
Hubble Space Telescope survey of the Perseus cluster - III. The effect of local environment on dwarf galaxies
Conselice, Christopher J.; Penny, Samantha J.; de Rijcke, Sven +3 more
We present the results of a Hubble Space Telescope (HST) study of dwarf galaxies in the outer regions of the nearby rich Perseus cluster, down to MV=-12, and compare these with the dwarf population in the cluster core from our previous HST imaging. In this paper, we examine how properties such as the colour-magnitude relation, structure…
The massive star clusters in the dwarf merger ESO 185-IG13: is the red excess ubiquitous in starbursts?
Östlin, G.; Hayes, M.; Adamo, A. +1 more
We have investigated the starburst properties of the luminous blue compact galaxy ESO 185-IG13. The galaxy has been imaged with the high-resolution cameras onboard the Hubble Space Telescope. From the ultraviolet (UV) to the infrared (IR), the data reveal a system shaped by hundreds of young star clusters, and fine structures, like a tidal stream …
Residual rotation of the Hipparcos/Tycho-2 system as determined from the data of the XPM catalogue
Bobylev, V. V.; Akhmetov, V. S.; Fedorov, P. N.
From a comparison of absolute proper motions of stars from the XPM catalogue with those of the same stars from the PPMXL, UCAC3, Tycho-2 and XC1 catalogues, the equatorial components of the rotation vector of these coordinate systems are determined with respect to the coordinate system specified by positions and proper motions of XPM. These parame…
Mercer 5: a probable new globular cluster in the Galactic bulge
Maccarone, T. J.; de Grijs, R.; Lucas, P. W. +6 more
We present a detailed study of a dust-obscured Galactic star cluster Mercer 5 ([MCM2005b] 5) in an extremely crowded field in the Milky Way. Near-infrared (near-IR) photometry from United Kingdom Infrared Digital Sky Surveys (UKIDSS) and the Son of ISAAC on the New Technology Telescope (SofI/NTT), combined with near-IR spectroscopy also from SofI,…
The hierarchical build-up of the Tully-Fisher relation
Thomas, Daniel; Maraston, Claudia; Silk, Joseph +4 more
We use the semi-analytic model GalICS to predict the Tully-Fisher relation in the B, I and K bands, and its evolution with redshift, up to z∼ 1. We refined the determination of the disc galaxies rotation velocity, with a dynamical recipe for the rotation curve, rather than a simple conversion from the total mass to maximum velocity. The new recipe…
Evidence for a circumnuclear and ionized absorber in the X-ray obscured broad-line radio galaxy 3C 445
Reeves, J. N.; Braito, V.; Gofford, J. +1 more
Here we present the results of a Suzaku observation of the broad-line radio galaxy 3C 445. We confirm the results obtained with the previous X-ray observations which unveiled the presence of several soft X-ray emission lines and an overall X-ray emission which strongly resembles a typical type 2 Seyfert galaxy despite of the optical classification…
The high-energy view of the broad-line radio galaxy 3C 111
Ballo, L.; Tombesi, F.; Reeves, J. N. +2 more
We present the analysis of Suzaku and XMM-Newton observations of the broad-line radio galaxy (BLRG) 3C 111. Its high-energy emission shows variability, a harder continuum with respect to the radio-quiet active galactic nucleus population, and weak reflection features. Suzaku found the source in a minimum flux level; a comparison with the XMM-Newto…
The most recent burst of star formation in the massive elliptical galaxy NGC 1052
Prieto, M. A.; Acosta-Pulido, J. A.; López-Sanjuan, C. +2 more
High spatial resolution near-infrared (NIR) images of the central 24 × 24 arcsec2 (∼2 × 2 kpc2) of the elliptical galaxy NGC 1052 reveal a total of 25 compact sources randomly distributed in the region. 15 of them exhibit Hα luminosities an order of magnitude above the estimate for an evolved population of extreme horizontal …